15
Hindawi Publishing Corporation ISRN Ecology Volume 2013, Article ID 890862, 14 pages http://dx.doi.org/10.1155/2013/890862 Research Article Species Diversity and Tree Regeneration Patterns in Tropical Forests of the Western Ghats, India R. Jayakumar 1 and K. K. N. Nair 2 1 Centre for Environmental Management of Degraded Ecosystems, School of Environmental Studies, University of Delhi, Delhi 110007, India 2 Department of Forest Botany, Kerala Forest Research Institute, rissur, Kerala 680653, India Correspondence should be addressed to R. Jayakumar; [email protected] Received 5 February 2013; Accepted 19 April 2013 Academic Editors: C. Jarnevich and T. Karels Copyright © 2013 R. Jayakumar and K. K. N. Nair. is is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Study Aim. To assess species diversity and tree regeneration patterns of different vegetation types of Western Ghats, India. Rarefaction was used to estimate species diversity of different vegetation types. One-way ANOVA was used to test for differences in tree density and basal area of different vegetation types. Sorenson index of similarity was used to calculate change in species composition between mature trees and regenerating individuals. Results showed that species diversity and regeneration pattern of trees differ in different vegetation types of the forest landscape. Species-area and species-individual accumulation curve (rarefaction) against equal-sized sampling area in different vegetation types showed that species heterogeneity was higher in vegetation types at mid elevations while their abundance was higher in vegetation types at higher elevations. All the vegetation types of the study area were heterogeneously distributed. Tree regeneration was higher in species rich vegetation type with no sign of human disturbances. Change in species composition across mature and regenerating phase was more frequent in disturbed forest as compared to undisturbed or less disturbed forests. New entry species occur in all the vegetation types. 1. Introduction Tropical regions of the world are frequently decked with luxuriant vegetation rich in species. e diversity of tree spec- ies is a fundamental component of total biodiversity in many ecosystems because trees are ecosystem engineers that pro- vide resources and habitats for almost all other forest organ- isms [1]. In tropical forests, the diversity of tree species varies by geography, habitat parameters, and levels of disturbance [2]. Trees form the major structural and functional basis of tropical forest ecosystems and can serve as robust indicators of changes and stressors at the landscape scale [3]. e spatial heterogeneity of diversity may be the result of some underly- ing pattern or process such as environmental heterogeneity, biotic control, and abiotic/biotic coupling process [4]. Spatial patterns of species richness have been used extensively to identify biodiversity “hotspots” [5]. e assumption is that managing areas of high species richness equate to improved conservation outcomes. erefore richness usually was a positive predictor of places of conservation value, if these are defined as places where species of interest are especially abundant. Understanding species diversity and distribution patterns is important for helping managers to evaluate the complexity and resources of these forests. Quantitative plant diversity inventories of Indian tropical forests are available from various forests of Western Ghats [2836]. Comparison of the species diversity of different veg- etation types is oſten difficult because of the dissimilarity of the available data. Primary forests of Asia, especially those of the Western and Eastern Ghats of India, are fast disappearing due to diverse anthropogenic impacts. e primary stands are oſten replaced by forests of secondary species; alternatively, forest landscapes are converted to completely different uses [37]. Earlier studies of tropical tree regeneration have focused mainly on seedlings, which are usually more abundant than other life stages [3840]. Parameters of seedling stands are crucial components of tree population dynamics [41]. As floristic and structural composition changes from one

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Hindawi Publishing CorporationISRN EcologyVolume 2013 Article ID 890862 14 pageshttpdxdoiorg1011552013890862

Research ArticleSpecies Diversity and Tree Regeneration Patterns inTropical Forests of the Western Ghats India

R Jayakumar1 and K K N Nair2

1 Centre for Environmental Management of Degraded Ecosystems School of Environmental Studies University of DelhiDelhi 110007 India

2Department of Forest Botany Kerala Forest Research Institute Thrissur Kerala 680653 India

Correspondence should be addressed to R Jayakumar jayakumarudaygmailcom

Received 5 February 2013 Accepted 19 April 2013

Academic Editors C Jarnevich and T Karels

Copyright copy 2013 R Jayakumar and K K N Nair This is an open access article distributed under the Creative CommonsAttribution License which permits unrestricted use distribution and reproduction in any medium provided the original work isproperly cited

Study Aim To assess species diversity and tree regeneration patterns of different vegetation types of Western Ghats IndiaRarefaction was used to estimate species diversity of different vegetation types One-way ANOVA was used to test for differencesin tree density and basal area of different vegetation types Sorenson index of similarity was used to calculate change in speciescomposition between mature trees and regenerating individuals Results showed that species diversity and regeneration patternof trees differ in different vegetation types of the forest landscape Species-area and species-individual accumulation curve(rarefaction) against equal-sized sampling area in different vegetation types showed that species heterogeneity was higher invegetation types at mid elevations while their abundance was higher in vegetation types at higher elevations All the vegetationtypes of the study area were heterogeneously distributed Tree regeneration was higher in species rich vegetation type with no signof human disturbances Change in species composition acrossmature and regenerating phase wasmore frequent in disturbed forestas compared to undisturbed or less disturbed forests New entry species occur in all the vegetation types

1 Introduction

Tropical regions of the world are frequently decked withluxuriant vegetation rich in speciesThe diversity of tree spec-ies is a fundamental component of total biodiversity in manyecosystems because trees are ecosystem engineers that pro-vide resources and habitats for almost all other forest organ-isms [1] In tropical forests the diversity of tree species variesby geography habitat parameters and levels of disturbance[2] Trees form the major structural and functional basis oftropical forest ecosystems and can serve as robust indicatorsof changes and stressors at the landscape scale [3]The spatialheterogeneity of diversity may be the result of some underly-ing pattern or process such as environmental heterogeneitybiotic control and abioticbiotic coupling process [4] Spatialpatterns of species richness have been used extensively toidentify biodiversity ldquohotspotsrdquo [5] The assumption is thatmanaging areas of high species richness equate to improvedconservation outcomes Therefore richness usually was a

positive predictor of places of conservation value if theseare defined as places where species of interest are especiallyabundant Understanding species diversity and distributionpatterns is important for helping managers to evaluate thecomplexity and resources of these forests

Quantitative plant diversity inventories of Indian tropicalforests are available from various forests of Western Ghats[28ndash36] Comparison of the species diversity of different veg-etation types is often difficult because of the dissimilarity ofthe available data Primary forests of Asia especially those oftheWestern and Eastern Ghats of India are fast disappearingdue to diverse anthropogenic impactsTheprimary stands areoften replaced by forests of secondary species alternativelyforest landscapes are converted to completely different uses[37] Earlier studies of tropical tree regeneration have focusedmainly on seedlings which are usually more abundant thanother life stages [38ndash40] Parameters of seedling standsare crucial components of tree population dynamics [41]As floristic and structural composition changes from one

2 ISRN Ecology

community to another there are concomitant changes in thecompetitive abilities of seedlings that depend on shiftingopportunities for regeneration [42] Recruitment growthand survival are influenced by a range of microclimatic andedaphic factors which vary among different tropical forestformations [43] Phillips [44] analyzed tree turnover in 67mature forest sites representing most of the major tropicalforest regions of the world across the sites tree turnoverhad significantly increased since the 1950s Increased treeturnover has positive impacts on atmospheric quality andbiodiversity [1]

The Indian subcontinent has one of the worldrsquos richestfloras withmore than 17000 species of flowering plants alone[45] The Western Ghats one of the biodiversity ldquohotspotsrdquoin which our study was performed form a mountainousregion in peninsular India that extends 1400 km2 from themouth of the Tapti River in the north to the environs ofKanyakumari in the south [46] With this background weevaluated the diversity and regeneration patterns of treespecies in a section of the Nilgiri Biosphere Reserve aimingto provide fundamental data for appropriate managementstrategies (mainly to propose the study area as ProtectedArea) that will improve the ecosystem Specifically we (i)aim to examine and compare tree species diversity (richnessabundance and basal area) in six different vegetation typesrepresentative of the study area (ii) to assess tree distributionpattern (using Raunkiaerrsquos frequency class) and also tree girthdistribution of different vegetation of the study area and (iii)to determine natural regeneration patterns and changes inspecies compositions across mature and regenerating phasesof trees and also assess occurrence of new entry species indifferent representative forest types of the landscape

2 Methods

21 Study Area The study was conducted in the New Ama-rambalam Reserve Forests (Figure 1) which is situated inthe Western Ghats of India (11∘141015840ndash11∘241015840N 76∘111015840ndash76∘331015840 E)These stands are part of the Nilgiri Biosphere Reserve withinthe State of Kerala The reserve covers an area of about265 km2 Following the forest type terminology of UNESCO[47] the natural vegetation types of the area were tropicalbroad-leaved drought deciduous forests (DECI) tropical low-land broad-leaved semideciduous seasonal forests (SEMI)tropical lowland broad-leaved seasonal evergreen forests(EVER) tropical broad-leaved evergreensubmontane forests(SUBM) tropical broad-leaved seasonal evergreenmontaneforests (MONT) and tropical broad-leaved drought decid-uous woodlands (WOOD) DECI occurred in foothills ofGhats with reduced rainfall whereas the other forest forma-tions occurred at higher elevations that received rain throughmost of the year DECI occurred in an altitudinal range of 40ndash400m above mean sea level Other vegetation types occurredat elevations of 400ndash2554m (Table 1) In addition to sixvegetation types another forest formation occurs on the topof the Ghats (altitudinal range of 1800ndash2554m) called shortgrass savannah that has practically no tree species excludedfrom the present study Temperature in the study area ranged

from 17 to 37∘C diurnal variation seldom exceeded 16∘CThearea received an average rainfall of about 2600mm reachingamaximumof 6000mmMost precipitation fell in the South-West monsoon season which extends from June through theend of September High altitudes in the Ghats had rainfallthrough most of the year The monsoon precipitation washighest on western southwestern and northwestern slopesThe climate was hot from March to May and humid duringthe rainy season

22 Disturbances and Threats to the Study Area Forests nearhuman habitations (DECI) are highly degraded by firewoodcollection and cattle grazing this has led to impoverishedplant diversity in the area Seasonal fire in WOOD dam-ages many ecosystem components including trees and theirseedlings Remaining four vegetation types are more or lessundisturbed Poaching and fishing are also common in thearea Fish are killed with copper sulphate and explosives(locally known as Thotta) with indiscriminate killing ofmany species of aquatic fauna and flora In the face of suchdangers the rich diverse and dynamic forest formations ofthe region which contain rare endangered and threatened(RET) tree species [48] require species- location- and issue-specific management strategies in addition to the overallprotection provided by the Nilgiri Biosphere Reserve

23 Vegetation Sampling and Species Diversity Analysis Inthe period 2000ndash2003 we used a stratified random design tosample vegetation [47]The trees in the vegetation types wereclassified into three growth phases mature trees (ge30 cmgirth at breast height [gbh]) saplings (ge 10 lt 30 cmgbh) andseedlings (lt10 cmgbh andgt20 cmhigh) Initially all standingtrees gt10 cm gbh were counted in 30m times 30m plots (ie900m2 or 009 hectare [ha]) laid randomly in each vegetationtypeWithin each plot ten random subplots of 2mtimes 2mwerealso deployed in these we collected data on tree seedlingsA total of 23 ha contained 259 sampling plots The number ofplots deployed in each vegetation typewas 45 (4 ha) except forWOOD where total area (34 plots) was sampled Altitudes ofplots weremeasuredwith a pocket altimeter accurate to 20mTree gbh values were measured at 13m above ground level

To assess species-area and species-individuals (abun-dance) relationship and also estimate average species accu-mulation rate of different vegetation types species-areacurves and species-individual rarefaction curves (individual-based rarefaction) were created randomly selected 30 plotsof 30m times 30m size Rarefaction was used to investigatethe richness of the community expected in a random sam-ple of individuals taken from a census or collection Theheterogeneity index namely Shannon index was measuredusing the formula 1198671015840 = sum [(119899

119894119873)log

119890(119899119894119873)] where 1198671015840

is Shannon diversity index 119899119894is number of individuals of

species ldquo119894rdquo in a community sample and 119873 is total numberof individuals of all species in the community sample [49]Vegetation data including density (number of individualshaminus1) richness (number of species) and basal area (m2 haminus1)were assembled To assess species distribution Raunkiaer

ISRN Ecology 3

India

Wes

tern

Gha

ts

Location of NilgiriBiosphere Reserve

Nilgiri Biosphere AreaState boundary

Karnataka

GundalpetPulpally

Gudalur

OotyNAM

NilamburSV

Kerala

TamilNadu

Location of New Amarambalam RFwithin the Nilgiri Biosphere Reserve

Rivers and rivuletsForest road

35998400

11∘

25998400

11∘

76∘30

99840076

∘40

9984007

0 45 9

6∘50

99840076

∘60

998400 E

EWN

S2554 m

(kilometers)

Tropical broad-leaved drought deciduous forests (DECI)Tropical lowland semideciduous seasonal forests (SEMI)Tropical lowland broad-leaved seasonal evergreen forests (EVER)Tropical broad-leaved submontane forests (SUBM)Tropical broad-leaved drought deciduous woodlands (WOOD)Tropical broad-leaved montane forests (MONT)

Figure 1 Location and area maps of New Amarambalam Reserve Forests and adjoining forests

[50] divided percent frequency into five classes A (0ndash20)B (21ndash40) C (41ndash60) D (61ndash80) and E (81ndash100) toassess distribution of species Frequency diagrams representthe homogeneity or heterogeneity of a community as floristicuniformity varies with the value for classes A and E Whenclasses A B and C are relatively frequent the stand isheterogeneous and the greater the frequency of class E thegreater the homogeneity To assess girth pattern ghb of trees(gt10 cm gbh) of all the vegetation types was measured andcategorized into different girth class interval of 50 cm

24 Regeneration The regeneration status of a tree speciesin a given forest type was considered ldquogoodrdquo when seedlingdensity gt sapling density gt adult tree density ldquofairrdquo whenseedling density gt sapling density le adult density ldquopoorrdquowhen the species survived in only the sapling stage but notin the seedling stage ldquononerdquo for species with no sapling orseedling stages but present as adult trees and ldquonewrdquo whenadults of a species were absent but sapling andor seedlingstage(s) were present [31]When a species frequency distribu-tion fits a ldquoreverse Jrdquo pattern (high number of individuals in

4 ISRN Ecology

Table 1 Dominant trees (first three) and their densities (trees haminus1) in three different growth phases of six vegetation types International(UNESCO) and regional (Champion and Seth 1968lowast) terminology of vegetation types used See ldquoregenerationrdquo in Section 2 for procedureused to distinguish dominant species

Vegetation types Dominant species Density of tree phasesUNESCO Champion and Seth (1968) Mature Saplings Seedlings

Tropical broad-leaveddrought deciduousforests(DECI)

Southern tropical moistdeciduous forests

Xylia xylocarpa 259 23 3166Terminalia paniculata 228 52 333Lagerstroemiamicrocarpa 156 12 mdash

Wrightia tinctoria 108 86 166Holarrhena pubescens mdash 25 4833Bridelia airy-shawii 03 02 4666Radermachera xylocarpa 13 1 3500

Tropical lowlandbroad-leavedsemideciduous seasonalforests(SEMI)

West coast tropicalsemievergreen forests

Pterygota alata 49 815 245Reinwardtiodendronanamalaiense 30 85 3845

Strombosia zeylanica 16 85 456Palaquium ellipticum 14 96 240Xylia xylocarpa 19 12 96Calophyllum polyanthum 36 55 453

Tropical lowlandbroad-leaved seasonalevergreen forests(EVER)

West coast tropical evergreenforests

Palaquium ellipticum 93 38 4136Agrostistachys borneensis 71 69 223Myristica beddomei 39 27 573Reinwardtiodendronanamalaiense 28 56 1636

Calophyllum polyanthum 4 15 1042

Tropical broad-leaveddrought deciduouswoodlands(WOOD)

Subtropical hill savannahs

Wendlandia thyrsiflora 17 36 356Phyllanthus emblica 32 mdash mdashGlochidion ellipticum 23 24 mdashGnidia glauca 238 18 160Macaranga peltata 159 4 mdashErythrina stricta 08 16 80

Tropical broad-leavedevergreensubmontaneforests (SUBM)

Southern subtropicalbroad-leaved hill forests

Myristica beddomei 88 05 765Palaquium ellipticum 55 15 298Litsea stocksii 32 35 456Litsea floribunda 4 5 371

Tropical broad-leavedevergreenmontaneforests(MONT)

Southern montane wettemperate forests

Turpinia cochinchinensis 116 46 1855Rhododendron arboreum 102 34 206Symplocos obtusa 64 33 386Rhodomyrtus tomentosa 26 44 234Syzygiumcalophyllifolium 77 20 868

Litsea floribunda 30 7 870lowastChampion H G and Seth S K 1968 A revised survey of the forest types of India Oxford UK and IBH Publications New Delhi India

the seedling stage and gradually declining numbers throughthe sapling small tree and mature tree phases) that specieswas recognized as the dominant in the whole stand In orderto measure number of species shared between mature andregenerating phases Sorenson index of similarity [49] wasused 119878 = 2 119888(119886 + 119887) where 119878 is Sorenson index of similarity

119888 is number of species shared between growth phases (heremature tree phase and regenerating phase ie saplings +seedlings) 119886 is total number of species in growth phase 119886and b is total number of species in growth phase b Speciesis considered as new recruit when there was no tree specieswith mature (adult) stage

ISRN Ecology 5

58

100 98

17

75

3241

9181

17

64

3133

83 78

9

65

27

71

127 122

28

92

43

0

20

40

60

80

100

120

140

DECI SEMI EVER WOOD SUBM MONT

Num

ber o

f spe

cies

Vegetation types

Mature treesSaplings

SeedlingsTotal species

Figure 2 Species richness (number of species) by tree growth phase in six vegetation types occurring in the Western Ghats Multiplecomparison LSD post hoc test showed richness of all the vegetation types was significantly different (119875 lt 001ndash005) See Table 1 for anexplanation of vegetation type abbreviations

25 Statistical Analysis One-way ANOVA was used to testdifferences of density (ge30 cm gbh) overall species rich-ness and basal area among vegetation types LSD post hoctests were used to detect significant pair wise differencesamong means of dependent variables One-way analysisof covariance (ANCOVA) was conducted to test of thecovariate (abundance) is that it evaluates the relationshipbetween the covariate (abundance) and the dependant vari-able (species richness) controlling for the factor (vegetationtypes) Pearson correlation coefficients were calculated todetect significant correlations among vegetation parametersespecially cumulative species richness and abundance of eachvegetation typeWe used the statistical package SPSS (Version16 www-01ibmcomsoftwareanalyticsspss) for all testsFor rarefaction we used statistical software Biodiversity Pro(httpwwwsmiacukpeter-lamontbiodiversity-pro)

3 Results

31 Species Diversity In the six vegetation types sampled inthe study area there were 257 tree species belonging to 62families and 147 genera of angiosperms Richness of treespecies (Figure 2) was highest in SEMI (127 spp) and lowestin theWOOD (28 spp) Species-area and species-individualsaccumulation curve (rarefaction curve) against equal-sizedsampling areas in different vegetation types showed a distinctdifference in the richness and abundance Rarefaction canbe used to examine the evenness of the distribution ofspecies in assemblages by comparing steepness of curvesSteeper rarefaction curves indicate high heterogeneity Onestriking results of rarefaction curves was that SEMI andEVER have the highest curves This means that speciesdiversity per equal-sized area was highest in these vegetationtypes but MONT has the most individuals per unit areaVegetation type at other extreme (low species richness) wasWOOD and MONT (Figure 3) The overall difference inspecies richness among six vegetation types was statisticallysignificant (119865

5179= 651 119875 lt 00001) Species richness

and corresponding abundance were significantly positivelycorrelated in all the vegetation types (DECI 119903 = 098 119875 lt00001) SEMI 119903 = 095 119875 lt 00001 EVER 119903 = 094 119875 lt00001 WOOD 119903 = 077 119875 lt 00001 SUBM 119903 = 095 119875 lt00001 MONT 119903 = 087 119875 lt 00001) A primary analysisevaluating the homogeneity-of-regression (slopes) assump-tion indicated that the relationship between the covariate(abundance) and the dependant variable (species richness)differs significantly as a function of the independent variable(vegetation types) (1198772 = 0152 ANCOVA 119865

6179= 1334

119875 lt 0001) A significant interaction between the covariateand the factor suggests that the differences on the dependentvariable among groups vary as a function of the covariateSince the result from the ANCOVA was significant it is notmeaningful to proceed further The highest Shannon indexvalue occurred in SEMI (367 for plants with gbh ge 30 cm)and lowest value reported in WOOD (Table 2)

Dominant tree species in mature and sapling stages weremore or less similar in most vegetation types but dominantspecies in the seedling stage varied considerably (Table 1)Overall stand density of mature trees (ge30 cm gbh) washighest in MONT (855 trees haminus1) and lowest in WOOD(39 trees haminus1) Densities of both tree saplings and seedlingswere highest in EVER (Figure 4) Among 25 tree speciesdominant across the different forest types 16 dominated inthe tree phase 15 in the sapling phase and 14 in the seedlingphase Among the different forest types therewere significantdifference in tree (ge30 cm gbh) density (119875 lt 00001 119865

5389=

269) and basal area (119875 lt 0007 1198655389= 33) Mean basal

area of trees was highest in EVER (48m2 haminus1) and lowest inWOOD (Table 2)

Raunkiaerrsquos frequency analyses revealed that most ofthe tree species were rare as in the case for other tropicalforests In all forest types 60ndash95 of tree species werein the lowest frequency class (Figure 5) Furthermore therewere few individuals in the 80ndash100 frequency class Inforest types other than DECI 58ndash70 of trees were in thesmallest girth category (gbh 50ndash100 cm) in DECI only 37

6 ISRN Ecology

DECISEMIEVER

WOODSUBMMONT

120

100

80

60

40

20

0

Spec

ies

0 05 1 15 2 25Area (ha)

(a)

0

20

40

60

80

100

120

140

0 200 400 600 800 1000 1200 1400 1600 1800

Spec

ies

Individuals

DECISEMIEVER

WOODSUBMMONT

(b)

Figure 3 Species accumulation and rarefaction curves of different vegetation types Curves were created random series of 30 plots of 009 ha(ie 27 ha for each vegetation type) (a) Species-area curves (sample-based rarefaction) and (b) species-individuals curve (individuals-basedrarefaction) Looking at the individual-based rarefaction curve all four vegetation types seem to be quite similar in species richness exceptMONT which is drastically lower although containing the highest number of individuals WOOD which contain too few individuals toproduce a comparable result The sample-based rarefaction on the other hand identifies SEMI and EVER as the two most species richcommunities differing from the rest Rarefaction curves for six vegetation types predict the rate of accumulation of species with increasingnumber of individuals (abundance) See Table 1 for an explanation of vegetation type abbreviations

Table 2 Vegetation parameters calculated for three tree phases in different vegetation types See Table 1 for explanation of vegetation typeabbreviations

Vegetation types(Altitude range)

Rainfall(mm)

Mean temperaturein the coldestmonth (∘C)

Phases oftrees

Basal area(m2ha)

Shannonindex

DECI(40ndash400m) 1000ndash1500 28

Mature treesSaplingsSeedlings

2332020mdash

279248262

SEMI(400ndash650m)

2500ndash3500 24 Mature treesSaplingsSeedlings

4566089mdash

367315311

EVER(650ndash1200m)

3500ndash5000 22 Mature treesSaplingsSeedlings

4800124mdash

334309349

WOOD(900ndash1400m)

3500ndash5000 25 Mature treesSaplingsSeedlings

06904mdash

221216156

SUBM(1200ndash1800m)

5000ndash6000 13 Mature treesSaplingsSeedlings

3651069mdash

326345351

MONT(1800ndash2450m)

5000ndash6000 9 Mature treesSaplingsSeedlings

3087145mdash

321319271

lowastMature trees (ge30 cm gbh) saplings (ge 10lt 30 cm gbh) and seedlings (lt10 cm gbh)

of trees were in the smallest girth class (Figure 6) In WOODvegetation which was fire affected and grass dominated 96of trees were in the smallest girth class

32 Regeneration Frequencies of regenerating species(saplings + seedlings) were maximal in undisturbed forestcompared to disturbed one (caused by fuel wood collection

and cattle grazing) In DECI of 71 taxa recorded only 26were present in all three growth phases 24 were presentin only one stage and only 10 species were regeneratingwell (seedling gt sapling gt tree) Nevertheless Lagerstroemiamicrocarpa one of the dominant species in DECI hadno seedlings indicative of poor regeneration potential(Tables 1 and 3 see Supplementary Material Appendix 1available online at httpdxdoiorg1011552013890862)

ISRN Ecology 7

Table 3 Distribution pattern of mature and regenerating phases of trees occur in different vegetation types Regenerating species and speciesshare in all phases of trees was lower in disturbed vegetation type such as DECI and WOOD as compared to other vegetation types Percentsimilarity in species composition (using Sorenson index of similarity) of mature trees and regenerating individuals (saplings + seedlings) indifferent vegetation types of the study area and new species recruited (trees devoid of adult stage) are also shown

Vegetationtypes

Tree species occur inlowastRegeneratingspecies ()

Similarity betweenmature trees andregenerating individuals

New entryspecies ()All phases () Mature phase

only ()Regeneratingphase only ()

DECI 26 (37) 21 (30) 12 (17) 50 (70) 69 12 (17)SEMI 53 (41) 11 (9) 27 (21) 116 (91) 82 24 (18)EVER 49 (40) 11 (9) 24 (20) 111 (91) 81 23 (18)WOOD 8 (29) 8 (29) 11 (39) 20 (71) 49 10 (35)SUBM 40 (43) 4 (4) 18 (20) 87 (95) 88 20 (21)MONT 20 (47) 6 (14) 11 (26) 37 (86) 76 10 (23)lowastA number of species occur in saplings andor seedlings and these species may or may not have mature tree stage of species has been given in brackets

132 36

8

485

39

390 85

5

65

250 393

77

215 39

22073 95

57

7717

795

6971 16

395

1

10

100

1000

10000

100000

DECI SEMI EVER WOOD SUBM MONT

Den

sity

Vegetation types

Mature treesSaplingsSeedlings

Figure 4 Densities (no haminus1 in log10scale) of mature trees (ge30 cm

gbh (girth at breast height)) saplings (ge 10 lt 30 cm gbh) and seedl-ings (lt10 cm gbh) in six vegetation types occurring in the WesternGhats LSD post hoc test clarified that density of disturbed forestlike DECI and WOOD was significantly different with undisturbedvegetation type except MONT

In vegetation types influenced by disturbance and firelike WOOD 29 of species were common in all growthphases and seedling richness was very low in these types ofvegetation (Supplementary Material Appendix 2)

In vegetation types at mid elevations namely EVERand SEMI 49ndash53 of species were present in all growthphases 25ndash30 of species occurred in only one phase(Supplementary Material Appendices 3 and 4) In forestsat higher elevations namelySUBM and MONT 43 and47 of species respectively were present in all growthphases In SUBM 25 species had poor regeneration potential(Supplementary Material Appendix 5) In MONT 20 specieswere present in all growth phases and 12 had no regenerationpotential (Table 3 Supplementary Material Appendix 6)

33 Change in Species Composition among Tree Phases Over-all species richness of mature trees was higher than richnessof saplings and seedlings in all vegetation types Among the

dominant species a few trees had exceptionally large num-bers of seedling and saplings Individual trees did notcontribute equally to the seedling population or to laterrecruitment in the sapling stage Density of regeneratingindividuals (saplings + seedlings) was highest in EVER andlowest in WOOD There was significant difference in thedensity of regenerating individuals (seedling + saplings)among different vegetation types (119865

5611= 132 119875 lt 0001)

Also there was significant difference in the density of matureand regenerating phase among all vegetation types exceptWOOD (DECI 119865

1130= 117 119875 lt 0001 SEMI 119865

1269= 37

119875 lt 005 EVER 1198651255= 73 119875 lt 0008 WOOD 119865

141= 34

119875 lt 0059 SUBM 1198651201= 101 119875 lt 0002 MONT 119865

188=

51 119875 lt 0026)The overall changes in species composition from mature

stage to regenerating stage (sapling + seedling phases) ofdifferent vegetation types 21 that is 79 similarity (usingSorenson index of similarity) between mature and regenerat-ing phase In disturbed WOOD and DECI the similarity inspecies composition between mature trees and regeneratingindividuals was 49 and 69 respectively In little-disturbedvegetation types species similarity between mature trees andregenerating phases was relatively high In all the forest typesnew entry species (tree species with no adult stages) werepresent Percent of new entry species was highest in fireaffected WOOD vegetation (Table 3)

4 Discussion

41 Species Diversity Theuse of species-individuals curves inaddition to species-area curves provides a clear insight intospecies diversity More sampling area is required for speciesrich vegetation type compared to species poor one and ingeneral the minimum area varies with number of speciesfrom one vegetation type to another [51] In our data species-rich communities like SEMI and EVER seem to have lessdominance than species-poor communities However lowerrarefaction curve in MONT suggests that abundance effectmay not be the sole reason for high richness The accumu-lation of new species with increasing sampling effort canbe visualized with a species accumulation curve Increasing

8 ISRN Ecology

0

20

40

60

80

100

Frequency classes

DECI

0ndash20 21ndash40 41ndash60 61ndash80 81ndash100

Spec

ies (

)

(a)

0

20

40

60

80

100SEMI

Frequency classes0ndash20 21ndash40 41ndash60 61ndash80 81ndash100

Spec

ies (

)

(b)

0

20

40

60

80

100

EVER

Frequency classes0ndash20 21ndash40 41ndash60 61ndash80 81ndash100

Spec

ies (

)

(c)

0

20

40

60

80

100

WOOD

Frequency classes0ndash20 21ndash40 41ndash60 61ndash80 81ndash100

Spec

ies (

)

(d)

0

20

40

60

80

100

SUBM

Frequency classes0ndash20 21ndash40 41ndash60 61ndash80 81ndash100

Mature treesSaplingsSeedlings

Spec

ies (

)

(e)

0

20

40

60

80

100

MONT

Mature treesSaplingsSeedlings

Frequency classes0ndash20 21ndash40 41ndash60 61ndash80 81ndash100

Spec

ies (

)

(f)

Figure 5 Percent frequencies of trees (ge30 cm gbh) in different vegetation types Most of the species were in the lowest frequency class inall vegetation types other than MONT indicating that a few species were widely distributed most were restricted in distribution This is atypical species-abundance distribution (normal distribution) and the tree species in all the vegetation type were heterogeneous distributionin Raunkiaerrsquos sense

the area sampled increases observed species richness bothbecause more individuals get included in the sample andbecause large areas are environmentally more heterogeneousthan small areas [52] The correlation between species rich-ness and abundance suggests that process affecting change ineither richness or abundance also affects species diversity

Species richness of DECI was reduced likely due to lowrainfall and anthropogenic disturbances such as firewoodcollection and cattle grazing In fire affected WOOD grasseswere the dominant life forms these were intermingled with afew fire tolerant light demanding trees High species richnessof trees in SEMI EVER and SUBM was probably relatedto high rainfall and optimal climatic conditions (Table 2)Low temperature and high wind velocity in the MONT may

negatively impact tree growth and reduce species richnessthere DECI standswere dominated bymembers of the familyFabaceae while Euphorbiaceae and Rubiaceae dominated inEVER at mid elevations High elevation SUBM and MONTwere dominated bymembers of the Lauraceae andMyrtaceaewhich have volatile oils in their tissues that resist freezingdamage in plant cells [53]

Compared to DECI tree species diversity was very highin other forest types at higher elevations other than in thefire-affected WOOD High species diversity of SEMI is dueits transitional nature that is this vegetation type is ecotonearea suitable for both deciduous and evergreen tree species sothere is an increase in the number of species Species diversityindices for saplings were lower than those for mature trees

ISRN Ecology 9

3721 19 10 6 3 2 1 1

020406080

100DECI

Tree

s (

)

Girth classes

10ndash5

0

101ndash

150

151ndash

200

201ndash

250

251ndash

300

301ndash

350

351ndash

400

51ndash1

00

gt400

(a)

020406080

10060

20 9 3 2 2 21 1

SEMI

Tree

s (

)

Girth classes

10ndash5

0

101ndash

150

151ndash

200

201ndash

250

251ndash

300

301ndash

350

351ndash

400

51ndash1

00

gt400

(b)

020406080

10065

19 9 3 2 2 21 1

EVER

Tree

s (

)

Girth classes

10ndash5

0

101ndash

150

151ndash

200

201ndash

250

251ndash

300

301ndash

350

351ndash

400

51ndash1

00

gt400

(c)

020406080

100 96

4 0 0 0 0 0 0 0

WOOD

Tree

s (

)

Girth classes

10ndash5

0

101ndash

150

151ndash

200

201ndash

250

251ndash

300

301ndash

350

351ndash

400

51ndash1

00

gt400

(d)

020406080

10058

20 12 4 2 1 1 1 1

SUBM

Girth classes

10ndash5

0

101ndash

150

151ndash

200

201ndash

250

251ndash

300

301ndash

350

351ndash

400

Tree

s (

)

51ndash1

00

gt400

(e)

020406080

10070

243 2 1 0 0 0 0

MONT

Tree

s (

)

Girth classes

10ndash5

0

101ndash

150

151ndash

200

201ndash

250

251ndash

300

301ndash

350

351ndash

400

51ndash1

00

gt400

(f)

Figure 6 Girth frequency distributions of trees in different vegetation types of the study area Girth-size was highest in SEMI and EVER Ahigh percentage of lower girth class trees in DECI results from reduced fuel wood extraction by people of nearby areas The reverse J-shapedgbh distribution of trees indicates evolving or expanding population

and seedlings in DECI is due to overharvesting of saplingsfor firewood The lowest species diversity value in WOODindicates low species richness and dominance of one or twospecies in the tree community In the present study Shannonindex values for tree species are similar to values for othertropical forests of the world (Table 4) However detailedcomparisons with other studies are inadvisable because oflarge differences in sample size standard girth parametersand environmental conditions

Density and frequency distributions of trees contributeto the structure of tropical forests Tree density in DECI wasmuch lower than that of other forest types perhaps due to lowrainfall and anthropogenic disturbances Density was least inthe fire-affected WOOD Sapling densities were elevated inSEMI and EVER Late secondary successional species werewell represented in the sapling population of EVER whichmay be indicative of recent natural disturbances in this foresttype that promoted regeneration of late secondary speciesMONT had high sapling density due to the stunted nature oftrees caused by very low temperature and high wind velocityprevalent there [54]

Densities of trees in the study area were similar toestimates from tropical forests within India and other tropicalregions (Table 4) In tropical forests outside India there ismuch variation in the densities of trees gt30 cm gbh (98ndash1930 trees haminus1) especially in Amazonian forests In theNeotropics maximum species richness of tree individualsgt10 cm gbh reaches 300 haminus1 [55] In South-East Asia thehighest richness is 225 haminus1 [56]

In the present studymost of the species were in frequencyclass 0ndash20 and fewest were in frequency class 80ndash100The frequency distribution of tree species suggested thatmostof them had low frequency as would be expected in typicalspecies-abundance distribution A plant species should beconsidered homogeneously distributed when the numbersof individuals are the same in all parts of a community[50] Hence tree species in all the vegetation types of thestudy area were heterogeneously distributed Girth classfrequency distributions of most species in vegetation typeswe studied fit ldquoreverse Jrdquo-shaped patterns with most trees insmaller girth classes and few old trees Vegetation types otherthan WOOD fit negative exponential patterns indicative of

10 ISRN Ecology

Table4Ve

getatio

nparameterso

fforestcom

mun

ities

inthetropics

ofIndiaa

ndotherc

ountrie

s

Foresttypes

Locatio

nPlot

size(ha)

Tree

girth

studied

(cm)

Tree

density

(noha)

Tree

basal

area

(m2 ha)

Shanno

nindex

References

Presentstudy

DEC

IWestern

Ghats(N

BR)

4ha

ge30

cm132

234

279

Present

study

SEMI

ldquo4ha

ge30

cm368

457

367

ldquo

EVER

ldquo4ha

ge30

cm485

480

334

ldquo

WOOD

ldquo3ha

ge30

cm39

069

221

ldquo

SUBM

ldquo4ha

ge30

cm390

365

326

ldquo

MONT

ldquo4ha

ge30

cm855

309

321

ldquo

India

Evergreenforests

Silent

valleyWestern

Ghat

mdashge315

620ndash

709

29ndash103

mdash[6]

Moistdecidu

ousforests

Pepp

araWGhats

mdashge30

590ndash

740

13ndash51

2ndash33

[7]

Moistdecidu

ousforests

Chim

mon

yWestern

Ghats

mdashge30

558

3719

ndash24

[8]

Semievergreen

forests

Pepp

araWestern

Ghats

mdashge30

670ndash

940

45ndash6

229

[7]

Semievergreen

forests

Chim

mon

yWestern

Ghats

mdashge30

728

4727ndash32

[8]

Scrubjung

leto

wetevergreenforests

Kalakk

adRF

Western

Ghats

02

gt20

320ndash

1260

18ndash107

mdash[9]

Evergreenforests

Karnataka

044

mdash44

6ndash1386

33ndash4

8mdash

[10]

Evergreenforests

Pepp

ara

mdashge30

860ndash

1370

7633

[7]

Evergreenforests

NelliampathiWestern

Ghats

mdashge30

mdash498

3ndash37

[11]

Dry

tropicalforests

Vind

hyar

egion

mdashgt30

294ndash

559

7ndash23

mdash[12]

Dry

evergreenforests

Puthup

etSacred

GroveC

orom

andel

coast

02

gt20

280

11mdash

[13]

Trop

icalwe

tevergreen

forests

Kalakk

ad-M

undanthu

raiT

iger

Reserve

Western

Ghats

050

gt30

315ndash418

54ndash8

4mdash

[14]

Trop

icalwe

tevergreen

forests

KodayarWestern

Ghats

050

gt30

352ndash117

328ndash81

mdash[15]

Subtropicalh

illforests

Pepp

araWestern

Ghats

mdashge30

1580ndash1930

27ndash34

27

[7]

Mon

tane

temperateforests

Mannavanshola

mdashge30

566

52399

[16]

ISRN Ecology 11

Table4Con

tinued

Foresttypes

Locatio

nPlot

size(ha)

Tree

girth

studied

(cm)

Tree

density

(noha)

Tree

basal

area

(m2 ha)

Shanno

nindex

References

Other

coun

tries

Trop

icalrain

forests

(you

ngforests

)Ba

rrow

ColoradoIsland

Panam

a5

gt18

84ndash171

26ndash

52

mdash[17]

Trop

icalrain

forests

(old

forests

)Ba

rrow

ColoradoIsland

Panam

a50

gt18

143ndash177

43ndash5

mdash[18]

Trop

icalrain

forests

Amazon

ia3

314

1420

28ndash6

8mdash

[19]

Equatoria

linsular

forests

Easte

rnCa

rolline

Island

Panam

a50

gt314

98ndash114

17mdash

[20]

Trop

icalrain

forests

Jung

kaRe

serveMalaysia

1191

104

23mdash

[21]

Trop

icalrain

forests

Gun

ungSilamM

alaysia

004

314

513ndash1596

23ndash4

6mdash

[22]

Trop

icalmoistforests

Sing

apore

04

gt63

604

mdashmdash

[23]

Trop

icalrain

forests

Valcan

BarvaCostaRica

6gt314

391ndash617

mdashmdash

[24]

Slop

eforests

New

Caledo

nia

28

gt314

1533

49mdash

[25]

Allu

vium

forests

New

Caledo

nia

26

gt314

1183

47mdash

[25]

Equatoria

lforests

KongoIsland

mdashmdash

440ndash

553

10ndash4

5mdash

[26]

Trop

icalrain

forests

Amazon

ia3

gt314

1720

78mdash

[19]

Trop

icalseason

alrain

forests

Xishuang

bann

aCh

ina

2500

m2

15154

mdash34

[27]

Trop

icalmon

tane

rain

forests

Xishuang

bann

aCh

ina

1600

m2

15123

mdash32

[27]

Evergreenbroadleaved

forests

Xishuang

bann

aCh

ina

1200

m2

15165

mdash25

[27]

Mon

soon

forests

Xishuang

bann

aCh

ina

400m

210

150

mdash16

[27]

ldquoStudy

cond

uctedin

6different

vegetatio

ntypeso

fWestern

Ghats(N

BR)

12 ISRN Ecology

relatively undisturbed or less disturbed conditions in thestands The high annual precipitation rate and optimumtemperature of EVER may have contributed to high treegrowth rate and higher tree basal area

42 Regeneration All other vegetation types had betterregeneration than DECI In WOOD the transition rate ofstems from small girth classes to larger girth classes was lowPoor tree regeneration in DECI and WOOD can probablybe attributed to fuel wood collection frequent fires andgrazing by cattle In all forest types 29ndash47 of tree specieswere present in all three growth phases other species werepresent in either one or two growth phases Dominant speciesoccurred in all girth classes of vegetation types other thanWOOD in whichmost trees were in the smaller girth classesThere were more large trees in vegetation types like SEMIand EVER and in these sapling and seedling densities wereadequate for restocking the complement of canopy trees

Change in species composition across mature and regen-erating tree phases was more frequent in disturbed foresttypes like DECI and WOOD In some cases the dominantspecies in adult and seedling stages were quite differentin these two disturbed forest types Our results are notcongruent with observationsmade in northeastern India [39]where tree seedling survival rate increases with increasingforest disturbance We found species without regeneratingphases these are unlikely to persist Others that occurred onlyin seedling and sapling stages were new entrants to the forestspecies complement These are examples of discontinuouspopulation structures Such structures occur in a number ofother tropical countries [57ndash59] The dominant species in aforest stand is generally present in all size classes [38] Thesize class structures of trees indicate the probability of speciespersistence into the future this information is very valuablein the design of management strategies aiming to improvestand structure and species diversity Changes in speciescomposition and recruitment of new species in differentvegetation types are indicative of future species compositionin changing environments

5 Conclusions

The species diversity of trees varied across vegetation types inthe Western Ghats landscape Rarefaction curves show thatspecies diversity is highest in SEMI and EVER and lowest inWOOD while species abundance is highest in MONT Vege-tation types of study area are in heterogeneous in distributionThere were large differences in species composition of adulttrees and regenerating individuals in the disturbed vegetationtypes as compared to undisturbed stands The present studyreveals that the anthropogenic disturbance causes disruptionof forest structure and change in species composition whichultimately leads to reduction of tree species richness andabundance which are the major attributes of forests Newrecruits were found in all vegetation types indicating thattheywere not headed to extinction however disturbed standsmay move to new species compositions in the future

Acknowledgments

The authors are thankful to the Ministry of Environmentand Forests for financial support and the Vice Chancellorof University of Delhi and the Director of Kerala ForestResearch Institute for facilities provided The first authorwould like to thank Professor C R Babu for facilities andencouragement The authors are very much obliged to allmembers of the Cholanaikkan tribe who helped duringthe field survey The Kerala Forest Department provided alllogistical support for the floristic and ecological survey of theforest area (trees haminus1) in three different growth phases of sixvegetation

References

[1] M A Huston Biological Diversity The Coexistence of Species inChanging Landscapes Cambridge University Press CambridgeUK 1994

[2] T C Whitmore An Introduction to Tropical Rain ForestsOxfordUniversity Press NewYork NYUSA 2nd edition 1998

[3] M L Khan S Menon and K S Bawa ldquoEffectiveness of theprotected area network in biodiversity conservation a case-study of Meghalaya staterdquo Biodiversity and Conservation vol 6no 6 pp 853ndash868 1997

[4] C M Pringle ldquoNutrient spatial heterogeneity effects on com-munity structure physiognomy and diversity of stream algaerdquoEcology vol 71 no 3 pp 905ndash920 1990

[5] M Parviainen M Marmion M Luoto W Thuiller and RK Heikkinen ldquoUsing summed individual species models andstate-of-the-art modelling techniques to identify threatenedplant species hotspotsrdquo Biological Conservation vol 142 no 11pp 2501ndash2509 2009

[6] J S Singh S P Singh A K Saxena and Y S Ravat ldquoThe forestvegetation of Silent Valleyrdquo in Tropical Rain Forests The LeedsSymposium pp 25ndash52 1984

[7] A O Varghese ldquoAssessment of biodiversity of PepparaWildlifeSanctuary Trivandrum District Keralardquo Journal of Economicand Taxonomic Botany vol 23 pp 117ndash127 1998

[8] M A Suraj Phytosociological and vagetation mapping at chim-mony wildlife Sanctuary (Kerala) using remote sensing technique[PhD thesis] FRI University Dehradun India 1997

[9] N Parthasarathy Studies on the vacular flora structure andnutrient cycling in Kalakad Reserve Forest Western Ghats TamilNadu [PhD thesis] University of Madras Tamil Nadu India1986

[10] S N Rai and J Proctor ldquoEcological studies on four rainforests in Karnataka India environment forest structure andvegetationrdquo Journal of Vegetation Science vol 1 pp 609ndash6141986

[11] U M Chadrashekara A R R Menon K K N Nair NSasidharan and K Swarupanandan ldquoEvaluating plant diversityin different forest types of Kerala by laying out permanent sam-ple plotsrdquo KFRI Research Report 156 Kerala Forest ResearchInstitute Peechi India 1998

[12] C S Jha and J S Singh ldquoComposition and dynamics of drytropical Forest in relation to soil texturerdquo Journal of VegetationScience vol 1 no 5 pp 609ndash614 1990

[13] NVisalakshi ldquoVegetation analysis of two tropical dry evergreenforests in southern IndiardquoTropical Ecology vol 36 no 1 pp 117ndash127 1995

ISRN Ecology 13

[14] T Ganesh R Ganesan M Soubadra Devy P Davidar and K SBawa ldquoAssessment of plant biodiversity at amid-elevation ever-green forest of Kalakad-Mundanthurai Tiger Reserve WesternGhats Indiardquo Current Science vol 71 no 5 pp 379ndash392 1996

[15] S M Sundarapandian and P S Swamy ldquoForest ecosystemstructure and composition along an altitudinal gradient in theWestern Ghats South Indiardquo Journal of Tropical Forest Sciencevol 12 no 1 pp 104ndash123 2000

[16] K Swarupanandan N Sasidharan K C Chacko and SChanduBasha ldquoFloristic and ecological studies on the Sholasof Idukki Districtrdquo in Shola Forests of Kerala Environmentand Biodiverstiy K K N Nair S K Khanduri and K Bala-subramaniayan Eds pp 259ndash286 Kerala Forest DeparmentThiruvanathapuram Kerala Forest Research Institute PeechiIndia 2001

[17] R W Thorington S Tannenbaum A Tarak and R RudranldquoDistribution of trees in Baro Colorado Islands a hectaresamplerdquo in The Ecology of a Tropical Forest-Seasonal Rhythmsand Long-term Changes E G Leigh Jr A S Rand and D MWindsor Eds Smithsonian Institute Press Washington DCUSA 1982

[18] S P Hubbell and R B Foster ldquoDiversity of canopy speciesin a neotropical forest and implications for conservationrdquo inTropical Rain Forest Ecology and Management S L Sutton TCWhitmore andA C Chadwick Eds Blackwell Oxford UK1983

[19] D G Campbell D C Daly G T Prance and U N MacielldquoQuantitative ecological inventory of terra firme and varzeatropical forest on the Rio Xingu Brazilian Amazonrdquo Brittoniavol 38 no 4 pp 369ndash393 1986

[20] S Itow ldquoSpecies diversity of equatorial insular forests on Ponapeand Kosrae Micronesiardquo Ecological Research vol 1 no 2 pp223ndash227 1986

[21] C C Ho D M Newbery and M E D Poore ldquoForestcomposition and inferred dynamics in Jengka Forest ReserveMalaysiardquo Journal of Tropical Ecology vol 3 no 1 pp 25ndash561987

[22] J Proctor Y F Lee A M Langley W R C Munro and TNelson ldquoEcological studies onGunung Silam a small ultrabasicmountain Sabah Malaysiardquo Journal of Ecology vol 74 pp 455ndash463 1988

[23] F R Swan Jr ldquoTree distribution patterns in the Bukittimahnature reserve Singaporerdquo Gardens Bulletin vol 41 pp 59ndash811988

[24] A Heaney and J Proctor ldquoPreliminary studies on foreststructure and floristics on Volcan Barva Costa Ricardquo Journalof Tropical Ecology vol 6 no 3 pp 307ndash320 1990

[25] T Jaffre and J M Veillon ldquoEtude floristique et structuralede deux forets denses humides sur roches ultrabasiques enNouvelle- Caledonierdquo Bulletin du Museum National drsquoHistoireNaturelle vol 12 pp 243ndash273 1990

[26] MMosango ldquoContribution ldquoA lrsquoetude botanic biogeo 1rdquo ecosys-tem Foret en region equatorial (Ile KongoloZaire)rdquo BelgiumJournal of Botany vol 124 pp 167ndash194 1991

[27] M Cao and J Zhang ldquoTree species diversity of tropical forestvegetation in Xishuangbanna SW Chinardquo Biodiversity andConservation vol 6 no 7 pp 995ndash1006 1997

[28] C S Jha L Goparaju A Tripathi B Gharai A S Raghubanshiand J S Singh ldquoForest fragmentation and its impact onspecies diversity an analysis using remote sensing and GISrdquoBiodiversity and Conservation vol 14 no 7 pp 1681ndash1698 2005

[29] P S Roy C B S Dutt and P K Joshi ldquoTropical forest resourceassessment and monitoringrdquo Tropical Ecology vol 43 no 1 pp21ndash37 2002

[30] R Sagar A S Raghubanshi and J S Singh ldquoAsymptoticmodelsof species-area curve for measuring diversity of dry tropicalforest tree speciesrdquo Current Science vol 84 no 12 pp 1555ndash1560 2003

[31] R Sukumar H S Dattaraja H S Suresh et al ldquoLong-termmonitoring of vegetation in a tropical deciduous forest inMudumalai southern Indiardquo Current Science vol 62 pp 608ndash616 1992

[32] UMChandrashekara and P S Ramakrishnan ldquoVegetation andgap dynamics of a tropical wet evergreen forest in the WesternGhats of Kerala Indiardquo Journal of Tropical Ecology vol 10 no3 pp 337ndash354 1994

[33] T Ganesh R Ganesan M Soubadra Devy P Davidar and K SBawa ldquoAssessment of plant biodiversity at amid-elevation ever-green forest of Kalakad-Mundanthurai Tiger Reserve WesternGhats Indiardquo Current Science vol 71 no 5 pp 379ndash392 1996

[34] J P Pascal and R Pelissier ldquoStructure and floristic compositionof a tropical evergreen forest in south-west Indiardquo Journal ofTropical Ecology vol 12 no 2 pp 191ndash210 1996

[35] N Ayyappan and N Parthasarathy ldquoBiodiversity inventory oftrees in a large-scale permanent plot of tropical evergreen forestat Varagalaiar Anamalais Western Ghats Indiardquo Biodiversityand Conservation vol 8 no 11 pp 1533ndash1554 1999

[36] A Kumar B G Marcot and A Saxena ldquoTree species diversityand distribution patterns in tropical forests of Garo HillsrdquoCurrent Science vol 91 no 10 pp 1370ndash1381 2006

[37] N Parthasarathy ldquoTree diversity and distribution in undis-turbed and human-impacted sites of tropical wet evergreenforest in southern Western Ghats Indiardquo Biodiversity andConservation vol 8 no 10 pp 1365ndash1381 1999

[38] M L Khan J P N Rai and R S Tripathi ldquoPopulation structureof some tree species in disturbed and protected subtropicalforests of north-east Indiardquo Acta Oecologica vol 8 no 3 pp247ndash255 1987

[39] R S Tripathi and M L Khan ldquoRegeneration pattern andpopulation structure of trees in subtropical forest of North EastIndiardquo in Tropical Ecosystem-Ecology and Management K PSingh and J S Singh Eds pp 431ndash441 Wiley Eastern LimitedNew Delhi India 1992

[40] A E Scholl and A H Taylor ldquoRegeneration patterns in old-growth red fir-western white pine forests in the northern SierraNevada Lake Tahoe USArdquo Forest Ecology and Managementvol 235 no 1ndash3 pp 143ndash154 2006

[41] D A Clark ldquoRegeneration of canopy trees in tropical wetforestsrdquo Trends in Ecology and Evolution vol 1 no 6 pp 150ndash154 1986

[42] P C J Barker and J B Kirkpatrick ldquoPhyllocladus aspleniifoliusvariability in the population structure the regeneration nicheand dispersion patterns in Tasmanian forestsrdquo Australian Jour-nal of Botany vol 42 no 2 pp 163ndash190 1994

[43] C K Augspurger ldquoSeedling survival of tropical tree speciesinteractions of dispersal distance light-gaps and pathogensrdquoEcology vol 65 no 6 pp 1705ndash1712 1984

[44] O L Phillips ldquoLong-term environmental change in tropicalforests increasing tree turnoverrdquo Environmental Conservationvol 23 no 3 pp 235ndash248 1996

[45] Ministry of Environment and Forests ldquoPlant discoveries 2011newgenera species andnew recordsrdquo Botanical Survey of IndiaMinistry of Environment and Forests New Delhi India 2012

14 ISRN Ecology

[46] ldquoWeblink 2007rdquo httpwwwbiodiversityhotspotsorgxphot-spotshotspots by region

[47] D Mueller-Dombois and H Ellenberg Aims and Methods ofPlant Ecology John Wiley amp Sons New York NY USA 1974

[48] K K N Nair and R Jayakumar ldquoPhytogeography endemismand affinities of the flora of NewAmarambalamReserve Forestsin theWesternGhats of Indiardquo Indian Journal of Forestry vol 31pp 85ndash94 2008

[49] A E Magurran Ecological Diversity and Its MeasurementCroom Helm Ltd London UK 1988

[50] C Raunkiaer The Life Forms of Plants and Statistical PlantGeography Clarendon Press Oxford UK 1934

[51] B Rice andMWestoby ldquoPlant species richness at the 01 hectarescale in Australian vegetation compared to other continentsrdquoVegetatio vol 52 no 3 pp 129ndash140 1983

[52] SM Scheiner ldquoSix types of species-area curvesrdquoGlobal Ecologyand Biogeography vol 12 no 6 pp 441ndash447 2003

[53] H G Jones Plants and Microclimate Cambridge UniversityPress Cambridge UK 1983

[54] N C Nair The Southern Western Ghats A Biodiversity Con-servation Plan Indian National Trust for Arts and CulturalHeritage New Delhi India 1991

[55] AHGentry ldquoChanges in plant community diversity and floris-tic composition on environmental and geographical gradientrdquoAnnals of the Missouri Botanical Garden vol 75 no 1 pp 1ndash341988

[56] T CWhitmore Tropical Rain Forests of the Far East ClarendonPress Oxford UK 1984

[57] N V L Brokaw ldquoGap-phase regeneration of three pioneer treespecies in a tropical forestrdquo Journal of Ecology vol 75 no 1 pp9ndash19 1987

[58] S Itow and D Mueller-Dombois ldquoPopulation structure stand-level dieback and recovery of Scalesia pedunculata forest in theGalapagos Islandsrdquo Ecological Research vol 3 no 3 pp 333ndash339 1988

[59] T CWhitmore ldquoA review of some aspects of tropical rainforestseedling ecology with suggestions for further enquiryrdquo inEcology of Tropical Forest Tree Seedlings M D Swaine Ed pp3ndash39 UNESCOParthenon Paris France 1996

Submit your manuscripts athttpwwwhindawicom

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EcosystemsJournal of

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Advances in

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Environmental Chemistry

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ScientificaHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

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The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014

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ClimatologyJournal of

Page 2: Research Article Species Diversity and Tree Regeneration ...downloads.hindawi.com/archive/2013/890862.pdf · Species Diversity and Tree Regeneration Patterns in Tropical Forests of

2 ISRN Ecology

community to another there are concomitant changes in thecompetitive abilities of seedlings that depend on shiftingopportunities for regeneration [42] Recruitment growthand survival are influenced by a range of microclimatic andedaphic factors which vary among different tropical forestformations [43] Phillips [44] analyzed tree turnover in 67mature forest sites representing most of the major tropicalforest regions of the world across the sites tree turnoverhad significantly increased since the 1950s Increased treeturnover has positive impacts on atmospheric quality andbiodiversity [1]

The Indian subcontinent has one of the worldrsquos richestfloras withmore than 17000 species of flowering plants alone[45] The Western Ghats one of the biodiversity ldquohotspotsrdquoin which our study was performed form a mountainousregion in peninsular India that extends 1400 km2 from themouth of the Tapti River in the north to the environs ofKanyakumari in the south [46] With this background weevaluated the diversity and regeneration patterns of treespecies in a section of the Nilgiri Biosphere Reserve aimingto provide fundamental data for appropriate managementstrategies (mainly to propose the study area as ProtectedArea) that will improve the ecosystem Specifically we (i)aim to examine and compare tree species diversity (richnessabundance and basal area) in six different vegetation typesrepresentative of the study area (ii) to assess tree distributionpattern (using Raunkiaerrsquos frequency class) and also tree girthdistribution of different vegetation of the study area and (iii)to determine natural regeneration patterns and changes inspecies compositions across mature and regenerating phasesof trees and also assess occurrence of new entry species indifferent representative forest types of the landscape

2 Methods

21 Study Area The study was conducted in the New Ama-rambalam Reserve Forests (Figure 1) which is situated inthe Western Ghats of India (11∘141015840ndash11∘241015840N 76∘111015840ndash76∘331015840 E)These stands are part of the Nilgiri Biosphere Reserve withinthe State of Kerala The reserve covers an area of about265 km2 Following the forest type terminology of UNESCO[47] the natural vegetation types of the area were tropicalbroad-leaved drought deciduous forests (DECI) tropical low-land broad-leaved semideciduous seasonal forests (SEMI)tropical lowland broad-leaved seasonal evergreen forests(EVER) tropical broad-leaved evergreensubmontane forests(SUBM) tropical broad-leaved seasonal evergreenmontaneforests (MONT) and tropical broad-leaved drought decid-uous woodlands (WOOD) DECI occurred in foothills ofGhats with reduced rainfall whereas the other forest forma-tions occurred at higher elevations that received rain throughmost of the year DECI occurred in an altitudinal range of 40ndash400m above mean sea level Other vegetation types occurredat elevations of 400ndash2554m (Table 1) In addition to sixvegetation types another forest formation occurs on the topof the Ghats (altitudinal range of 1800ndash2554m) called shortgrass savannah that has practically no tree species excludedfrom the present study Temperature in the study area ranged

from 17 to 37∘C diurnal variation seldom exceeded 16∘CThearea received an average rainfall of about 2600mm reachingamaximumof 6000mmMost precipitation fell in the South-West monsoon season which extends from June through theend of September High altitudes in the Ghats had rainfallthrough most of the year The monsoon precipitation washighest on western southwestern and northwestern slopesThe climate was hot from March to May and humid duringthe rainy season

22 Disturbances and Threats to the Study Area Forests nearhuman habitations (DECI) are highly degraded by firewoodcollection and cattle grazing this has led to impoverishedplant diversity in the area Seasonal fire in WOOD dam-ages many ecosystem components including trees and theirseedlings Remaining four vegetation types are more or lessundisturbed Poaching and fishing are also common in thearea Fish are killed with copper sulphate and explosives(locally known as Thotta) with indiscriminate killing ofmany species of aquatic fauna and flora In the face of suchdangers the rich diverse and dynamic forest formations ofthe region which contain rare endangered and threatened(RET) tree species [48] require species- location- and issue-specific management strategies in addition to the overallprotection provided by the Nilgiri Biosphere Reserve

23 Vegetation Sampling and Species Diversity Analysis Inthe period 2000ndash2003 we used a stratified random design tosample vegetation [47]The trees in the vegetation types wereclassified into three growth phases mature trees (ge30 cmgirth at breast height [gbh]) saplings (ge 10 lt 30 cmgbh) andseedlings (lt10 cmgbh andgt20 cmhigh) Initially all standingtrees gt10 cm gbh were counted in 30m times 30m plots (ie900m2 or 009 hectare [ha]) laid randomly in each vegetationtypeWithin each plot ten random subplots of 2mtimes 2mwerealso deployed in these we collected data on tree seedlingsA total of 23 ha contained 259 sampling plots The number ofplots deployed in each vegetation typewas 45 (4 ha) except forWOOD where total area (34 plots) was sampled Altitudes ofplots weremeasuredwith a pocket altimeter accurate to 20mTree gbh values were measured at 13m above ground level

To assess species-area and species-individuals (abun-dance) relationship and also estimate average species accu-mulation rate of different vegetation types species-areacurves and species-individual rarefaction curves (individual-based rarefaction) were created randomly selected 30 plotsof 30m times 30m size Rarefaction was used to investigatethe richness of the community expected in a random sam-ple of individuals taken from a census or collection Theheterogeneity index namely Shannon index was measuredusing the formula 1198671015840 = sum [(119899

119894119873)log

119890(119899119894119873)] where 1198671015840

is Shannon diversity index 119899119894is number of individuals of

species ldquo119894rdquo in a community sample and 119873 is total numberof individuals of all species in the community sample [49]Vegetation data including density (number of individualshaminus1) richness (number of species) and basal area (m2 haminus1)were assembled To assess species distribution Raunkiaer

ISRN Ecology 3

India

Wes

tern

Gha

ts

Location of NilgiriBiosphere Reserve

Nilgiri Biosphere AreaState boundary

Karnataka

GundalpetPulpally

Gudalur

OotyNAM

NilamburSV

Kerala

TamilNadu

Location of New Amarambalam RFwithin the Nilgiri Biosphere Reserve

Rivers and rivuletsForest road

35998400

11∘

25998400

11∘

76∘30

99840076

∘40

9984007

0 45 9

6∘50

99840076

∘60

998400 E

EWN

S2554 m

(kilometers)

Tropical broad-leaved drought deciduous forests (DECI)Tropical lowland semideciduous seasonal forests (SEMI)Tropical lowland broad-leaved seasonal evergreen forests (EVER)Tropical broad-leaved submontane forests (SUBM)Tropical broad-leaved drought deciduous woodlands (WOOD)Tropical broad-leaved montane forests (MONT)

Figure 1 Location and area maps of New Amarambalam Reserve Forests and adjoining forests

[50] divided percent frequency into five classes A (0ndash20)B (21ndash40) C (41ndash60) D (61ndash80) and E (81ndash100) toassess distribution of species Frequency diagrams representthe homogeneity or heterogeneity of a community as floristicuniformity varies with the value for classes A and E Whenclasses A B and C are relatively frequent the stand isheterogeneous and the greater the frequency of class E thegreater the homogeneity To assess girth pattern ghb of trees(gt10 cm gbh) of all the vegetation types was measured andcategorized into different girth class interval of 50 cm

24 Regeneration The regeneration status of a tree speciesin a given forest type was considered ldquogoodrdquo when seedlingdensity gt sapling density gt adult tree density ldquofairrdquo whenseedling density gt sapling density le adult density ldquopoorrdquowhen the species survived in only the sapling stage but notin the seedling stage ldquononerdquo for species with no sapling orseedling stages but present as adult trees and ldquonewrdquo whenadults of a species were absent but sapling andor seedlingstage(s) were present [31]When a species frequency distribu-tion fits a ldquoreverse Jrdquo pattern (high number of individuals in

4 ISRN Ecology

Table 1 Dominant trees (first three) and their densities (trees haminus1) in three different growth phases of six vegetation types International(UNESCO) and regional (Champion and Seth 1968lowast) terminology of vegetation types used See ldquoregenerationrdquo in Section 2 for procedureused to distinguish dominant species

Vegetation types Dominant species Density of tree phasesUNESCO Champion and Seth (1968) Mature Saplings Seedlings

Tropical broad-leaveddrought deciduousforests(DECI)

Southern tropical moistdeciduous forests

Xylia xylocarpa 259 23 3166Terminalia paniculata 228 52 333Lagerstroemiamicrocarpa 156 12 mdash

Wrightia tinctoria 108 86 166Holarrhena pubescens mdash 25 4833Bridelia airy-shawii 03 02 4666Radermachera xylocarpa 13 1 3500

Tropical lowlandbroad-leavedsemideciduous seasonalforests(SEMI)

West coast tropicalsemievergreen forests

Pterygota alata 49 815 245Reinwardtiodendronanamalaiense 30 85 3845

Strombosia zeylanica 16 85 456Palaquium ellipticum 14 96 240Xylia xylocarpa 19 12 96Calophyllum polyanthum 36 55 453

Tropical lowlandbroad-leaved seasonalevergreen forests(EVER)

West coast tropical evergreenforests

Palaquium ellipticum 93 38 4136Agrostistachys borneensis 71 69 223Myristica beddomei 39 27 573Reinwardtiodendronanamalaiense 28 56 1636

Calophyllum polyanthum 4 15 1042

Tropical broad-leaveddrought deciduouswoodlands(WOOD)

Subtropical hill savannahs

Wendlandia thyrsiflora 17 36 356Phyllanthus emblica 32 mdash mdashGlochidion ellipticum 23 24 mdashGnidia glauca 238 18 160Macaranga peltata 159 4 mdashErythrina stricta 08 16 80

Tropical broad-leavedevergreensubmontaneforests (SUBM)

Southern subtropicalbroad-leaved hill forests

Myristica beddomei 88 05 765Palaquium ellipticum 55 15 298Litsea stocksii 32 35 456Litsea floribunda 4 5 371

Tropical broad-leavedevergreenmontaneforests(MONT)

Southern montane wettemperate forests

Turpinia cochinchinensis 116 46 1855Rhododendron arboreum 102 34 206Symplocos obtusa 64 33 386Rhodomyrtus tomentosa 26 44 234Syzygiumcalophyllifolium 77 20 868

Litsea floribunda 30 7 870lowastChampion H G and Seth S K 1968 A revised survey of the forest types of India Oxford UK and IBH Publications New Delhi India

the seedling stage and gradually declining numbers throughthe sapling small tree and mature tree phases) that specieswas recognized as the dominant in the whole stand In orderto measure number of species shared between mature andregenerating phases Sorenson index of similarity [49] wasused 119878 = 2 119888(119886 + 119887) where 119878 is Sorenson index of similarity

119888 is number of species shared between growth phases (heremature tree phase and regenerating phase ie saplings +seedlings) 119886 is total number of species in growth phase 119886and b is total number of species in growth phase b Speciesis considered as new recruit when there was no tree specieswith mature (adult) stage

ISRN Ecology 5

58

100 98

17

75

3241

9181

17

64

3133

83 78

9

65

27

71

127 122

28

92

43

0

20

40

60

80

100

120

140

DECI SEMI EVER WOOD SUBM MONT

Num

ber o

f spe

cies

Vegetation types

Mature treesSaplings

SeedlingsTotal species

Figure 2 Species richness (number of species) by tree growth phase in six vegetation types occurring in the Western Ghats Multiplecomparison LSD post hoc test showed richness of all the vegetation types was significantly different (119875 lt 001ndash005) See Table 1 for anexplanation of vegetation type abbreviations

25 Statistical Analysis One-way ANOVA was used to testdifferences of density (ge30 cm gbh) overall species rich-ness and basal area among vegetation types LSD post hoctests were used to detect significant pair wise differencesamong means of dependent variables One-way analysisof covariance (ANCOVA) was conducted to test of thecovariate (abundance) is that it evaluates the relationshipbetween the covariate (abundance) and the dependant vari-able (species richness) controlling for the factor (vegetationtypes) Pearson correlation coefficients were calculated todetect significant correlations among vegetation parametersespecially cumulative species richness and abundance of eachvegetation typeWe used the statistical package SPSS (Version16 www-01ibmcomsoftwareanalyticsspss) for all testsFor rarefaction we used statistical software Biodiversity Pro(httpwwwsmiacukpeter-lamontbiodiversity-pro)

3 Results

31 Species Diversity In the six vegetation types sampled inthe study area there were 257 tree species belonging to 62families and 147 genera of angiosperms Richness of treespecies (Figure 2) was highest in SEMI (127 spp) and lowestin theWOOD (28 spp) Species-area and species-individualsaccumulation curve (rarefaction curve) against equal-sizedsampling areas in different vegetation types showed a distinctdifference in the richness and abundance Rarefaction canbe used to examine the evenness of the distribution ofspecies in assemblages by comparing steepness of curvesSteeper rarefaction curves indicate high heterogeneity Onestriking results of rarefaction curves was that SEMI andEVER have the highest curves This means that speciesdiversity per equal-sized area was highest in these vegetationtypes but MONT has the most individuals per unit areaVegetation type at other extreme (low species richness) wasWOOD and MONT (Figure 3) The overall difference inspecies richness among six vegetation types was statisticallysignificant (119865

5179= 651 119875 lt 00001) Species richness

and corresponding abundance were significantly positivelycorrelated in all the vegetation types (DECI 119903 = 098 119875 lt00001) SEMI 119903 = 095 119875 lt 00001 EVER 119903 = 094 119875 lt00001 WOOD 119903 = 077 119875 lt 00001 SUBM 119903 = 095 119875 lt00001 MONT 119903 = 087 119875 lt 00001) A primary analysisevaluating the homogeneity-of-regression (slopes) assump-tion indicated that the relationship between the covariate(abundance) and the dependant variable (species richness)differs significantly as a function of the independent variable(vegetation types) (1198772 = 0152 ANCOVA 119865

6179= 1334

119875 lt 0001) A significant interaction between the covariateand the factor suggests that the differences on the dependentvariable among groups vary as a function of the covariateSince the result from the ANCOVA was significant it is notmeaningful to proceed further The highest Shannon indexvalue occurred in SEMI (367 for plants with gbh ge 30 cm)and lowest value reported in WOOD (Table 2)

Dominant tree species in mature and sapling stages weremore or less similar in most vegetation types but dominantspecies in the seedling stage varied considerably (Table 1)Overall stand density of mature trees (ge30 cm gbh) washighest in MONT (855 trees haminus1) and lowest in WOOD(39 trees haminus1) Densities of both tree saplings and seedlingswere highest in EVER (Figure 4) Among 25 tree speciesdominant across the different forest types 16 dominated inthe tree phase 15 in the sapling phase and 14 in the seedlingphase Among the different forest types therewere significantdifference in tree (ge30 cm gbh) density (119875 lt 00001 119865

5389=

269) and basal area (119875 lt 0007 1198655389= 33) Mean basal

area of trees was highest in EVER (48m2 haminus1) and lowest inWOOD (Table 2)

Raunkiaerrsquos frequency analyses revealed that most ofthe tree species were rare as in the case for other tropicalforests In all forest types 60ndash95 of tree species werein the lowest frequency class (Figure 5) Furthermore therewere few individuals in the 80ndash100 frequency class Inforest types other than DECI 58ndash70 of trees were in thesmallest girth category (gbh 50ndash100 cm) in DECI only 37

6 ISRN Ecology

DECISEMIEVER

WOODSUBMMONT

120

100

80

60

40

20

0

Spec

ies

0 05 1 15 2 25Area (ha)

(a)

0

20

40

60

80

100

120

140

0 200 400 600 800 1000 1200 1400 1600 1800

Spec

ies

Individuals

DECISEMIEVER

WOODSUBMMONT

(b)

Figure 3 Species accumulation and rarefaction curves of different vegetation types Curves were created random series of 30 plots of 009 ha(ie 27 ha for each vegetation type) (a) Species-area curves (sample-based rarefaction) and (b) species-individuals curve (individuals-basedrarefaction) Looking at the individual-based rarefaction curve all four vegetation types seem to be quite similar in species richness exceptMONT which is drastically lower although containing the highest number of individuals WOOD which contain too few individuals toproduce a comparable result The sample-based rarefaction on the other hand identifies SEMI and EVER as the two most species richcommunities differing from the rest Rarefaction curves for six vegetation types predict the rate of accumulation of species with increasingnumber of individuals (abundance) See Table 1 for an explanation of vegetation type abbreviations

Table 2 Vegetation parameters calculated for three tree phases in different vegetation types See Table 1 for explanation of vegetation typeabbreviations

Vegetation types(Altitude range)

Rainfall(mm)

Mean temperaturein the coldestmonth (∘C)

Phases oftrees

Basal area(m2ha)

Shannonindex

DECI(40ndash400m) 1000ndash1500 28

Mature treesSaplingsSeedlings

2332020mdash

279248262

SEMI(400ndash650m)

2500ndash3500 24 Mature treesSaplingsSeedlings

4566089mdash

367315311

EVER(650ndash1200m)

3500ndash5000 22 Mature treesSaplingsSeedlings

4800124mdash

334309349

WOOD(900ndash1400m)

3500ndash5000 25 Mature treesSaplingsSeedlings

06904mdash

221216156

SUBM(1200ndash1800m)

5000ndash6000 13 Mature treesSaplingsSeedlings

3651069mdash

326345351

MONT(1800ndash2450m)

5000ndash6000 9 Mature treesSaplingsSeedlings

3087145mdash

321319271

lowastMature trees (ge30 cm gbh) saplings (ge 10lt 30 cm gbh) and seedlings (lt10 cm gbh)

of trees were in the smallest girth class (Figure 6) In WOODvegetation which was fire affected and grass dominated 96of trees were in the smallest girth class

32 Regeneration Frequencies of regenerating species(saplings + seedlings) were maximal in undisturbed forestcompared to disturbed one (caused by fuel wood collection

and cattle grazing) In DECI of 71 taxa recorded only 26were present in all three growth phases 24 were presentin only one stage and only 10 species were regeneratingwell (seedling gt sapling gt tree) Nevertheless Lagerstroemiamicrocarpa one of the dominant species in DECI hadno seedlings indicative of poor regeneration potential(Tables 1 and 3 see Supplementary Material Appendix 1available online at httpdxdoiorg1011552013890862)

ISRN Ecology 7

Table 3 Distribution pattern of mature and regenerating phases of trees occur in different vegetation types Regenerating species and speciesshare in all phases of trees was lower in disturbed vegetation type such as DECI and WOOD as compared to other vegetation types Percentsimilarity in species composition (using Sorenson index of similarity) of mature trees and regenerating individuals (saplings + seedlings) indifferent vegetation types of the study area and new species recruited (trees devoid of adult stage) are also shown

Vegetationtypes

Tree species occur inlowastRegeneratingspecies ()

Similarity betweenmature trees andregenerating individuals

New entryspecies ()All phases () Mature phase

only ()Regeneratingphase only ()

DECI 26 (37) 21 (30) 12 (17) 50 (70) 69 12 (17)SEMI 53 (41) 11 (9) 27 (21) 116 (91) 82 24 (18)EVER 49 (40) 11 (9) 24 (20) 111 (91) 81 23 (18)WOOD 8 (29) 8 (29) 11 (39) 20 (71) 49 10 (35)SUBM 40 (43) 4 (4) 18 (20) 87 (95) 88 20 (21)MONT 20 (47) 6 (14) 11 (26) 37 (86) 76 10 (23)lowastA number of species occur in saplings andor seedlings and these species may or may not have mature tree stage of species has been given in brackets

132 36

8

485

39

390 85

5

65

250 393

77

215 39

22073 95

57

7717

795

6971 16

395

1

10

100

1000

10000

100000

DECI SEMI EVER WOOD SUBM MONT

Den

sity

Vegetation types

Mature treesSaplingsSeedlings

Figure 4 Densities (no haminus1 in log10scale) of mature trees (ge30 cm

gbh (girth at breast height)) saplings (ge 10 lt 30 cm gbh) and seedl-ings (lt10 cm gbh) in six vegetation types occurring in the WesternGhats LSD post hoc test clarified that density of disturbed forestlike DECI and WOOD was significantly different with undisturbedvegetation type except MONT

In vegetation types influenced by disturbance and firelike WOOD 29 of species were common in all growthphases and seedling richness was very low in these types ofvegetation (Supplementary Material Appendix 2)

In vegetation types at mid elevations namely EVERand SEMI 49ndash53 of species were present in all growthphases 25ndash30 of species occurred in only one phase(Supplementary Material Appendices 3 and 4) In forestsat higher elevations namelySUBM and MONT 43 and47 of species respectively were present in all growthphases In SUBM 25 species had poor regeneration potential(Supplementary Material Appendix 5) In MONT 20 specieswere present in all growth phases and 12 had no regenerationpotential (Table 3 Supplementary Material Appendix 6)

33 Change in Species Composition among Tree Phases Over-all species richness of mature trees was higher than richnessof saplings and seedlings in all vegetation types Among the

dominant species a few trees had exceptionally large num-bers of seedling and saplings Individual trees did notcontribute equally to the seedling population or to laterrecruitment in the sapling stage Density of regeneratingindividuals (saplings + seedlings) was highest in EVER andlowest in WOOD There was significant difference in thedensity of regenerating individuals (seedling + saplings)among different vegetation types (119865

5611= 132 119875 lt 0001)

Also there was significant difference in the density of matureand regenerating phase among all vegetation types exceptWOOD (DECI 119865

1130= 117 119875 lt 0001 SEMI 119865

1269= 37

119875 lt 005 EVER 1198651255= 73 119875 lt 0008 WOOD 119865

141= 34

119875 lt 0059 SUBM 1198651201= 101 119875 lt 0002 MONT 119865

188=

51 119875 lt 0026)The overall changes in species composition from mature

stage to regenerating stage (sapling + seedling phases) ofdifferent vegetation types 21 that is 79 similarity (usingSorenson index of similarity) between mature and regenerat-ing phase In disturbed WOOD and DECI the similarity inspecies composition between mature trees and regeneratingindividuals was 49 and 69 respectively In little-disturbedvegetation types species similarity between mature trees andregenerating phases was relatively high In all the forest typesnew entry species (tree species with no adult stages) werepresent Percent of new entry species was highest in fireaffected WOOD vegetation (Table 3)

4 Discussion

41 Species Diversity Theuse of species-individuals curves inaddition to species-area curves provides a clear insight intospecies diversity More sampling area is required for speciesrich vegetation type compared to species poor one and ingeneral the minimum area varies with number of speciesfrom one vegetation type to another [51] In our data species-rich communities like SEMI and EVER seem to have lessdominance than species-poor communities However lowerrarefaction curve in MONT suggests that abundance effectmay not be the sole reason for high richness The accumu-lation of new species with increasing sampling effort canbe visualized with a species accumulation curve Increasing

8 ISRN Ecology

0

20

40

60

80

100

Frequency classes

DECI

0ndash20 21ndash40 41ndash60 61ndash80 81ndash100

Spec

ies (

)

(a)

0

20

40

60

80

100SEMI

Frequency classes0ndash20 21ndash40 41ndash60 61ndash80 81ndash100

Spec

ies (

)

(b)

0

20

40

60

80

100

EVER

Frequency classes0ndash20 21ndash40 41ndash60 61ndash80 81ndash100

Spec

ies (

)

(c)

0

20

40

60

80

100

WOOD

Frequency classes0ndash20 21ndash40 41ndash60 61ndash80 81ndash100

Spec

ies (

)

(d)

0

20

40

60

80

100

SUBM

Frequency classes0ndash20 21ndash40 41ndash60 61ndash80 81ndash100

Mature treesSaplingsSeedlings

Spec

ies (

)

(e)

0

20

40

60

80

100

MONT

Mature treesSaplingsSeedlings

Frequency classes0ndash20 21ndash40 41ndash60 61ndash80 81ndash100

Spec

ies (

)

(f)

Figure 5 Percent frequencies of trees (ge30 cm gbh) in different vegetation types Most of the species were in the lowest frequency class inall vegetation types other than MONT indicating that a few species were widely distributed most were restricted in distribution This is atypical species-abundance distribution (normal distribution) and the tree species in all the vegetation type were heterogeneous distributionin Raunkiaerrsquos sense

the area sampled increases observed species richness bothbecause more individuals get included in the sample andbecause large areas are environmentally more heterogeneousthan small areas [52] The correlation between species rich-ness and abundance suggests that process affecting change ineither richness or abundance also affects species diversity

Species richness of DECI was reduced likely due to lowrainfall and anthropogenic disturbances such as firewoodcollection and cattle grazing In fire affected WOOD grasseswere the dominant life forms these were intermingled with afew fire tolerant light demanding trees High species richnessof trees in SEMI EVER and SUBM was probably relatedto high rainfall and optimal climatic conditions (Table 2)Low temperature and high wind velocity in the MONT may

negatively impact tree growth and reduce species richnessthere DECI standswere dominated bymembers of the familyFabaceae while Euphorbiaceae and Rubiaceae dominated inEVER at mid elevations High elevation SUBM and MONTwere dominated bymembers of the Lauraceae andMyrtaceaewhich have volatile oils in their tissues that resist freezingdamage in plant cells [53]

Compared to DECI tree species diversity was very highin other forest types at higher elevations other than in thefire-affected WOOD High species diversity of SEMI is dueits transitional nature that is this vegetation type is ecotonearea suitable for both deciduous and evergreen tree species sothere is an increase in the number of species Species diversityindices for saplings were lower than those for mature trees

ISRN Ecology 9

3721 19 10 6 3 2 1 1

020406080

100DECI

Tree

s (

)

Girth classes

10ndash5

0

101ndash

150

151ndash

200

201ndash

250

251ndash

300

301ndash

350

351ndash

400

51ndash1

00

gt400

(a)

020406080

10060

20 9 3 2 2 21 1

SEMI

Tree

s (

)

Girth classes

10ndash5

0

101ndash

150

151ndash

200

201ndash

250

251ndash

300

301ndash

350

351ndash

400

51ndash1

00

gt400

(b)

020406080

10065

19 9 3 2 2 21 1

EVER

Tree

s (

)

Girth classes

10ndash5

0

101ndash

150

151ndash

200

201ndash

250

251ndash

300

301ndash

350

351ndash

400

51ndash1

00

gt400

(c)

020406080

100 96

4 0 0 0 0 0 0 0

WOOD

Tree

s (

)

Girth classes

10ndash5

0

101ndash

150

151ndash

200

201ndash

250

251ndash

300

301ndash

350

351ndash

400

51ndash1

00

gt400

(d)

020406080

10058

20 12 4 2 1 1 1 1

SUBM

Girth classes

10ndash5

0

101ndash

150

151ndash

200

201ndash

250

251ndash

300

301ndash

350

351ndash

400

Tree

s (

)

51ndash1

00

gt400

(e)

020406080

10070

243 2 1 0 0 0 0

MONT

Tree

s (

)

Girth classes

10ndash5

0

101ndash

150

151ndash

200

201ndash

250

251ndash

300

301ndash

350

351ndash

400

51ndash1

00

gt400

(f)

Figure 6 Girth frequency distributions of trees in different vegetation types of the study area Girth-size was highest in SEMI and EVER Ahigh percentage of lower girth class trees in DECI results from reduced fuel wood extraction by people of nearby areas The reverse J-shapedgbh distribution of trees indicates evolving or expanding population

and seedlings in DECI is due to overharvesting of saplingsfor firewood The lowest species diversity value in WOODindicates low species richness and dominance of one or twospecies in the tree community In the present study Shannonindex values for tree species are similar to values for othertropical forests of the world (Table 4) However detailedcomparisons with other studies are inadvisable because oflarge differences in sample size standard girth parametersand environmental conditions

Density and frequency distributions of trees contributeto the structure of tropical forests Tree density in DECI wasmuch lower than that of other forest types perhaps due to lowrainfall and anthropogenic disturbances Density was least inthe fire-affected WOOD Sapling densities were elevated inSEMI and EVER Late secondary successional species werewell represented in the sapling population of EVER whichmay be indicative of recent natural disturbances in this foresttype that promoted regeneration of late secondary speciesMONT had high sapling density due to the stunted nature oftrees caused by very low temperature and high wind velocityprevalent there [54]

Densities of trees in the study area were similar toestimates from tropical forests within India and other tropicalregions (Table 4) In tropical forests outside India there ismuch variation in the densities of trees gt30 cm gbh (98ndash1930 trees haminus1) especially in Amazonian forests In theNeotropics maximum species richness of tree individualsgt10 cm gbh reaches 300 haminus1 [55] In South-East Asia thehighest richness is 225 haminus1 [56]

In the present studymost of the species were in frequencyclass 0ndash20 and fewest were in frequency class 80ndash100The frequency distribution of tree species suggested thatmostof them had low frequency as would be expected in typicalspecies-abundance distribution A plant species should beconsidered homogeneously distributed when the numbersof individuals are the same in all parts of a community[50] Hence tree species in all the vegetation types of thestudy area were heterogeneously distributed Girth classfrequency distributions of most species in vegetation typeswe studied fit ldquoreverse Jrdquo-shaped patterns with most trees insmaller girth classes and few old trees Vegetation types otherthan WOOD fit negative exponential patterns indicative of

10 ISRN Ecology

Table4Ve

getatio

nparameterso

fforestcom

mun

ities

inthetropics

ofIndiaa

ndotherc

ountrie

s

Foresttypes

Locatio

nPlot

size(ha)

Tree

girth

studied

(cm)

Tree

density

(noha)

Tree

basal

area

(m2 ha)

Shanno

nindex

References

Presentstudy

DEC

IWestern

Ghats(N

BR)

4ha

ge30

cm132

234

279

Present

study

SEMI

ldquo4ha

ge30

cm368

457

367

ldquo

EVER

ldquo4ha

ge30

cm485

480

334

ldquo

WOOD

ldquo3ha

ge30

cm39

069

221

ldquo

SUBM

ldquo4ha

ge30

cm390

365

326

ldquo

MONT

ldquo4ha

ge30

cm855

309

321

ldquo

India

Evergreenforests

Silent

valleyWestern

Ghat

mdashge315

620ndash

709

29ndash103

mdash[6]

Moistdecidu

ousforests

Pepp

araWGhats

mdashge30

590ndash

740

13ndash51

2ndash33

[7]

Moistdecidu

ousforests

Chim

mon

yWestern

Ghats

mdashge30

558

3719

ndash24

[8]

Semievergreen

forests

Pepp

araWestern

Ghats

mdashge30

670ndash

940

45ndash6

229

[7]

Semievergreen

forests

Chim

mon

yWestern

Ghats

mdashge30

728

4727ndash32

[8]

Scrubjung

leto

wetevergreenforests

Kalakk

adRF

Western

Ghats

02

gt20

320ndash

1260

18ndash107

mdash[9]

Evergreenforests

Karnataka

044

mdash44

6ndash1386

33ndash4

8mdash

[10]

Evergreenforests

Pepp

ara

mdashge30

860ndash

1370

7633

[7]

Evergreenforests

NelliampathiWestern

Ghats

mdashge30

mdash498

3ndash37

[11]

Dry

tropicalforests

Vind

hyar

egion

mdashgt30

294ndash

559

7ndash23

mdash[12]

Dry

evergreenforests

Puthup

etSacred

GroveC

orom

andel

coast

02

gt20

280

11mdash

[13]

Trop

icalwe

tevergreen

forests

Kalakk

ad-M

undanthu

raiT

iger

Reserve

Western

Ghats

050

gt30

315ndash418

54ndash8

4mdash

[14]

Trop

icalwe

tevergreen

forests

KodayarWestern

Ghats

050

gt30

352ndash117

328ndash81

mdash[15]

Subtropicalh

illforests

Pepp

araWestern

Ghats

mdashge30

1580ndash1930

27ndash34

27

[7]

Mon

tane

temperateforests

Mannavanshola

mdashge30

566

52399

[16]

ISRN Ecology 11

Table4Con

tinued

Foresttypes

Locatio

nPlot

size(ha)

Tree

girth

studied

(cm)

Tree

density

(noha)

Tree

basal

area

(m2 ha)

Shanno

nindex

References

Other

coun

tries

Trop

icalrain

forests

(you

ngforests

)Ba

rrow

ColoradoIsland

Panam

a5

gt18

84ndash171

26ndash

52

mdash[17]

Trop

icalrain

forests

(old

forests

)Ba

rrow

ColoradoIsland

Panam

a50

gt18

143ndash177

43ndash5

mdash[18]

Trop

icalrain

forests

Amazon

ia3

314

1420

28ndash6

8mdash

[19]

Equatoria

linsular

forests

Easte

rnCa

rolline

Island

Panam

a50

gt314

98ndash114

17mdash

[20]

Trop

icalrain

forests

Jung

kaRe

serveMalaysia

1191

104

23mdash

[21]

Trop

icalrain

forests

Gun

ungSilamM

alaysia

004

314

513ndash1596

23ndash4

6mdash

[22]

Trop

icalmoistforests

Sing

apore

04

gt63

604

mdashmdash

[23]

Trop

icalrain

forests

Valcan

BarvaCostaRica

6gt314

391ndash617

mdashmdash

[24]

Slop

eforests

New

Caledo

nia

28

gt314

1533

49mdash

[25]

Allu

vium

forests

New

Caledo

nia

26

gt314

1183

47mdash

[25]

Equatoria

lforests

KongoIsland

mdashmdash

440ndash

553

10ndash4

5mdash

[26]

Trop

icalrain

forests

Amazon

ia3

gt314

1720

78mdash

[19]

Trop

icalseason

alrain

forests

Xishuang

bann

aCh

ina

2500

m2

15154

mdash34

[27]

Trop

icalmon

tane

rain

forests

Xishuang

bann

aCh

ina

1600

m2

15123

mdash32

[27]

Evergreenbroadleaved

forests

Xishuang

bann

aCh

ina

1200

m2

15165

mdash25

[27]

Mon

soon

forests

Xishuang

bann

aCh

ina

400m

210

150

mdash16

[27]

ldquoStudy

cond

uctedin

6different

vegetatio

ntypeso

fWestern

Ghats(N

BR)

12 ISRN Ecology

relatively undisturbed or less disturbed conditions in thestands The high annual precipitation rate and optimumtemperature of EVER may have contributed to high treegrowth rate and higher tree basal area

42 Regeneration All other vegetation types had betterregeneration than DECI In WOOD the transition rate ofstems from small girth classes to larger girth classes was lowPoor tree regeneration in DECI and WOOD can probablybe attributed to fuel wood collection frequent fires andgrazing by cattle In all forest types 29ndash47 of tree specieswere present in all three growth phases other species werepresent in either one or two growth phases Dominant speciesoccurred in all girth classes of vegetation types other thanWOOD in whichmost trees were in the smaller girth classesThere were more large trees in vegetation types like SEMIand EVER and in these sapling and seedling densities wereadequate for restocking the complement of canopy trees

Change in species composition across mature and regen-erating tree phases was more frequent in disturbed foresttypes like DECI and WOOD In some cases the dominantspecies in adult and seedling stages were quite differentin these two disturbed forest types Our results are notcongruent with observationsmade in northeastern India [39]where tree seedling survival rate increases with increasingforest disturbance We found species without regeneratingphases these are unlikely to persist Others that occurred onlyin seedling and sapling stages were new entrants to the forestspecies complement These are examples of discontinuouspopulation structures Such structures occur in a number ofother tropical countries [57ndash59] The dominant species in aforest stand is generally present in all size classes [38] Thesize class structures of trees indicate the probability of speciespersistence into the future this information is very valuablein the design of management strategies aiming to improvestand structure and species diversity Changes in speciescomposition and recruitment of new species in differentvegetation types are indicative of future species compositionin changing environments

5 Conclusions

The species diversity of trees varied across vegetation types inthe Western Ghats landscape Rarefaction curves show thatspecies diversity is highest in SEMI and EVER and lowest inWOOD while species abundance is highest in MONT Vege-tation types of study area are in heterogeneous in distributionThere were large differences in species composition of adulttrees and regenerating individuals in the disturbed vegetationtypes as compared to undisturbed stands The present studyreveals that the anthropogenic disturbance causes disruptionof forest structure and change in species composition whichultimately leads to reduction of tree species richness andabundance which are the major attributes of forests Newrecruits were found in all vegetation types indicating thattheywere not headed to extinction however disturbed standsmay move to new species compositions in the future

Acknowledgments

The authors are thankful to the Ministry of Environmentand Forests for financial support and the Vice Chancellorof University of Delhi and the Director of Kerala ForestResearch Institute for facilities provided The first authorwould like to thank Professor C R Babu for facilities andencouragement The authors are very much obliged to allmembers of the Cholanaikkan tribe who helped duringthe field survey The Kerala Forest Department provided alllogistical support for the floristic and ecological survey of theforest area (trees haminus1) in three different growth phases of sixvegetation

References

[1] M A Huston Biological Diversity The Coexistence of Species inChanging Landscapes Cambridge University Press CambridgeUK 1994

[2] T C Whitmore An Introduction to Tropical Rain ForestsOxfordUniversity Press NewYork NYUSA 2nd edition 1998

[3] M L Khan S Menon and K S Bawa ldquoEffectiveness of theprotected area network in biodiversity conservation a case-study of Meghalaya staterdquo Biodiversity and Conservation vol 6no 6 pp 853ndash868 1997

[4] C M Pringle ldquoNutrient spatial heterogeneity effects on com-munity structure physiognomy and diversity of stream algaerdquoEcology vol 71 no 3 pp 905ndash920 1990

[5] M Parviainen M Marmion M Luoto W Thuiller and RK Heikkinen ldquoUsing summed individual species models andstate-of-the-art modelling techniques to identify threatenedplant species hotspotsrdquo Biological Conservation vol 142 no 11pp 2501ndash2509 2009

[6] J S Singh S P Singh A K Saxena and Y S Ravat ldquoThe forestvegetation of Silent Valleyrdquo in Tropical Rain Forests The LeedsSymposium pp 25ndash52 1984

[7] A O Varghese ldquoAssessment of biodiversity of PepparaWildlifeSanctuary Trivandrum District Keralardquo Journal of Economicand Taxonomic Botany vol 23 pp 117ndash127 1998

[8] M A Suraj Phytosociological and vagetation mapping at chim-mony wildlife Sanctuary (Kerala) using remote sensing technique[PhD thesis] FRI University Dehradun India 1997

[9] N Parthasarathy Studies on the vacular flora structure andnutrient cycling in Kalakad Reserve Forest Western Ghats TamilNadu [PhD thesis] University of Madras Tamil Nadu India1986

[10] S N Rai and J Proctor ldquoEcological studies on four rainforests in Karnataka India environment forest structure andvegetationrdquo Journal of Vegetation Science vol 1 pp 609ndash6141986

[11] U M Chadrashekara A R R Menon K K N Nair NSasidharan and K Swarupanandan ldquoEvaluating plant diversityin different forest types of Kerala by laying out permanent sam-ple plotsrdquo KFRI Research Report 156 Kerala Forest ResearchInstitute Peechi India 1998

[12] C S Jha and J S Singh ldquoComposition and dynamics of drytropical Forest in relation to soil texturerdquo Journal of VegetationScience vol 1 no 5 pp 609ndash614 1990

[13] NVisalakshi ldquoVegetation analysis of two tropical dry evergreenforests in southern IndiardquoTropical Ecology vol 36 no 1 pp 117ndash127 1995

ISRN Ecology 13

[14] T Ganesh R Ganesan M Soubadra Devy P Davidar and K SBawa ldquoAssessment of plant biodiversity at amid-elevation ever-green forest of Kalakad-Mundanthurai Tiger Reserve WesternGhats Indiardquo Current Science vol 71 no 5 pp 379ndash392 1996

[15] S M Sundarapandian and P S Swamy ldquoForest ecosystemstructure and composition along an altitudinal gradient in theWestern Ghats South Indiardquo Journal of Tropical Forest Sciencevol 12 no 1 pp 104ndash123 2000

[16] K Swarupanandan N Sasidharan K C Chacko and SChanduBasha ldquoFloristic and ecological studies on the Sholasof Idukki Districtrdquo in Shola Forests of Kerala Environmentand Biodiverstiy K K N Nair S K Khanduri and K Bala-subramaniayan Eds pp 259ndash286 Kerala Forest DeparmentThiruvanathapuram Kerala Forest Research Institute PeechiIndia 2001

[17] R W Thorington S Tannenbaum A Tarak and R RudranldquoDistribution of trees in Baro Colorado Islands a hectaresamplerdquo in The Ecology of a Tropical Forest-Seasonal Rhythmsand Long-term Changes E G Leigh Jr A S Rand and D MWindsor Eds Smithsonian Institute Press Washington DCUSA 1982

[18] S P Hubbell and R B Foster ldquoDiversity of canopy speciesin a neotropical forest and implications for conservationrdquo inTropical Rain Forest Ecology and Management S L Sutton TCWhitmore andA C Chadwick Eds Blackwell Oxford UK1983

[19] D G Campbell D C Daly G T Prance and U N MacielldquoQuantitative ecological inventory of terra firme and varzeatropical forest on the Rio Xingu Brazilian Amazonrdquo Brittoniavol 38 no 4 pp 369ndash393 1986

[20] S Itow ldquoSpecies diversity of equatorial insular forests on Ponapeand Kosrae Micronesiardquo Ecological Research vol 1 no 2 pp223ndash227 1986

[21] C C Ho D M Newbery and M E D Poore ldquoForestcomposition and inferred dynamics in Jengka Forest ReserveMalaysiardquo Journal of Tropical Ecology vol 3 no 1 pp 25ndash561987

[22] J Proctor Y F Lee A M Langley W R C Munro and TNelson ldquoEcological studies onGunung Silam a small ultrabasicmountain Sabah Malaysiardquo Journal of Ecology vol 74 pp 455ndash463 1988

[23] F R Swan Jr ldquoTree distribution patterns in the Bukittimahnature reserve Singaporerdquo Gardens Bulletin vol 41 pp 59ndash811988

[24] A Heaney and J Proctor ldquoPreliminary studies on foreststructure and floristics on Volcan Barva Costa Ricardquo Journalof Tropical Ecology vol 6 no 3 pp 307ndash320 1990

[25] T Jaffre and J M Veillon ldquoEtude floristique et structuralede deux forets denses humides sur roches ultrabasiques enNouvelle- Caledonierdquo Bulletin du Museum National drsquoHistoireNaturelle vol 12 pp 243ndash273 1990

[26] MMosango ldquoContribution ldquoA lrsquoetude botanic biogeo 1rdquo ecosys-tem Foret en region equatorial (Ile KongoloZaire)rdquo BelgiumJournal of Botany vol 124 pp 167ndash194 1991

[27] M Cao and J Zhang ldquoTree species diversity of tropical forestvegetation in Xishuangbanna SW Chinardquo Biodiversity andConservation vol 6 no 7 pp 995ndash1006 1997

[28] C S Jha L Goparaju A Tripathi B Gharai A S Raghubanshiand J S Singh ldquoForest fragmentation and its impact onspecies diversity an analysis using remote sensing and GISrdquoBiodiversity and Conservation vol 14 no 7 pp 1681ndash1698 2005

[29] P S Roy C B S Dutt and P K Joshi ldquoTropical forest resourceassessment and monitoringrdquo Tropical Ecology vol 43 no 1 pp21ndash37 2002

[30] R Sagar A S Raghubanshi and J S Singh ldquoAsymptoticmodelsof species-area curve for measuring diversity of dry tropicalforest tree speciesrdquo Current Science vol 84 no 12 pp 1555ndash1560 2003

[31] R Sukumar H S Dattaraja H S Suresh et al ldquoLong-termmonitoring of vegetation in a tropical deciduous forest inMudumalai southern Indiardquo Current Science vol 62 pp 608ndash616 1992

[32] UMChandrashekara and P S Ramakrishnan ldquoVegetation andgap dynamics of a tropical wet evergreen forest in the WesternGhats of Kerala Indiardquo Journal of Tropical Ecology vol 10 no3 pp 337ndash354 1994

[33] T Ganesh R Ganesan M Soubadra Devy P Davidar and K SBawa ldquoAssessment of plant biodiversity at amid-elevation ever-green forest of Kalakad-Mundanthurai Tiger Reserve WesternGhats Indiardquo Current Science vol 71 no 5 pp 379ndash392 1996

[34] J P Pascal and R Pelissier ldquoStructure and floristic compositionof a tropical evergreen forest in south-west Indiardquo Journal ofTropical Ecology vol 12 no 2 pp 191ndash210 1996

[35] N Ayyappan and N Parthasarathy ldquoBiodiversity inventory oftrees in a large-scale permanent plot of tropical evergreen forestat Varagalaiar Anamalais Western Ghats Indiardquo Biodiversityand Conservation vol 8 no 11 pp 1533ndash1554 1999

[36] A Kumar B G Marcot and A Saxena ldquoTree species diversityand distribution patterns in tropical forests of Garo HillsrdquoCurrent Science vol 91 no 10 pp 1370ndash1381 2006

[37] N Parthasarathy ldquoTree diversity and distribution in undis-turbed and human-impacted sites of tropical wet evergreenforest in southern Western Ghats Indiardquo Biodiversity andConservation vol 8 no 10 pp 1365ndash1381 1999

[38] M L Khan J P N Rai and R S Tripathi ldquoPopulation structureof some tree species in disturbed and protected subtropicalforests of north-east Indiardquo Acta Oecologica vol 8 no 3 pp247ndash255 1987

[39] R S Tripathi and M L Khan ldquoRegeneration pattern andpopulation structure of trees in subtropical forest of North EastIndiardquo in Tropical Ecosystem-Ecology and Management K PSingh and J S Singh Eds pp 431ndash441 Wiley Eastern LimitedNew Delhi India 1992

[40] A E Scholl and A H Taylor ldquoRegeneration patterns in old-growth red fir-western white pine forests in the northern SierraNevada Lake Tahoe USArdquo Forest Ecology and Managementvol 235 no 1ndash3 pp 143ndash154 2006

[41] D A Clark ldquoRegeneration of canopy trees in tropical wetforestsrdquo Trends in Ecology and Evolution vol 1 no 6 pp 150ndash154 1986

[42] P C J Barker and J B Kirkpatrick ldquoPhyllocladus aspleniifoliusvariability in the population structure the regeneration nicheand dispersion patterns in Tasmanian forestsrdquo Australian Jour-nal of Botany vol 42 no 2 pp 163ndash190 1994

[43] C K Augspurger ldquoSeedling survival of tropical tree speciesinteractions of dispersal distance light-gaps and pathogensrdquoEcology vol 65 no 6 pp 1705ndash1712 1984

[44] O L Phillips ldquoLong-term environmental change in tropicalforests increasing tree turnoverrdquo Environmental Conservationvol 23 no 3 pp 235ndash248 1996

[45] Ministry of Environment and Forests ldquoPlant discoveries 2011newgenera species andnew recordsrdquo Botanical Survey of IndiaMinistry of Environment and Forests New Delhi India 2012

14 ISRN Ecology

[46] ldquoWeblink 2007rdquo httpwwwbiodiversityhotspotsorgxphot-spotshotspots by region

[47] D Mueller-Dombois and H Ellenberg Aims and Methods ofPlant Ecology John Wiley amp Sons New York NY USA 1974

[48] K K N Nair and R Jayakumar ldquoPhytogeography endemismand affinities of the flora of NewAmarambalamReserve Forestsin theWesternGhats of Indiardquo Indian Journal of Forestry vol 31pp 85ndash94 2008

[49] A E Magurran Ecological Diversity and Its MeasurementCroom Helm Ltd London UK 1988

[50] C Raunkiaer The Life Forms of Plants and Statistical PlantGeography Clarendon Press Oxford UK 1934

[51] B Rice andMWestoby ldquoPlant species richness at the 01 hectarescale in Australian vegetation compared to other continentsrdquoVegetatio vol 52 no 3 pp 129ndash140 1983

[52] SM Scheiner ldquoSix types of species-area curvesrdquoGlobal Ecologyand Biogeography vol 12 no 6 pp 441ndash447 2003

[53] H G Jones Plants and Microclimate Cambridge UniversityPress Cambridge UK 1983

[54] N C Nair The Southern Western Ghats A Biodiversity Con-servation Plan Indian National Trust for Arts and CulturalHeritage New Delhi India 1991

[55] AHGentry ldquoChanges in plant community diversity and floris-tic composition on environmental and geographical gradientrdquoAnnals of the Missouri Botanical Garden vol 75 no 1 pp 1ndash341988

[56] T CWhitmore Tropical Rain Forests of the Far East ClarendonPress Oxford UK 1984

[57] N V L Brokaw ldquoGap-phase regeneration of three pioneer treespecies in a tropical forestrdquo Journal of Ecology vol 75 no 1 pp9ndash19 1987

[58] S Itow and D Mueller-Dombois ldquoPopulation structure stand-level dieback and recovery of Scalesia pedunculata forest in theGalapagos Islandsrdquo Ecological Research vol 3 no 3 pp 333ndash339 1988

[59] T CWhitmore ldquoA review of some aspects of tropical rainforestseedling ecology with suggestions for further enquiryrdquo inEcology of Tropical Forest Tree Seedlings M D Swaine Ed pp3ndash39 UNESCOParthenon Paris France 1996

Submit your manuscripts athttpwwwhindawicom

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EcosystemsJournal of

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MeteorologyAdvances in

EcologyInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Marine BiologyJournal of

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Hindawi Publishing Corporationhttpwwwhindawicom

Applied ampEnvironmentalSoil Science

Volume 2014

Advances in

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Environmental Chemistry

Atmospheric SciencesInternational Journal of

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Waste ManagementJournal of

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International Journal of

Geophysics

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

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EarthquakesJournal of

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BiodiversityInternational Journal of

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ScientificaHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

OceanographyInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Journal of Computational Environmental SciencesHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

ClimatologyJournal of

Page 3: Research Article Species Diversity and Tree Regeneration ...downloads.hindawi.com/archive/2013/890862.pdf · Species Diversity and Tree Regeneration Patterns in Tropical Forests of

ISRN Ecology 3

India

Wes

tern

Gha

ts

Location of NilgiriBiosphere Reserve

Nilgiri Biosphere AreaState boundary

Karnataka

GundalpetPulpally

Gudalur

OotyNAM

NilamburSV

Kerala

TamilNadu

Location of New Amarambalam RFwithin the Nilgiri Biosphere Reserve

Rivers and rivuletsForest road

35998400

11∘

25998400

11∘

76∘30

99840076

∘40

9984007

0 45 9

6∘50

99840076

∘60

998400 E

EWN

S2554 m

(kilometers)

Tropical broad-leaved drought deciduous forests (DECI)Tropical lowland semideciduous seasonal forests (SEMI)Tropical lowland broad-leaved seasonal evergreen forests (EVER)Tropical broad-leaved submontane forests (SUBM)Tropical broad-leaved drought deciduous woodlands (WOOD)Tropical broad-leaved montane forests (MONT)

Figure 1 Location and area maps of New Amarambalam Reserve Forests and adjoining forests

[50] divided percent frequency into five classes A (0ndash20)B (21ndash40) C (41ndash60) D (61ndash80) and E (81ndash100) toassess distribution of species Frequency diagrams representthe homogeneity or heterogeneity of a community as floristicuniformity varies with the value for classes A and E Whenclasses A B and C are relatively frequent the stand isheterogeneous and the greater the frequency of class E thegreater the homogeneity To assess girth pattern ghb of trees(gt10 cm gbh) of all the vegetation types was measured andcategorized into different girth class interval of 50 cm

24 Regeneration The regeneration status of a tree speciesin a given forest type was considered ldquogoodrdquo when seedlingdensity gt sapling density gt adult tree density ldquofairrdquo whenseedling density gt sapling density le adult density ldquopoorrdquowhen the species survived in only the sapling stage but notin the seedling stage ldquononerdquo for species with no sapling orseedling stages but present as adult trees and ldquonewrdquo whenadults of a species were absent but sapling andor seedlingstage(s) were present [31]When a species frequency distribu-tion fits a ldquoreverse Jrdquo pattern (high number of individuals in

4 ISRN Ecology

Table 1 Dominant trees (first three) and their densities (trees haminus1) in three different growth phases of six vegetation types International(UNESCO) and regional (Champion and Seth 1968lowast) terminology of vegetation types used See ldquoregenerationrdquo in Section 2 for procedureused to distinguish dominant species

Vegetation types Dominant species Density of tree phasesUNESCO Champion and Seth (1968) Mature Saplings Seedlings

Tropical broad-leaveddrought deciduousforests(DECI)

Southern tropical moistdeciduous forests

Xylia xylocarpa 259 23 3166Terminalia paniculata 228 52 333Lagerstroemiamicrocarpa 156 12 mdash

Wrightia tinctoria 108 86 166Holarrhena pubescens mdash 25 4833Bridelia airy-shawii 03 02 4666Radermachera xylocarpa 13 1 3500

Tropical lowlandbroad-leavedsemideciduous seasonalforests(SEMI)

West coast tropicalsemievergreen forests

Pterygota alata 49 815 245Reinwardtiodendronanamalaiense 30 85 3845

Strombosia zeylanica 16 85 456Palaquium ellipticum 14 96 240Xylia xylocarpa 19 12 96Calophyllum polyanthum 36 55 453

Tropical lowlandbroad-leaved seasonalevergreen forests(EVER)

West coast tropical evergreenforests

Palaquium ellipticum 93 38 4136Agrostistachys borneensis 71 69 223Myristica beddomei 39 27 573Reinwardtiodendronanamalaiense 28 56 1636

Calophyllum polyanthum 4 15 1042

Tropical broad-leaveddrought deciduouswoodlands(WOOD)

Subtropical hill savannahs

Wendlandia thyrsiflora 17 36 356Phyllanthus emblica 32 mdash mdashGlochidion ellipticum 23 24 mdashGnidia glauca 238 18 160Macaranga peltata 159 4 mdashErythrina stricta 08 16 80

Tropical broad-leavedevergreensubmontaneforests (SUBM)

Southern subtropicalbroad-leaved hill forests

Myristica beddomei 88 05 765Palaquium ellipticum 55 15 298Litsea stocksii 32 35 456Litsea floribunda 4 5 371

Tropical broad-leavedevergreenmontaneforests(MONT)

Southern montane wettemperate forests

Turpinia cochinchinensis 116 46 1855Rhododendron arboreum 102 34 206Symplocos obtusa 64 33 386Rhodomyrtus tomentosa 26 44 234Syzygiumcalophyllifolium 77 20 868

Litsea floribunda 30 7 870lowastChampion H G and Seth S K 1968 A revised survey of the forest types of India Oxford UK and IBH Publications New Delhi India

the seedling stage and gradually declining numbers throughthe sapling small tree and mature tree phases) that specieswas recognized as the dominant in the whole stand In orderto measure number of species shared between mature andregenerating phases Sorenson index of similarity [49] wasused 119878 = 2 119888(119886 + 119887) where 119878 is Sorenson index of similarity

119888 is number of species shared between growth phases (heremature tree phase and regenerating phase ie saplings +seedlings) 119886 is total number of species in growth phase 119886and b is total number of species in growth phase b Speciesis considered as new recruit when there was no tree specieswith mature (adult) stage

ISRN Ecology 5

58

100 98

17

75

3241

9181

17

64

3133

83 78

9

65

27

71

127 122

28

92

43

0

20

40

60

80

100

120

140

DECI SEMI EVER WOOD SUBM MONT

Num

ber o

f spe

cies

Vegetation types

Mature treesSaplings

SeedlingsTotal species

Figure 2 Species richness (number of species) by tree growth phase in six vegetation types occurring in the Western Ghats Multiplecomparison LSD post hoc test showed richness of all the vegetation types was significantly different (119875 lt 001ndash005) See Table 1 for anexplanation of vegetation type abbreviations

25 Statistical Analysis One-way ANOVA was used to testdifferences of density (ge30 cm gbh) overall species rich-ness and basal area among vegetation types LSD post hoctests were used to detect significant pair wise differencesamong means of dependent variables One-way analysisof covariance (ANCOVA) was conducted to test of thecovariate (abundance) is that it evaluates the relationshipbetween the covariate (abundance) and the dependant vari-able (species richness) controlling for the factor (vegetationtypes) Pearson correlation coefficients were calculated todetect significant correlations among vegetation parametersespecially cumulative species richness and abundance of eachvegetation typeWe used the statistical package SPSS (Version16 www-01ibmcomsoftwareanalyticsspss) for all testsFor rarefaction we used statistical software Biodiversity Pro(httpwwwsmiacukpeter-lamontbiodiversity-pro)

3 Results

31 Species Diversity In the six vegetation types sampled inthe study area there were 257 tree species belonging to 62families and 147 genera of angiosperms Richness of treespecies (Figure 2) was highest in SEMI (127 spp) and lowestin theWOOD (28 spp) Species-area and species-individualsaccumulation curve (rarefaction curve) against equal-sizedsampling areas in different vegetation types showed a distinctdifference in the richness and abundance Rarefaction canbe used to examine the evenness of the distribution ofspecies in assemblages by comparing steepness of curvesSteeper rarefaction curves indicate high heterogeneity Onestriking results of rarefaction curves was that SEMI andEVER have the highest curves This means that speciesdiversity per equal-sized area was highest in these vegetationtypes but MONT has the most individuals per unit areaVegetation type at other extreme (low species richness) wasWOOD and MONT (Figure 3) The overall difference inspecies richness among six vegetation types was statisticallysignificant (119865

5179= 651 119875 lt 00001) Species richness

and corresponding abundance were significantly positivelycorrelated in all the vegetation types (DECI 119903 = 098 119875 lt00001) SEMI 119903 = 095 119875 lt 00001 EVER 119903 = 094 119875 lt00001 WOOD 119903 = 077 119875 lt 00001 SUBM 119903 = 095 119875 lt00001 MONT 119903 = 087 119875 lt 00001) A primary analysisevaluating the homogeneity-of-regression (slopes) assump-tion indicated that the relationship between the covariate(abundance) and the dependant variable (species richness)differs significantly as a function of the independent variable(vegetation types) (1198772 = 0152 ANCOVA 119865

6179= 1334

119875 lt 0001) A significant interaction between the covariateand the factor suggests that the differences on the dependentvariable among groups vary as a function of the covariateSince the result from the ANCOVA was significant it is notmeaningful to proceed further The highest Shannon indexvalue occurred in SEMI (367 for plants with gbh ge 30 cm)and lowest value reported in WOOD (Table 2)

Dominant tree species in mature and sapling stages weremore or less similar in most vegetation types but dominantspecies in the seedling stage varied considerably (Table 1)Overall stand density of mature trees (ge30 cm gbh) washighest in MONT (855 trees haminus1) and lowest in WOOD(39 trees haminus1) Densities of both tree saplings and seedlingswere highest in EVER (Figure 4) Among 25 tree speciesdominant across the different forest types 16 dominated inthe tree phase 15 in the sapling phase and 14 in the seedlingphase Among the different forest types therewere significantdifference in tree (ge30 cm gbh) density (119875 lt 00001 119865

5389=

269) and basal area (119875 lt 0007 1198655389= 33) Mean basal

area of trees was highest in EVER (48m2 haminus1) and lowest inWOOD (Table 2)

Raunkiaerrsquos frequency analyses revealed that most ofthe tree species were rare as in the case for other tropicalforests In all forest types 60ndash95 of tree species werein the lowest frequency class (Figure 5) Furthermore therewere few individuals in the 80ndash100 frequency class Inforest types other than DECI 58ndash70 of trees were in thesmallest girth category (gbh 50ndash100 cm) in DECI only 37

6 ISRN Ecology

DECISEMIEVER

WOODSUBMMONT

120

100

80

60

40

20

0

Spec

ies

0 05 1 15 2 25Area (ha)

(a)

0

20

40

60

80

100

120

140

0 200 400 600 800 1000 1200 1400 1600 1800

Spec

ies

Individuals

DECISEMIEVER

WOODSUBMMONT

(b)

Figure 3 Species accumulation and rarefaction curves of different vegetation types Curves were created random series of 30 plots of 009 ha(ie 27 ha for each vegetation type) (a) Species-area curves (sample-based rarefaction) and (b) species-individuals curve (individuals-basedrarefaction) Looking at the individual-based rarefaction curve all four vegetation types seem to be quite similar in species richness exceptMONT which is drastically lower although containing the highest number of individuals WOOD which contain too few individuals toproduce a comparable result The sample-based rarefaction on the other hand identifies SEMI and EVER as the two most species richcommunities differing from the rest Rarefaction curves for six vegetation types predict the rate of accumulation of species with increasingnumber of individuals (abundance) See Table 1 for an explanation of vegetation type abbreviations

Table 2 Vegetation parameters calculated for three tree phases in different vegetation types See Table 1 for explanation of vegetation typeabbreviations

Vegetation types(Altitude range)

Rainfall(mm)

Mean temperaturein the coldestmonth (∘C)

Phases oftrees

Basal area(m2ha)

Shannonindex

DECI(40ndash400m) 1000ndash1500 28

Mature treesSaplingsSeedlings

2332020mdash

279248262

SEMI(400ndash650m)

2500ndash3500 24 Mature treesSaplingsSeedlings

4566089mdash

367315311

EVER(650ndash1200m)

3500ndash5000 22 Mature treesSaplingsSeedlings

4800124mdash

334309349

WOOD(900ndash1400m)

3500ndash5000 25 Mature treesSaplingsSeedlings

06904mdash

221216156

SUBM(1200ndash1800m)

5000ndash6000 13 Mature treesSaplingsSeedlings

3651069mdash

326345351

MONT(1800ndash2450m)

5000ndash6000 9 Mature treesSaplingsSeedlings

3087145mdash

321319271

lowastMature trees (ge30 cm gbh) saplings (ge 10lt 30 cm gbh) and seedlings (lt10 cm gbh)

of trees were in the smallest girth class (Figure 6) In WOODvegetation which was fire affected and grass dominated 96of trees were in the smallest girth class

32 Regeneration Frequencies of regenerating species(saplings + seedlings) were maximal in undisturbed forestcompared to disturbed one (caused by fuel wood collection

and cattle grazing) In DECI of 71 taxa recorded only 26were present in all three growth phases 24 were presentin only one stage and only 10 species were regeneratingwell (seedling gt sapling gt tree) Nevertheless Lagerstroemiamicrocarpa one of the dominant species in DECI hadno seedlings indicative of poor regeneration potential(Tables 1 and 3 see Supplementary Material Appendix 1available online at httpdxdoiorg1011552013890862)

ISRN Ecology 7

Table 3 Distribution pattern of mature and regenerating phases of trees occur in different vegetation types Regenerating species and speciesshare in all phases of trees was lower in disturbed vegetation type such as DECI and WOOD as compared to other vegetation types Percentsimilarity in species composition (using Sorenson index of similarity) of mature trees and regenerating individuals (saplings + seedlings) indifferent vegetation types of the study area and new species recruited (trees devoid of adult stage) are also shown

Vegetationtypes

Tree species occur inlowastRegeneratingspecies ()

Similarity betweenmature trees andregenerating individuals

New entryspecies ()All phases () Mature phase

only ()Regeneratingphase only ()

DECI 26 (37) 21 (30) 12 (17) 50 (70) 69 12 (17)SEMI 53 (41) 11 (9) 27 (21) 116 (91) 82 24 (18)EVER 49 (40) 11 (9) 24 (20) 111 (91) 81 23 (18)WOOD 8 (29) 8 (29) 11 (39) 20 (71) 49 10 (35)SUBM 40 (43) 4 (4) 18 (20) 87 (95) 88 20 (21)MONT 20 (47) 6 (14) 11 (26) 37 (86) 76 10 (23)lowastA number of species occur in saplings andor seedlings and these species may or may not have mature tree stage of species has been given in brackets

132 36

8

485

39

390 85

5

65

250 393

77

215 39

22073 95

57

7717

795

6971 16

395

1

10

100

1000

10000

100000

DECI SEMI EVER WOOD SUBM MONT

Den

sity

Vegetation types

Mature treesSaplingsSeedlings

Figure 4 Densities (no haminus1 in log10scale) of mature trees (ge30 cm

gbh (girth at breast height)) saplings (ge 10 lt 30 cm gbh) and seedl-ings (lt10 cm gbh) in six vegetation types occurring in the WesternGhats LSD post hoc test clarified that density of disturbed forestlike DECI and WOOD was significantly different with undisturbedvegetation type except MONT

In vegetation types influenced by disturbance and firelike WOOD 29 of species were common in all growthphases and seedling richness was very low in these types ofvegetation (Supplementary Material Appendix 2)

In vegetation types at mid elevations namely EVERand SEMI 49ndash53 of species were present in all growthphases 25ndash30 of species occurred in only one phase(Supplementary Material Appendices 3 and 4) In forestsat higher elevations namelySUBM and MONT 43 and47 of species respectively were present in all growthphases In SUBM 25 species had poor regeneration potential(Supplementary Material Appendix 5) In MONT 20 specieswere present in all growth phases and 12 had no regenerationpotential (Table 3 Supplementary Material Appendix 6)

33 Change in Species Composition among Tree Phases Over-all species richness of mature trees was higher than richnessof saplings and seedlings in all vegetation types Among the

dominant species a few trees had exceptionally large num-bers of seedling and saplings Individual trees did notcontribute equally to the seedling population or to laterrecruitment in the sapling stage Density of regeneratingindividuals (saplings + seedlings) was highest in EVER andlowest in WOOD There was significant difference in thedensity of regenerating individuals (seedling + saplings)among different vegetation types (119865

5611= 132 119875 lt 0001)

Also there was significant difference in the density of matureand regenerating phase among all vegetation types exceptWOOD (DECI 119865

1130= 117 119875 lt 0001 SEMI 119865

1269= 37

119875 lt 005 EVER 1198651255= 73 119875 lt 0008 WOOD 119865

141= 34

119875 lt 0059 SUBM 1198651201= 101 119875 lt 0002 MONT 119865

188=

51 119875 lt 0026)The overall changes in species composition from mature

stage to regenerating stage (sapling + seedling phases) ofdifferent vegetation types 21 that is 79 similarity (usingSorenson index of similarity) between mature and regenerat-ing phase In disturbed WOOD and DECI the similarity inspecies composition between mature trees and regeneratingindividuals was 49 and 69 respectively In little-disturbedvegetation types species similarity between mature trees andregenerating phases was relatively high In all the forest typesnew entry species (tree species with no adult stages) werepresent Percent of new entry species was highest in fireaffected WOOD vegetation (Table 3)

4 Discussion

41 Species Diversity Theuse of species-individuals curves inaddition to species-area curves provides a clear insight intospecies diversity More sampling area is required for speciesrich vegetation type compared to species poor one and ingeneral the minimum area varies with number of speciesfrom one vegetation type to another [51] In our data species-rich communities like SEMI and EVER seem to have lessdominance than species-poor communities However lowerrarefaction curve in MONT suggests that abundance effectmay not be the sole reason for high richness The accumu-lation of new species with increasing sampling effort canbe visualized with a species accumulation curve Increasing

8 ISRN Ecology

0

20

40

60

80

100

Frequency classes

DECI

0ndash20 21ndash40 41ndash60 61ndash80 81ndash100

Spec

ies (

)

(a)

0

20

40

60

80

100SEMI

Frequency classes0ndash20 21ndash40 41ndash60 61ndash80 81ndash100

Spec

ies (

)

(b)

0

20

40

60

80

100

EVER

Frequency classes0ndash20 21ndash40 41ndash60 61ndash80 81ndash100

Spec

ies (

)

(c)

0

20

40

60

80

100

WOOD

Frequency classes0ndash20 21ndash40 41ndash60 61ndash80 81ndash100

Spec

ies (

)

(d)

0

20

40

60

80

100

SUBM

Frequency classes0ndash20 21ndash40 41ndash60 61ndash80 81ndash100

Mature treesSaplingsSeedlings

Spec

ies (

)

(e)

0

20

40

60

80

100

MONT

Mature treesSaplingsSeedlings

Frequency classes0ndash20 21ndash40 41ndash60 61ndash80 81ndash100

Spec

ies (

)

(f)

Figure 5 Percent frequencies of trees (ge30 cm gbh) in different vegetation types Most of the species were in the lowest frequency class inall vegetation types other than MONT indicating that a few species were widely distributed most were restricted in distribution This is atypical species-abundance distribution (normal distribution) and the tree species in all the vegetation type were heterogeneous distributionin Raunkiaerrsquos sense

the area sampled increases observed species richness bothbecause more individuals get included in the sample andbecause large areas are environmentally more heterogeneousthan small areas [52] The correlation between species rich-ness and abundance suggests that process affecting change ineither richness or abundance also affects species diversity

Species richness of DECI was reduced likely due to lowrainfall and anthropogenic disturbances such as firewoodcollection and cattle grazing In fire affected WOOD grasseswere the dominant life forms these were intermingled with afew fire tolerant light demanding trees High species richnessof trees in SEMI EVER and SUBM was probably relatedto high rainfall and optimal climatic conditions (Table 2)Low temperature and high wind velocity in the MONT may

negatively impact tree growth and reduce species richnessthere DECI standswere dominated bymembers of the familyFabaceae while Euphorbiaceae and Rubiaceae dominated inEVER at mid elevations High elevation SUBM and MONTwere dominated bymembers of the Lauraceae andMyrtaceaewhich have volatile oils in their tissues that resist freezingdamage in plant cells [53]

Compared to DECI tree species diversity was very highin other forest types at higher elevations other than in thefire-affected WOOD High species diversity of SEMI is dueits transitional nature that is this vegetation type is ecotonearea suitable for both deciduous and evergreen tree species sothere is an increase in the number of species Species diversityindices for saplings were lower than those for mature trees

ISRN Ecology 9

3721 19 10 6 3 2 1 1

020406080

100DECI

Tree

s (

)

Girth classes

10ndash5

0

101ndash

150

151ndash

200

201ndash

250

251ndash

300

301ndash

350

351ndash

400

51ndash1

00

gt400

(a)

020406080

10060

20 9 3 2 2 21 1

SEMI

Tree

s (

)

Girth classes

10ndash5

0

101ndash

150

151ndash

200

201ndash

250

251ndash

300

301ndash

350

351ndash

400

51ndash1

00

gt400

(b)

020406080

10065

19 9 3 2 2 21 1

EVER

Tree

s (

)

Girth classes

10ndash5

0

101ndash

150

151ndash

200

201ndash

250

251ndash

300

301ndash

350

351ndash

400

51ndash1

00

gt400

(c)

020406080

100 96

4 0 0 0 0 0 0 0

WOOD

Tree

s (

)

Girth classes

10ndash5

0

101ndash

150

151ndash

200

201ndash

250

251ndash

300

301ndash

350

351ndash

400

51ndash1

00

gt400

(d)

020406080

10058

20 12 4 2 1 1 1 1

SUBM

Girth classes

10ndash5

0

101ndash

150

151ndash

200

201ndash

250

251ndash

300

301ndash

350

351ndash

400

Tree

s (

)

51ndash1

00

gt400

(e)

020406080

10070

243 2 1 0 0 0 0

MONT

Tree

s (

)

Girth classes

10ndash5

0

101ndash

150

151ndash

200

201ndash

250

251ndash

300

301ndash

350

351ndash

400

51ndash1

00

gt400

(f)

Figure 6 Girth frequency distributions of trees in different vegetation types of the study area Girth-size was highest in SEMI and EVER Ahigh percentage of lower girth class trees in DECI results from reduced fuel wood extraction by people of nearby areas The reverse J-shapedgbh distribution of trees indicates evolving or expanding population

and seedlings in DECI is due to overharvesting of saplingsfor firewood The lowest species diversity value in WOODindicates low species richness and dominance of one or twospecies in the tree community In the present study Shannonindex values for tree species are similar to values for othertropical forests of the world (Table 4) However detailedcomparisons with other studies are inadvisable because oflarge differences in sample size standard girth parametersand environmental conditions

Density and frequency distributions of trees contributeto the structure of tropical forests Tree density in DECI wasmuch lower than that of other forest types perhaps due to lowrainfall and anthropogenic disturbances Density was least inthe fire-affected WOOD Sapling densities were elevated inSEMI and EVER Late secondary successional species werewell represented in the sapling population of EVER whichmay be indicative of recent natural disturbances in this foresttype that promoted regeneration of late secondary speciesMONT had high sapling density due to the stunted nature oftrees caused by very low temperature and high wind velocityprevalent there [54]

Densities of trees in the study area were similar toestimates from tropical forests within India and other tropicalregions (Table 4) In tropical forests outside India there ismuch variation in the densities of trees gt30 cm gbh (98ndash1930 trees haminus1) especially in Amazonian forests In theNeotropics maximum species richness of tree individualsgt10 cm gbh reaches 300 haminus1 [55] In South-East Asia thehighest richness is 225 haminus1 [56]

In the present studymost of the species were in frequencyclass 0ndash20 and fewest were in frequency class 80ndash100The frequency distribution of tree species suggested thatmostof them had low frequency as would be expected in typicalspecies-abundance distribution A plant species should beconsidered homogeneously distributed when the numbersof individuals are the same in all parts of a community[50] Hence tree species in all the vegetation types of thestudy area were heterogeneously distributed Girth classfrequency distributions of most species in vegetation typeswe studied fit ldquoreverse Jrdquo-shaped patterns with most trees insmaller girth classes and few old trees Vegetation types otherthan WOOD fit negative exponential patterns indicative of

10 ISRN Ecology

Table4Ve

getatio

nparameterso

fforestcom

mun

ities

inthetropics

ofIndiaa

ndotherc

ountrie

s

Foresttypes

Locatio

nPlot

size(ha)

Tree

girth

studied

(cm)

Tree

density

(noha)

Tree

basal

area

(m2 ha)

Shanno

nindex

References

Presentstudy

DEC

IWestern

Ghats(N

BR)

4ha

ge30

cm132

234

279

Present

study

SEMI

ldquo4ha

ge30

cm368

457

367

ldquo

EVER

ldquo4ha

ge30

cm485

480

334

ldquo

WOOD

ldquo3ha

ge30

cm39

069

221

ldquo

SUBM

ldquo4ha

ge30

cm390

365

326

ldquo

MONT

ldquo4ha

ge30

cm855

309

321

ldquo

India

Evergreenforests

Silent

valleyWestern

Ghat

mdashge315

620ndash

709

29ndash103

mdash[6]

Moistdecidu

ousforests

Pepp

araWGhats

mdashge30

590ndash

740

13ndash51

2ndash33

[7]

Moistdecidu

ousforests

Chim

mon

yWestern

Ghats

mdashge30

558

3719

ndash24

[8]

Semievergreen

forests

Pepp

araWestern

Ghats

mdashge30

670ndash

940

45ndash6

229

[7]

Semievergreen

forests

Chim

mon

yWestern

Ghats

mdashge30

728

4727ndash32

[8]

Scrubjung

leto

wetevergreenforests

Kalakk

adRF

Western

Ghats

02

gt20

320ndash

1260

18ndash107

mdash[9]

Evergreenforests

Karnataka

044

mdash44

6ndash1386

33ndash4

8mdash

[10]

Evergreenforests

Pepp

ara

mdashge30

860ndash

1370

7633

[7]

Evergreenforests

NelliampathiWestern

Ghats

mdashge30

mdash498

3ndash37

[11]

Dry

tropicalforests

Vind

hyar

egion

mdashgt30

294ndash

559

7ndash23

mdash[12]

Dry

evergreenforests

Puthup

etSacred

GroveC

orom

andel

coast

02

gt20

280

11mdash

[13]

Trop

icalwe

tevergreen

forests

Kalakk

ad-M

undanthu

raiT

iger

Reserve

Western

Ghats

050

gt30

315ndash418

54ndash8

4mdash

[14]

Trop

icalwe

tevergreen

forests

KodayarWestern

Ghats

050

gt30

352ndash117

328ndash81

mdash[15]

Subtropicalh

illforests

Pepp

araWestern

Ghats

mdashge30

1580ndash1930

27ndash34

27

[7]

Mon

tane

temperateforests

Mannavanshola

mdashge30

566

52399

[16]

ISRN Ecology 11

Table4Con

tinued

Foresttypes

Locatio

nPlot

size(ha)

Tree

girth

studied

(cm)

Tree

density

(noha)

Tree

basal

area

(m2 ha)

Shanno

nindex

References

Other

coun

tries

Trop

icalrain

forests

(you

ngforests

)Ba

rrow

ColoradoIsland

Panam

a5

gt18

84ndash171

26ndash

52

mdash[17]

Trop

icalrain

forests

(old

forests

)Ba

rrow

ColoradoIsland

Panam

a50

gt18

143ndash177

43ndash5

mdash[18]

Trop

icalrain

forests

Amazon

ia3

314

1420

28ndash6

8mdash

[19]

Equatoria

linsular

forests

Easte

rnCa

rolline

Island

Panam

a50

gt314

98ndash114

17mdash

[20]

Trop

icalrain

forests

Jung

kaRe

serveMalaysia

1191

104

23mdash

[21]

Trop

icalrain

forests

Gun

ungSilamM

alaysia

004

314

513ndash1596

23ndash4

6mdash

[22]

Trop

icalmoistforests

Sing

apore

04

gt63

604

mdashmdash

[23]

Trop

icalrain

forests

Valcan

BarvaCostaRica

6gt314

391ndash617

mdashmdash

[24]

Slop

eforests

New

Caledo

nia

28

gt314

1533

49mdash

[25]

Allu

vium

forests

New

Caledo

nia

26

gt314

1183

47mdash

[25]

Equatoria

lforests

KongoIsland

mdashmdash

440ndash

553

10ndash4

5mdash

[26]

Trop

icalrain

forests

Amazon

ia3

gt314

1720

78mdash

[19]

Trop

icalseason

alrain

forests

Xishuang

bann

aCh

ina

2500

m2

15154

mdash34

[27]

Trop

icalmon

tane

rain

forests

Xishuang

bann

aCh

ina

1600

m2

15123

mdash32

[27]

Evergreenbroadleaved

forests

Xishuang

bann

aCh

ina

1200

m2

15165

mdash25

[27]

Mon

soon

forests

Xishuang

bann

aCh

ina

400m

210

150

mdash16

[27]

ldquoStudy

cond

uctedin

6different

vegetatio

ntypeso

fWestern

Ghats(N

BR)

12 ISRN Ecology

relatively undisturbed or less disturbed conditions in thestands The high annual precipitation rate and optimumtemperature of EVER may have contributed to high treegrowth rate and higher tree basal area

42 Regeneration All other vegetation types had betterregeneration than DECI In WOOD the transition rate ofstems from small girth classes to larger girth classes was lowPoor tree regeneration in DECI and WOOD can probablybe attributed to fuel wood collection frequent fires andgrazing by cattle In all forest types 29ndash47 of tree specieswere present in all three growth phases other species werepresent in either one or two growth phases Dominant speciesoccurred in all girth classes of vegetation types other thanWOOD in whichmost trees were in the smaller girth classesThere were more large trees in vegetation types like SEMIand EVER and in these sapling and seedling densities wereadequate for restocking the complement of canopy trees

Change in species composition across mature and regen-erating tree phases was more frequent in disturbed foresttypes like DECI and WOOD In some cases the dominantspecies in adult and seedling stages were quite differentin these two disturbed forest types Our results are notcongruent with observationsmade in northeastern India [39]where tree seedling survival rate increases with increasingforest disturbance We found species without regeneratingphases these are unlikely to persist Others that occurred onlyin seedling and sapling stages were new entrants to the forestspecies complement These are examples of discontinuouspopulation structures Such structures occur in a number ofother tropical countries [57ndash59] The dominant species in aforest stand is generally present in all size classes [38] Thesize class structures of trees indicate the probability of speciespersistence into the future this information is very valuablein the design of management strategies aiming to improvestand structure and species diversity Changes in speciescomposition and recruitment of new species in differentvegetation types are indicative of future species compositionin changing environments

5 Conclusions

The species diversity of trees varied across vegetation types inthe Western Ghats landscape Rarefaction curves show thatspecies diversity is highest in SEMI and EVER and lowest inWOOD while species abundance is highest in MONT Vege-tation types of study area are in heterogeneous in distributionThere were large differences in species composition of adulttrees and regenerating individuals in the disturbed vegetationtypes as compared to undisturbed stands The present studyreveals that the anthropogenic disturbance causes disruptionof forest structure and change in species composition whichultimately leads to reduction of tree species richness andabundance which are the major attributes of forests Newrecruits were found in all vegetation types indicating thattheywere not headed to extinction however disturbed standsmay move to new species compositions in the future

Acknowledgments

The authors are thankful to the Ministry of Environmentand Forests for financial support and the Vice Chancellorof University of Delhi and the Director of Kerala ForestResearch Institute for facilities provided The first authorwould like to thank Professor C R Babu for facilities andencouragement The authors are very much obliged to allmembers of the Cholanaikkan tribe who helped duringthe field survey The Kerala Forest Department provided alllogistical support for the floristic and ecological survey of theforest area (trees haminus1) in three different growth phases of sixvegetation

References

[1] M A Huston Biological Diversity The Coexistence of Species inChanging Landscapes Cambridge University Press CambridgeUK 1994

[2] T C Whitmore An Introduction to Tropical Rain ForestsOxfordUniversity Press NewYork NYUSA 2nd edition 1998

[3] M L Khan S Menon and K S Bawa ldquoEffectiveness of theprotected area network in biodiversity conservation a case-study of Meghalaya staterdquo Biodiversity and Conservation vol 6no 6 pp 853ndash868 1997

[4] C M Pringle ldquoNutrient spatial heterogeneity effects on com-munity structure physiognomy and diversity of stream algaerdquoEcology vol 71 no 3 pp 905ndash920 1990

[5] M Parviainen M Marmion M Luoto W Thuiller and RK Heikkinen ldquoUsing summed individual species models andstate-of-the-art modelling techniques to identify threatenedplant species hotspotsrdquo Biological Conservation vol 142 no 11pp 2501ndash2509 2009

[6] J S Singh S P Singh A K Saxena and Y S Ravat ldquoThe forestvegetation of Silent Valleyrdquo in Tropical Rain Forests The LeedsSymposium pp 25ndash52 1984

[7] A O Varghese ldquoAssessment of biodiversity of PepparaWildlifeSanctuary Trivandrum District Keralardquo Journal of Economicand Taxonomic Botany vol 23 pp 117ndash127 1998

[8] M A Suraj Phytosociological and vagetation mapping at chim-mony wildlife Sanctuary (Kerala) using remote sensing technique[PhD thesis] FRI University Dehradun India 1997

[9] N Parthasarathy Studies on the vacular flora structure andnutrient cycling in Kalakad Reserve Forest Western Ghats TamilNadu [PhD thesis] University of Madras Tamil Nadu India1986

[10] S N Rai and J Proctor ldquoEcological studies on four rainforests in Karnataka India environment forest structure andvegetationrdquo Journal of Vegetation Science vol 1 pp 609ndash6141986

[11] U M Chadrashekara A R R Menon K K N Nair NSasidharan and K Swarupanandan ldquoEvaluating plant diversityin different forest types of Kerala by laying out permanent sam-ple plotsrdquo KFRI Research Report 156 Kerala Forest ResearchInstitute Peechi India 1998

[12] C S Jha and J S Singh ldquoComposition and dynamics of drytropical Forest in relation to soil texturerdquo Journal of VegetationScience vol 1 no 5 pp 609ndash614 1990

[13] NVisalakshi ldquoVegetation analysis of two tropical dry evergreenforests in southern IndiardquoTropical Ecology vol 36 no 1 pp 117ndash127 1995

ISRN Ecology 13

[14] T Ganesh R Ganesan M Soubadra Devy P Davidar and K SBawa ldquoAssessment of plant biodiversity at amid-elevation ever-green forest of Kalakad-Mundanthurai Tiger Reserve WesternGhats Indiardquo Current Science vol 71 no 5 pp 379ndash392 1996

[15] S M Sundarapandian and P S Swamy ldquoForest ecosystemstructure and composition along an altitudinal gradient in theWestern Ghats South Indiardquo Journal of Tropical Forest Sciencevol 12 no 1 pp 104ndash123 2000

[16] K Swarupanandan N Sasidharan K C Chacko and SChanduBasha ldquoFloristic and ecological studies on the Sholasof Idukki Districtrdquo in Shola Forests of Kerala Environmentand Biodiverstiy K K N Nair S K Khanduri and K Bala-subramaniayan Eds pp 259ndash286 Kerala Forest DeparmentThiruvanathapuram Kerala Forest Research Institute PeechiIndia 2001

[17] R W Thorington S Tannenbaum A Tarak and R RudranldquoDistribution of trees in Baro Colorado Islands a hectaresamplerdquo in The Ecology of a Tropical Forest-Seasonal Rhythmsand Long-term Changes E G Leigh Jr A S Rand and D MWindsor Eds Smithsonian Institute Press Washington DCUSA 1982

[18] S P Hubbell and R B Foster ldquoDiversity of canopy speciesin a neotropical forest and implications for conservationrdquo inTropical Rain Forest Ecology and Management S L Sutton TCWhitmore andA C Chadwick Eds Blackwell Oxford UK1983

[19] D G Campbell D C Daly G T Prance and U N MacielldquoQuantitative ecological inventory of terra firme and varzeatropical forest on the Rio Xingu Brazilian Amazonrdquo Brittoniavol 38 no 4 pp 369ndash393 1986

[20] S Itow ldquoSpecies diversity of equatorial insular forests on Ponapeand Kosrae Micronesiardquo Ecological Research vol 1 no 2 pp223ndash227 1986

[21] C C Ho D M Newbery and M E D Poore ldquoForestcomposition and inferred dynamics in Jengka Forest ReserveMalaysiardquo Journal of Tropical Ecology vol 3 no 1 pp 25ndash561987

[22] J Proctor Y F Lee A M Langley W R C Munro and TNelson ldquoEcological studies onGunung Silam a small ultrabasicmountain Sabah Malaysiardquo Journal of Ecology vol 74 pp 455ndash463 1988

[23] F R Swan Jr ldquoTree distribution patterns in the Bukittimahnature reserve Singaporerdquo Gardens Bulletin vol 41 pp 59ndash811988

[24] A Heaney and J Proctor ldquoPreliminary studies on foreststructure and floristics on Volcan Barva Costa Ricardquo Journalof Tropical Ecology vol 6 no 3 pp 307ndash320 1990

[25] T Jaffre and J M Veillon ldquoEtude floristique et structuralede deux forets denses humides sur roches ultrabasiques enNouvelle- Caledonierdquo Bulletin du Museum National drsquoHistoireNaturelle vol 12 pp 243ndash273 1990

[26] MMosango ldquoContribution ldquoA lrsquoetude botanic biogeo 1rdquo ecosys-tem Foret en region equatorial (Ile KongoloZaire)rdquo BelgiumJournal of Botany vol 124 pp 167ndash194 1991

[27] M Cao and J Zhang ldquoTree species diversity of tropical forestvegetation in Xishuangbanna SW Chinardquo Biodiversity andConservation vol 6 no 7 pp 995ndash1006 1997

[28] C S Jha L Goparaju A Tripathi B Gharai A S Raghubanshiand J S Singh ldquoForest fragmentation and its impact onspecies diversity an analysis using remote sensing and GISrdquoBiodiversity and Conservation vol 14 no 7 pp 1681ndash1698 2005

[29] P S Roy C B S Dutt and P K Joshi ldquoTropical forest resourceassessment and monitoringrdquo Tropical Ecology vol 43 no 1 pp21ndash37 2002

[30] R Sagar A S Raghubanshi and J S Singh ldquoAsymptoticmodelsof species-area curve for measuring diversity of dry tropicalforest tree speciesrdquo Current Science vol 84 no 12 pp 1555ndash1560 2003

[31] R Sukumar H S Dattaraja H S Suresh et al ldquoLong-termmonitoring of vegetation in a tropical deciduous forest inMudumalai southern Indiardquo Current Science vol 62 pp 608ndash616 1992

[32] UMChandrashekara and P S Ramakrishnan ldquoVegetation andgap dynamics of a tropical wet evergreen forest in the WesternGhats of Kerala Indiardquo Journal of Tropical Ecology vol 10 no3 pp 337ndash354 1994

[33] T Ganesh R Ganesan M Soubadra Devy P Davidar and K SBawa ldquoAssessment of plant biodiversity at amid-elevation ever-green forest of Kalakad-Mundanthurai Tiger Reserve WesternGhats Indiardquo Current Science vol 71 no 5 pp 379ndash392 1996

[34] J P Pascal and R Pelissier ldquoStructure and floristic compositionof a tropical evergreen forest in south-west Indiardquo Journal ofTropical Ecology vol 12 no 2 pp 191ndash210 1996

[35] N Ayyappan and N Parthasarathy ldquoBiodiversity inventory oftrees in a large-scale permanent plot of tropical evergreen forestat Varagalaiar Anamalais Western Ghats Indiardquo Biodiversityand Conservation vol 8 no 11 pp 1533ndash1554 1999

[36] A Kumar B G Marcot and A Saxena ldquoTree species diversityand distribution patterns in tropical forests of Garo HillsrdquoCurrent Science vol 91 no 10 pp 1370ndash1381 2006

[37] N Parthasarathy ldquoTree diversity and distribution in undis-turbed and human-impacted sites of tropical wet evergreenforest in southern Western Ghats Indiardquo Biodiversity andConservation vol 8 no 10 pp 1365ndash1381 1999

[38] M L Khan J P N Rai and R S Tripathi ldquoPopulation structureof some tree species in disturbed and protected subtropicalforests of north-east Indiardquo Acta Oecologica vol 8 no 3 pp247ndash255 1987

[39] R S Tripathi and M L Khan ldquoRegeneration pattern andpopulation structure of trees in subtropical forest of North EastIndiardquo in Tropical Ecosystem-Ecology and Management K PSingh and J S Singh Eds pp 431ndash441 Wiley Eastern LimitedNew Delhi India 1992

[40] A E Scholl and A H Taylor ldquoRegeneration patterns in old-growth red fir-western white pine forests in the northern SierraNevada Lake Tahoe USArdquo Forest Ecology and Managementvol 235 no 1ndash3 pp 143ndash154 2006

[41] D A Clark ldquoRegeneration of canopy trees in tropical wetforestsrdquo Trends in Ecology and Evolution vol 1 no 6 pp 150ndash154 1986

[42] P C J Barker and J B Kirkpatrick ldquoPhyllocladus aspleniifoliusvariability in the population structure the regeneration nicheand dispersion patterns in Tasmanian forestsrdquo Australian Jour-nal of Botany vol 42 no 2 pp 163ndash190 1994

[43] C K Augspurger ldquoSeedling survival of tropical tree speciesinteractions of dispersal distance light-gaps and pathogensrdquoEcology vol 65 no 6 pp 1705ndash1712 1984

[44] O L Phillips ldquoLong-term environmental change in tropicalforests increasing tree turnoverrdquo Environmental Conservationvol 23 no 3 pp 235ndash248 1996

[45] Ministry of Environment and Forests ldquoPlant discoveries 2011newgenera species andnew recordsrdquo Botanical Survey of IndiaMinistry of Environment and Forests New Delhi India 2012

14 ISRN Ecology

[46] ldquoWeblink 2007rdquo httpwwwbiodiversityhotspotsorgxphot-spotshotspots by region

[47] D Mueller-Dombois and H Ellenberg Aims and Methods ofPlant Ecology John Wiley amp Sons New York NY USA 1974

[48] K K N Nair and R Jayakumar ldquoPhytogeography endemismand affinities of the flora of NewAmarambalamReserve Forestsin theWesternGhats of Indiardquo Indian Journal of Forestry vol 31pp 85ndash94 2008

[49] A E Magurran Ecological Diversity and Its MeasurementCroom Helm Ltd London UK 1988

[50] C Raunkiaer The Life Forms of Plants and Statistical PlantGeography Clarendon Press Oxford UK 1934

[51] B Rice andMWestoby ldquoPlant species richness at the 01 hectarescale in Australian vegetation compared to other continentsrdquoVegetatio vol 52 no 3 pp 129ndash140 1983

[52] SM Scheiner ldquoSix types of species-area curvesrdquoGlobal Ecologyand Biogeography vol 12 no 6 pp 441ndash447 2003

[53] H G Jones Plants and Microclimate Cambridge UniversityPress Cambridge UK 1983

[54] N C Nair The Southern Western Ghats A Biodiversity Con-servation Plan Indian National Trust for Arts and CulturalHeritage New Delhi India 1991

[55] AHGentry ldquoChanges in plant community diversity and floris-tic composition on environmental and geographical gradientrdquoAnnals of the Missouri Botanical Garden vol 75 no 1 pp 1ndash341988

[56] T CWhitmore Tropical Rain Forests of the Far East ClarendonPress Oxford UK 1984

[57] N V L Brokaw ldquoGap-phase regeneration of three pioneer treespecies in a tropical forestrdquo Journal of Ecology vol 75 no 1 pp9ndash19 1987

[58] S Itow and D Mueller-Dombois ldquoPopulation structure stand-level dieback and recovery of Scalesia pedunculata forest in theGalapagos Islandsrdquo Ecological Research vol 3 no 3 pp 333ndash339 1988

[59] T CWhitmore ldquoA review of some aspects of tropical rainforestseedling ecology with suggestions for further enquiryrdquo inEcology of Tropical Forest Tree Seedlings M D Swaine Ed pp3ndash39 UNESCOParthenon Paris France 1996

Submit your manuscripts athttpwwwhindawicom

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ClimatologyJournal of

Page 4: Research Article Species Diversity and Tree Regeneration ...downloads.hindawi.com/archive/2013/890862.pdf · Species Diversity and Tree Regeneration Patterns in Tropical Forests of

4 ISRN Ecology

Table 1 Dominant trees (first three) and their densities (trees haminus1) in three different growth phases of six vegetation types International(UNESCO) and regional (Champion and Seth 1968lowast) terminology of vegetation types used See ldquoregenerationrdquo in Section 2 for procedureused to distinguish dominant species

Vegetation types Dominant species Density of tree phasesUNESCO Champion and Seth (1968) Mature Saplings Seedlings

Tropical broad-leaveddrought deciduousforests(DECI)

Southern tropical moistdeciduous forests

Xylia xylocarpa 259 23 3166Terminalia paniculata 228 52 333Lagerstroemiamicrocarpa 156 12 mdash

Wrightia tinctoria 108 86 166Holarrhena pubescens mdash 25 4833Bridelia airy-shawii 03 02 4666Radermachera xylocarpa 13 1 3500

Tropical lowlandbroad-leavedsemideciduous seasonalforests(SEMI)

West coast tropicalsemievergreen forests

Pterygota alata 49 815 245Reinwardtiodendronanamalaiense 30 85 3845

Strombosia zeylanica 16 85 456Palaquium ellipticum 14 96 240Xylia xylocarpa 19 12 96Calophyllum polyanthum 36 55 453

Tropical lowlandbroad-leaved seasonalevergreen forests(EVER)

West coast tropical evergreenforests

Palaquium ellipticum 93 38 4136Agrostistachys borneensis 71 69 223Myristica beddomei 39 27 573Reinwardtiodendronanamalaiense 28 56 1636

Calophyllum polyanthum 4 15 1042

Tropical broad-leaveddrought deciduouswoodlands(WOOD)

Subtropical hill savannahs

Wendlandia thyrsiflora 17 36 356Phyllanthus emblica 32 mdash mdashGlochidion ellipticum 23 24 mdashGnidia glauca 238 18 160Macaranga peltata 159 4 mdashErythrina stricta 08 16 80

Tropical broad-leavedevergreensubmontaneforests (SUBM)

Southern subtropicalbroad-leaved hill forests

Myristica beddomei 88 05 765Palaquium ellipticum 55 15 298Litsea stocksii 32 35 456Litsea floribunda 4 5 371

Tropical broad-leavedevergreenmontaneforests(MONT)

Southern montane wettemperate forests

Turpinia cochinchinensis 116 46 1855Rhododendron arboreum 102 34 206Symplocos obtusa 64 33 386Rhodomyrtus tomentosa 26 44 234Syzygiumcalophyllifolium 77 20 868

Litsea floribunda 30 7 870lowastChampion H G and Seth S K 1968 A revised survey of the forest types of India Oxford UK and IBH Publications New Delhi India

the seedling stage and gradually declining numbers throughthe sapling small tree and mature tree phases) that specieswas recognized as the dominant in the whole stand In orderto measure number of species shared between mature andregenerating phases Sorenson index of similarity [49] wasused 119878 = 2 119888(119886 + 119887) where 119878 is Sorenson index of similarity

119888 is number of species shared between growth phases (heremature tree phase and regenerating phase ie saplings +seedlings) 119886 is total number of species in growth phase 119886and b is total number of species in growth phase b Speciesis considered as new recruit when there was no tree specieswith mature (adult) stage

ISRN Ecology 5

58

100 98

17

75

3241

9181

17

64

3133

83 78

9

65

27

71

127 122

28

92

43

0

20

40

60

80

100

120

140

DECI SEMI EVER WOOD SUBM MONT

Num

ber o

f spe

cies

Vegetation types

Mature treesSaplings

SeedlingsTotal species

Figure 2 Species richness (number of species) by tree growth phase in six vegetation types occurring in the Western Ghats Multiplecomparison LSD post hoc test showed richness of all the vegetation types was significantly different (119875 lt 001ndash005) See Table 1 for anexplanation of vegetation type abbreviations

25 Statistical Analysis One-way ANOVA was used to testdifferences of density (ge30 cm gbh) overall species rich-ness and basal area among vegetation types LSD post hoctests were used to detect significant pair wise differencesamong means of dependent variables One-way analysisof covariance (ANCOVA) was conducted to test of thecovariate (abundance) is that it evaluates the relationshipbetween the covariate (abundance) and the dependant vari-able (species richness) controlling for the factor (vegetationtypes) Pearson correlation coefficients were calculated todetect significant correlations among vegetation parametersespecially cumulative species richness and abundance of eachvegetation typeWe used the statistical package SPSS (Version16 www-01ibmcomsoftwareanalyticsspss) for all testsFor rarefaction we used statistical software Biodiversity Pro(httpwwwsmiacukpeter-lamontbiodiversity-pro)

3 Results

31 Species Diversity In the six vegetation types sampled inthe study area there were 257 tree species belonging to 62families and 147 genera of angiosperms Richness of treespecies (Figure 2) was highest in SEMI (127 spp) and lowestin theWOOD (28 spp) Species-area and species-individualsaccumulation curve (rarefaction curve) against equal-sizedsampling areas in different vegetation types showed a distinctdifference in the richness and abundance Rarefaction canbe used to examine the evenness of the distribution ofspecies in assemblages by comparing steepness of curvesSteeper rarefaction curves indicate high heterogeneity Onestriking results of rarefaction curves was that SEMI andEVER have the highest curves This means that speciesdiversity per equal-sized area was highest in these vegetationtypes but MONT has the most individuals per unit areaVegetation type at other extreme (low species richness) wasWOOD and MONT (Figure 3) The overall difference inspecies richness among six vegetation types was statisticallysignificant (119865

5179= 651 119875 lt 00001) Species richness

and corresponding abundance were significantly positivelycorrelated in all the vegetation types (DECI 119903 = 098 119875 lt00001) SEMI 119903 = 095 119875 lt 00001 EVER 119903 = 094 119875 lt00001 WOOD 119903 = 077 119875 lt 00001 SUBM 119903 = 095 119875 lt00001 MONT 119903 = 087 119875 lt 00001) A primary analysisevaluating the homogeneity-of-regression (slopes) assump-tion indicated that the relationship between the covariate(abundance) and the dependant variable (species richness)differs significantly as a function of the independent variable(vegetation types) (1198772 = 0152 ANCOVA 119865

6179= 1334

119875 lt 0001) A significant interaction between the covariateand the factor suggests that the differences on the dependentvariable among groups vary as a function of the covariateSince the result from the ANCOVA was significant it is notmeaningful to proceed further The highest Shannon indexvalue occurred in SEMI (367 for plants with gbh ge 30 cm)and lowest value reported in WOOD (Table 2)

Dominant tree species in mature and sapling stages weremore or less similar in most vegetation types but dominantspecies in the seedling stage varied considerably (Table 1)Overall stand density of mature trees (ge30 cm gbh) washighest in MONT (855 trees haminus1) and lowest in WOOD(39 trees haminus1) Densities of both tree saplings and seedlingswere highest in EVER (Figure 4) Among 25 tree speciesdominant across the different forest types 16 dominated inthe tree phase 15 in the sapling phase and 14 in the seedlingphase Among the different forest types therewere significantdifference in tree (ge30 cm gbh) density (119875 lt 00001 119865

5389=

269) and basal area (119875 lt 0007 1198655389= 33) Mean basal

area of trees was highest in EVER (48m2 haminus1) and lowest inWOOD (Table 2)

Raunkiaerrsquos frequency analyses revealed that most ofthe tree species were rare as in the case for other tropicalforests In all forest types 60ndash95 of tree species werein the lowest frequency class (Figure 5) Furthermore therewere few individuals in the 80ndash100 frequency class Inforest types other than DECI 58ndash70 of trees were in thesmallest girth category (gbh 50ndash100 cm) in DECI only 37

6 ISRN Ecology

DECISEMIEVER

WOODSUBMMONT

120

100

80

60

40

20

0

Spec

ies

0 05 1 15 2 25Area (ha)

(a)

0

20

40

60

80

100

120

140

0 200 400 600 800 1000 1200 1400 1600 1800

Spec

ies

Individuals

DECISEMIEVER

WOODSUBMMONT

(b)

Figure 3 Species accumulation and rarefaction curves of different vegetation types Curves were created random series of 30 plots of 009 ha(ie 27 ha for each vegetation type) (a) Species-area curves (sample-based rarefaction) and (b) species-individuals curve (individuals-basedrarefaction) Looking at the individual-based rarefaction curve all four vegetation types seem to be quite similar in species richness exceptMONT which is drastically lower although containing the highest number of individuals WOOD which contain too few individuals toproduce a comparable result The sample-based rarefaction on the other hand identifies SEMI and EVER as the two most species richcommunities differing from the rest Rarefaction curves for six vegetation types predict the rate of accumulation of species with increasingnumber of individuals (abundance) See Table 1 for an explanation of vegetation type abbreviations

Table 2 Vegetation parameters calculated for three tree phases in different vegetation types See Table 1 for explanation of vegetation typeabbreviations

Vegetation types(Altitude range)

Rainfall(mm)

Mean temperaturein the coldestmonth (∘C)

Phases oftrees

Basal area(m2ha)

Shannonindex

DECI(40ndash400m) 1000ndash1500 28

Mature treesSaplingsSeedlings

2332020mdash

279248262

SEMI(400ndash650m)

2500ndash3500 24 Mature treesSaplingsSeedlings

4566089mdash

367315311

EVER(650ndash1200m)

3500ndash5000 22 Mature treesSaplingsSeedlings

4800124mdash

334309349

WOOD(900ndash1400m)

3500ndash5000 25 Mature treesSaplingsSeedlings

06904mdash

221216156

SUBM(1200ndash1800m)

5000ndash6000 13 Mature treesSaplingsSeedlings

3651069mdash

326345351

MONT(1800ndash2450m)

5000ndash6000 9 Mature treesSaplingsSeedlings

3087145mdash

321319271

lowastMature trees (ge30 cm gbh) saplings (ge 10lt 30 cm gbh) and seedlings (lt10 cm gbh)

of trees were in the smallest girth class (Figure 6) In WOODvegetation which was fire affected and grass dominated 96of trees were in the smallest girth class

32 Regeneration Frequencies of regenerating species(saplings + seedlings) were maximal in undisturbed forestcompared to disturbed one (caused by fuel wood collection

and cattle grazing) In DECI of 71 taxa recorded only 26were present in all three growth phases 24 were presentin only one stage and only 10 species were regeneratingwell (seedling gt sapling gt tree) Nevertheless Lagerstroemiamicrocarpa one of the dominant species in DECI hadno seedlings indicative of poor regeneration potential(Tables 1 and 3 see Supplementary Material Appendix 1available online at httpdxdoiorg1011552013890862)

ISRN Ecology 7

Table 3 Distribution pattern of mature and regenerating phases of trees occur in different vegetation types Regenerating species and speciesshare in all phases of trees was lower in disturbed vegetation type such as DECI and WOOD as compared to other vegetation types Percentsimilarity in species composition (using Sorenson index of similarity) of mature trees and regenerating individuals (saplings + seedlings) indifferent vegetation types of the study area and new species recruited (trees devoid of adult stage) are also shown

Vegetationtypes

Tree species occur inlowastRegeneratingspecies ()

Similarity betweenmature trees andregenerating individuals

New entryspecies ()All phases () Mature phase

only ()Regeneratingphase only ()

DECI 26 (37) 21 (30) 12 (17) 50 (70) 69 12 (17)SEMI 53 (41) 11 (9) 27 (21) 116 (91) 82 24 (18)EVER 49 (40) 11 (9) 24 (20) 111 (91) 81 23 (18)WOOD 8 (29) 8 (29) 11 (39) 20 (71) 49 10 (35)SUBM 40 (43) 4 (4) 18 (20) 87 (95) 88 20 (21)MONT 20 (47) 6 (14) 11 (26) 37 (86) 76 10 (23)lowastA number of species occur in saplings andor seedlings and these species may or may not have mature tree stage of species has been given in brackets

132 36

8

485

39

390 85

5

65

250 393

77

215 39

22073 95

57

7717

795

6971 16

395

1

10

100

1000

10000

100000

DECI SEMI EVER WOOD SUBM MONT

Den

sity

Vegetation types

Mature treesSaplingsSeedlings

Figure 4 Densities (no haminus1 in log10scale) of mature trees (ge30 cm

gbh (girth at breast height)) saplings (ge 10 lt 30 cm gbh) and seedl-ings (lt10 cm gbh) in six vegetation types occurring in the WesternGhats LSD post hoc test clarified that density of disturbed forestlike DECI and WOOD was significantly different with undisturbedvegetation type except MONT

In vegetation types influenced by disturbance and firelike WOOD 29 of species were common in all growthphases and seedling richness was very low in these types ofvegetation (Supplementary Material Appendix 2)

In vegetation types at mid elevations namely EVERand SEMI 49ndash53 of species were present in all growthphases 25ndash30 of species occurred in only one phase(Supplementary Material Appendices 3 and 4) In forestsat higher elevations namelySUBM and MONT 43 and47 of species respectively were present in all growthphases In SUBM 25 species had poor regeneration potential(Supplementary Material Appendix 5) In MONT 20 specieswere present in all growth phases and 12 had no regenerationpotential (Table 3 Supplementary Material Appendix 6)

33 Change in Species Composition among Tree Phases Over-all species richness of mature trees was higher than richnessof saplings and seedlings in all vegetation types Among the

dominant species a few trees had exceptionally large num-bers of seedling and saplings Individual trees did notcontribute equally to the seedling population or to laterrecruitment in the sapling stage Density of regeneratingindividuals (saplings + seedlings) was highest in EVER andlowest in WOOD There was significant difference in thedensity of regenerating individuals (seedling + saplings)among different vegetation types (119865

5611= 132 119875 lt 0001)

Also there was significant difference in the density of matureand regenerating phase among all vegetation types exceptWOOD (DECI 119865

1130= 117 119875 lt 0001 SEMI 119865

1269= 37

119875 lt 005 EVER 1198651255= 73 119875 lt 0008 WOOD 119865

141= 34

119875 lt 0059 SUBM 1198651201= 101 119875 lt 0002 MONT 119865

188=

51 119875 lt 0026)The overall changes in species composition from mature

stage to regenerating stage (sapling + seedling phases) ofdifferent vegetation types 21 that is 79 similarity (usingSorenson index of similarity) between mature and regenerat-ing phase In disturbed WOOD and DECI the similarity inspecies composition between mature trees and regeneratingindividuals was 49 and 69 respectively In little-disturbedvegetation types species similarity between mature trees andregenerating phases was relatively high In all the forest typesnew entry species (tree species with no adult stages) werepresent Percent of new entry species was highest in fireaffected WOOD vegetation (Table 3)

4 Discussion

41 Species Diversity Theuse of species-individuals curves inaddition to species-area curves provides a clear insight intospecies diversity More sampling area is required for speciesrich vegetation type compared to species poor one and ingeneral the minimum area varies with number of speciesfrom one vegetation type to another [51] In our data species-rich communities like SEMI and EVER seem to have lessdominance than species-poor communities However lowerrarefaction curve in MONT suggests that abundance effectmay not be the sole reason for high richness The accumu-lation of new species with increasing sampling effort canbe visualized with a species accumulation curve Increasing

8 ISRN Ecology

0

20

40

60

80

100

Frequency classes

DECI

0ndash20 21ndash40 41ndash60 61ndash80 81ndash100

Spec

ies (

)

(a)

0

20

40

60

80

100SEMI

Frequency classes0ndash20 21ndash40 41ndash60 61ndash80 81ndash100

Spec

ies (

)

(b)

0

20

40

60

80

100

EVER

Frequency classes0ndash20 21ndash40 41ndash60 61ndash80 81ndash100

Spec

ies (

)

(c)

0

20

40

60

80

100

WOOD

Frequency classes0ndash20 21ndash40 41ndash60 61ndash80 81ndash100

Spec

ies (

)

(d)

0

20

40

60

80

100

SUBM

Frequency classes0ndash20 21ndash40 41ndash60 61ndash80 81ndash100

Mature treesSaplingsSeedlings

Spec

ies (

)

(e)

0

20

40

60

80

100

MONT

Mature treesSaplingsSeedlings

Frequency classes0ndash20 21ndash40 41ndash60 61ndash80 81ndash100

Spec

ies (

)

(f)

Figure 5 Percent frequencies of trees (ge30 cm gbh) in different vegetation types Most of the species were in the lowest frequency class inall vegetation types other than MONT indicating that a few species were widely distributed most were restricted in distribution This is atypical species-abundance distribution (normal distribution) and the tree species in all the vegetation type were heterogeneous distributionin Raunkiaerrsquos sense

the area sampled increases observed species richness bothbecause more individuals get included in the sample andbecause large areas are environmentally more heterogeneousthan small areas [52] The correlation between species rich-ness and abundance suggests that process affecting change ineither richness or abundance also affects species diversity

Species richness of DECI was reduced likely due to lowrainfall and anthropogenic disturbances such as firewoodcollection and cattle grazing In fire affected WOOD grasseswere the dominant life forms these were intermingled with afew fire tolerant light demanding trees High species richnessof trees in SEMI EVER and SUBM was probably relatedto high rainfall and optimal climatic conditions (Table 2)Low temperature and high wind velocity in the MONT may

negatively impact tree growth and reduce species richnessthere DECI standswere dominated bymembers of the familyFabaceae while Euphorbiaceae and Rubiaceae dominated inEVER at mid elevations High elevation SUBM and MONTwere dominated bymembers of the Lauraceae andMyrtaceaewhich have volatile oils in their tissues that resist freezingdamage in plant cells [53]

Compared to DECI tree species diversity was very highin other forest types at higher elevations other than in thefire-affected WOOD High species diversity of SEMI is dueits transitional nature that is this vegetation type is ecotonearea suitable for both deciduous and evergreen tree species sothere is an increase in the number of species Species diversityindices for saplings were lower than those for mature trees

ISRN Ecology 9

3721 19 10 6 3 2 1 1

020406080

100DECI

Tree

s (

)

Girth classes

10ndash5

0

101ndash

150

151ndash

200

201ndash

250

251ndash

300

301ndash

350

351ndash

400

51ndash1

00

gt400

(a)

020406080

10060

20 9 3 2 2 21 1

SEMI

Tree

s (

)

Girth classes

10ndash5

0

101ndash

150

151ndash

200

201ndash

250

251ndash

300

301ndash

350

351ndash

400

51ndash1

00

gt400

(b)

020406080

10065

19 9 3 2 2 21 1

EVER

Tree

s (

)

Girth classes

10ndash5

0

101ndash

150

151ndash

200

201ndash

250

251ndash

300

301ndash

350

351ndash

400

51ndash1

00

gt400

(c)

020406080

100 96

4 0 0 0 0 0 0 0

WOOD

Tree

s (

)

Girth classes

10ndash5

0

101ndash

150

151ndash

200

201ndash

250

251ndash

300

301ndash

350

351ndash

400

51ndash1

00

gt400

(d)

020406080

10058

20 12 4 2 1 1 1 1

SUBM

Girth classes

10ndash5

0

101ndash

150

151ndash

200

201ndash

250

251ndash

300

301ndash

350

351ndash

400

Tree

s (

)

51ndash1

00

gt400

(e)

020406080

10070

243 2 1 0 0 0 0

MONT

Tree

s (

)

Girth classes

10ndash5

0

101ndash

150

151ndash

200

201ndash

250

251ndash

300

301ndash

350

351ndash

400

51ndash1

00

gt400

(f)

Figure 6 Girth frequency distributions of trees in different vegetation types of the study area Girth-size was highest in SEMI and EVER Ahigh percentage of lower girth class trees in DECI results from reduced fuel wood extraction by people of nearby areas The reverse J-shapedgbh distribution of trees indicates evolving or expanding population

and seedlings in DECI is due to overharvesting of saplingsfor firewood The lowest species diversity value in WOODindicates low species richness and dominance of one or twospecies in the tree community In the present study Shannonindex values for tree species are similar to values for othertropical forests of the world (Table 4) However detailedcomparisons with other studies are inadvisable because oflarge differences in sample size standard girth parametersand environmental conditions

Density and frequency distributions of trees contributeto the structure of tropical forests Tree density in DECI wasmuch lower than that of other forest types perhaps due to lowrainfall and anthropogenic disturbances Density was least inthe fire-affected WOOD Sapling densities were elevated inSEMI and EVER Late secondary successional species werewell represented in the sapling population of EVER whichmay be indicative of recent natural disturbances in this foresttype that promoted regeneration of late secondary speciesMONT had high sapling density due to the stunted nature oftrees caused by very low temperature and high wind velocityprevalent there [54]

Densities of trees in the study area were similar toestimates from tropical forests within India and other tropicalregions (Table 4) In tropical forests outside India there ismuch variation in the densities of trees gt30 cm gbh (98ndash1930 trees haminus1) especially in Amazonian forests In theNeotropics maximum species richness of tree individualsgt10 cm gbh reaches 300 haminus1 [55] In South-East Asia thehighest richness is 225 haminus1 [56]

In the present studymost of the species were in frequencyclass 0ndash20 and fewest were in frequency class 80ndash100The frequency distribution of tree species suggested thatmostof them had low frequency as would be expected in typicalspecies-abundance distribution A plant species should beconsidered homogeneously distributed when the numbersof individuals are the same in all parts of a community[50] Hence tree species in all the vegetation types of thestudy area were heterogeneously distributed Girth classfrequency distributions of most species in vegetation typeswe studied fit ldquoreverse Jrdquo-shaped patterns with most trees insmaller girth classes and few old trees Vegetation types otherthan WOOD fit negative exponential patterns indicative of

10 ISRN Ecology

Table4Ve

getatio

nparameterso

fforestcom

mun

ities

inthetropics

ofIndiaa

ndotherc

ountrie

s

Foresttypes

Locatio

nPlot

size(ha)

Tree

girth

studied

(cm)

Tree

density

(noha)

Tree

basal

area

(m2 ha)

Shanno

nindex

References

Presentstudy

DEC

IWestern

Ghats(N

BR)

4ha

ge30

cm132

234

279

Present

study

SEMI

ldquo4ha

ge30

cm368

457

367

ldquo

EVER

ldquo4ha

ge30

cm485

480

334

ldquo

WOOD

ldquo3ha

ge30

cm39

069

221

ldquo

SUBM

ldquo4ha

ge30

cm390

365

326

ldquo

MONT

ldquo4ha

ge30

cm855

309

321

ldquo

India

Evergreenforests

Silent

valleyWestern

Ghat

mdashge315

620ndash

709

29ndash103

mdash[6]

Moistdecidu

ousforests

Pepp

araWGhats

mdashge30

590ndash

740

13ndash51

2ndash33

[7]

Moistdecidu

ousforests

Chim

mon

yWestern

Ghats

mdashge30

558

3719

ndash24

[8]

Semievergreen

forests

Pepp

araWestern

Ghats

mdashge30

670ndash

940

45ndash6

229

[7]

Semievergreen

forests

Chim

mon

yWestern

Ghats

mdashge30

728

4727ndash32

[8]

Scrubjung

leto

wetevergreenforests

Kalakk

adRF

Western

Ghats

02

gt20

320ndash

1260

18ndash107

mdash[9]

Evergreenforests

Karnataka

044

mdash44

6ndash1386

33ndash4

8mdash

[10]

Evergreenforests

Pepp

ara

mdashge30

860ndash

1370

7633

[7]

Evergreenforests

NelliampathiWestern

Ghats

mdashge30

mdash498

3ndash37

[11]

Dry

tropicalforests

Vind

hyar

egion

mdashgt30

294ndash

559

7ndash23

mdash[12]

Dry

evergreenforests

Puthup

etSacred

GroveC

orom

andel

coast

02

gt20

280

11mdash

[13]

Trop

icalwe

tevergreen

forests

Kalakk

ad-M

undanthu

raiT

iger

Reserve

Western

Ghats

050

gt30

315ndash418

54ndash8

4mdash

[14]

Trop

icalwe

tevergreen

forests

KodayarWestern

Ghats

050

gt30

352ndash117

328ndash81

mdash[15]

Subtropicalh

illforests

Pepp

araWestern

Ghats

mdashge30

1580ndash1930

27ndash34

27

[7]

Mon

tane

temperateforests

Mannavanshola

mdashge30

566

52399

[16]

ISRN Ecology 11

Table4Con

tinued

Foresttypes

Locatio

nPlot

size(ha)

Tree

girth

studied

(cm)

Tree

density

(noha)

Tree

basal

area

(m2 ha)

Shanno

nindex

References

Other

coun

tries

Trop

icalrain

forests

(you

ngforests

)Ba

rrow

ColoradoIsland

Panam

a5

gt18

84ndash171

26ndash

52

mdash[17]

Trop

icalrain

forests

(old

forests

)Ba

rrow

ColoradoIsland

Panam

a50

gt18

143ndash177

43ndash5

mdash[18]

Trop

icalrain

forests

Amazon

ia3

314

1420

28ndash6

8mdash

[19]

Equatoria

linsular

forests

Easte

rnCa

rolline

Island

Panam

a50

gt314

98ndash114

17mdash

[20]

Trop

icalrain

forests

Jung

kaRe

serveMalaysia

1191

104

23mdash

[21]

Trop

icalrain

forests

Gun

ungSilamM

alaysia

004

314

513ndash1596

23ndash4

6mdash

[22]

Trop

icalmoistforests

Sing

apore

04

gt63

604

mdashmdash

[23]

Trop

icalrain

forests

Valcan

BarvaCostaRica

6gt314

391ndash617

mdashmdash

[24]

Slop

eforests

New

Caledo

nia

28

gt314

1533

49mdash

[25]

Allu

vium

forests

New

Caledo

nia

26

gt314

1183

47mdash

[25]

Equatoria

lforests

KongoIsland

mdashmdash

440ndash

553

10ndash4

5mdash

[26]

Trop

icalrain

forests

Amazon

ia3

gt314

1720

78mdash

[19]

Trop

icalseason

alrain

forests

Xishuang

bann

aCh

ina

2500

m2

15154

mdash34

[27]

Trop

icalmon

tane

rain

forests

Xishuang

bann

aCh

ina

1600

m2

15123

mdash32

[27]

Evergreenbroadleaved

forests

Xishuang

bann

aCh

ina

1200

m2

15165

mdash25

[27]

Mon

soon

forests

Xishuang

bann

aCh

ina

400m

210

150

mdash16

[27]

ldquoStudy

cond

uctedin

6different

vegetatio

ntypeso

fWestern

Ghats(N

BR)

12 ISRN Ecology

relatively undisturbed or less disturbed conditions in thestands The high annual precipitation rate and optimumtemperature of EVER may have contributed to high treegrowth rate and higher tree basal area

42 Regeneration All other vegetation types had betterregeneration than DECI In WOOD the transition rate ofstems from small girth classes to larger girth classes was lowPoor tree regeneration in DECI and WOOD can probablybe attributed to fuel wood collection frequent fires andgrazing by cattle In all forest types 29ndash47 of tree specieswere present in all three growth phases other species werepresent in either one or two growth phases Dominant speciesoccurred in all girth classes of vegetation types other thanWOOD in whichmost trees were in the smaller girth classesThere were more large trees in vegetation types like SEMIand EVER and in these sapling and seedling densities wereadequate for restocking the complement of canopy trees

Change in species composition across mature and regen-erating tree phases was more frequent in disturbed foresttypes like DECI and WOOD In some cases the dominantspecies in adult and seedling stages were quite differentin these two disturbed forest types Our results are notcongruent with observationsmade in northeastern India [39]where tree seedling survival rate increases with increasingforest disturbance We found species without regeneratingphases these are unlikely to persist Others that occurred onlyin seedling and sapling stages were new entrants to the forestspecies complement These are examples of discontinuouspopulation structures Such structures occur in a number ofother tropical countries [57ndash59] The dominant species in aforest stand is generally present in all size classes [38] Thesize class structures of trees indicate the probability of speciespersistence into the future this information is very valuablein the design of management strategies aiming to improvestand structure and species diversity Changes in speciescomposition and recruitment of new species in differentvegetation types are indicative of future species compositionin changing environments

5 Conclusions

The species diversity of trees varied across vegetation types inthe Western Ghats landscape Rarefaction curves show thatspecies diversity is highest in SEMI and EVER and lowest inWOOD while species abundance is highest in MONT Vege-tation types of study area are in heterogeneous in distributionThere were large differences in species composition of adulttrees and regenerating individuals in the disturbed vegetationtypes as compared to undisturbed stands The present studyreveals that the anthropogenic disturbance causes disruptionof forest structure and change in species composition whichultimately leads to reduction of tree species richness andabundance which are the major attributes of forests Newrecruits were found in all vegetation types indicating thattheywere not headed to extinction however disturbed standsmay move to new species compositions in the future

Acknowledgments

The authors are thankful to the Ministry of Environmentand Forests for financial support and the Vice Chancellorof University of Delhi and the Director of Kerala ForestResearch Institute for facilities provided The first authorwould like to thank Professor C R Babu for facilities andencouragement The authors are very much obliged to allmembers of the Cholanaikkan tribe who helped duringthe field survey The Kerala Forest Department provided alllogistical support for the floristic and ecological survey of theforest area (trees haminus1) in three different growth phases of sixvegetation

References

[1] M A Huston Biological Diversity The Coexistence of Species inChanging Landscapes Cambridge University Press CambridgeUK 1994

[2] T C Whitmore An Introduction to Tropical Rain ForestsOxfordUniversity Press NewYork NYUSA 2nd edition 1998

[3] M L Khan S Menon and K S Bawa ldquoEffectiveness of theprotected area network in biodiversity conservation a case-study of Meghalaya staterdquo Biodiversity and Conservation vol 6no 6 pp 853ndash868 1997

[4] C M Pringle ldquoNutrient spatial heterogeneity effects on com-munity structure physiognomy and diversity of stream algaerdquoEcology vol 71 no 3 pp 905ndash920 1990

[5] M Parviainen M Marmion M Luoto W Thuiller and RK Heikkinen ldquoUsing summed individual species models andstate-of-the-art modelling techniques to identify threatenedplant species hotspotsrdquo Biological Conservation vol 142 no 11pp 2501ndash2509 2009

[6] J S Singh S P Singh A K Saxena and Y S Ravat ldquoThe forestvegetation of Silent Valleyrdquo in Tropical Rain Forests The LeedsSymposium pp 25ndash52 1984

[7] A O Varghese ldquoAssessment of biodiversity of PepparaWildlifeSanctuary Trivandrum District Keralardquo Journal of Economicand Taxonomic Botany vol 23 pp 117ndash127 1998

[8] M A Suraj Phytosociological and vagetation mapping at chim-mony wildlife Sanctuary (Kerala) using remote sensing technique[PhD thesis] FRI University Dehradun India 1997

[9] N Parthasarathy Studies on the vacular flora structure andnutrient cycling in Kalakad Reserve Forest Western Ghats TamilNadu [PhD thesis] University of Madras Tamil Nadu India1986

[10] S N Rai and J Proctor ldquoEcological studies on four rainforests in Karnataka India environment forest structure andvegetationrdquo Journal of Vegetation Science vol 1 pp 609ndash6141986

[11] U M Chadrashekara A R R Menon K K N Nair NSasidharan and K Swarupanandan ldquoEvaluating plant diversityin different forest types of Kerala by laying out permanent sam-ple plotsrdquo KFRI Research Report 156 Kerala Forest ResearchInstitute Peechi India 1998

[12] C S Jha and J S Singh ldquoComposition and dynamics of drytropical Forest in relation to soil texturerdquo Journal of VegetationScience vol 1 no 5 pp 609ndash614 1990

[13] NVisalakshi ldquoVegetation analysis of two tropical dry evergreenforests in southern IndiardquoTropical Ecology vol 36 no 1 pp 117ndash127 1995

ISRN Ecology 13

[14] T Ganesh R Ganesan M Soubadra Devy P Davidar and K SBawa ldquoAssessment of plant biodiversity at amid-elevation ever-green forest of Kalakad-Mundanthurai Tiger Reserve WesternGhats Indiardquo Current Science vol 71 no 5 pp 379ndash392 1996

[15] S M Sundarapandian and P S Swamy ldquoForest ecosystemstructure and composition along an altitudinal gradient in theWestern Ghats South Indiardquo Journal of Tropical Forest Sciencevol 12 no 1 pp 104ndash123 2000

[16] K Swarupanandan N Sasidharan K C Chacko and SChanduBasha ldquoFloristic and ecological studies on the Sholasof Idukki Districtrdquo in Shola Forests of Kerala Environmentand Biodiverstiy K K N Nair S K Khanduri and K Bala-subramaniayan Eds pp 259ndash286 Kerala Forest DeparmentThiruvanathapuram Kerala Forest Research Institute PeechiIndia 2001

[17] R W Thorington S Tannenbaum A Tarak and R RudranldquoDistribution of trees in Baro Colorado Islands a hectaresamplerdquo in The Ecology of a Tropical Forest-Seasonal Rhythmsand Long-term Changes E G Leigh Jr A S Rand and D MWindsor Eds Smithsonian Institute Press Washington DCUSA 1982

[18] S P Hubbell and R B Foster ldquoDiversity of canopy speciesin a neotropical forest and implications for conservationrdquo inTropical Rain Forest Ecology and Management S L Sutton TCWhitmore andA C Chadwick Eds Blackwell Oxford UK1983

[19] D G Campbell D C Daly G T Prance and U N MacielldquoQuantitative ecological inventory of terra firme and varzeatropical forest on the Rio Xingu Brazilian Amazonrdquo Brittoniavol 38 no 4 pp 369ndash393 1986

[20] S Itow ldquoSpecies diversity of equatorial insular forests on Ponapeand Kosrae Micronesiardquo Ecological Research vol 1 no 2 pp223ndash227 1986

[21] C C Ho D M Newbery and M E D Poore ldquoForestcomposition and inferred dynamics in Jengka Forest ReserveMalaysiardquo Journal of Tropical Ecology vol 3 no 1 pp 25ndash561987

[22] J Proctor Y F Lee A M Langley W R C Munro and TNelson ldquoEcological studies onGunung Silam a small ultrabasicmountain Sabah Malaysiardquo Journal of Ecology vol 74 pp 455ndash463 1988

[23] F R Swan Jr ldquoTree distribution patterns in the Bukittimahnature reserve Singaporerdquo Gardens Bulletin vol 41 pp 59ndash811988

[24] A Heaney and J Proctor ldquoPreliminary studies on foreststructure and floristics on Volcan Barva Costa Ricardquo Journalof Tropical Ecology vol 6 no 3 pp 307ndash320 1990

[25] T Jaffre and J M Veillon ldquoEtude floristique et structuralede deux forets denses humides sur roches ultrabasiques enNouvelle- Caledonierdquo Bulletin du Museum National drsquoHistoireNaturelle vol 12 pp 243ndash273 1990

[26] MMosango ldquoContribution ldquoA lrsquoetude botanic biogeo 1rdquo ecosys-tem Foret en region equatorial (Ile KongoloZaire)rdquo BelgiumJournal of Botany vol 124 pp 167ndash194 1991

[27] M Cao and J Zhang ldquoTree species diversity of tropical forestvegetation in Xishuangbanna SW Chinardquo Biodiversity andConservation vol 6 no 7 pp 995ndash1006 1997

[28] C S Jha L Goparaju A Tripathi B Gharai A S Raghubanshiand J S Singh ldquoForest fragmentation and its impact onspecies diversity an analysis using remote sensing and GISrdquoBiodiversity and Conservation vol 14 no 7 pp 1681ndash1698 2005

[29] P S Roy C B S Dutt and P K Joshi ldquoTropical forest resourceassessment and monitoringrdquo Tropical Ecology vol 43 no 1 pp21ndash37 2002

[30] R Sagar A S Raghubanshi and J S Singh ldquoAsymptoticmodelsof species-area curve for measuring diversity of dry tropicalforest tree speciesrdquo Current Science vol 84 no 12 pp 1555ndash1560 2003

[31] R Sukumar H S Dattaraja H S Suresh et al ldquoLong-termmonitoring of vegetation in a tropical deciduous forest inMudumalai southern Indiardquo Current Science vol 62 pp 608ndash616 1992

[32] UMChandrashekara and P S Ramakrishnan ldquoVegetation andgap dynamics of a tropical wet evergreen forest in the WesternGhats of Kerala Indiardquo Journal of Tropical Ecology vol 10 no3 pp 337ndash354 1994

[33] T Ganesh R Ganesan M Soubadra Devy P Davidar and K SBawa ldquoAssessment of plant biodiversity at amid-elevation ever-green forest of Kalakad-Mundanthurai Tiger Reserve WesternGhats Indiardquo Current Science vol 71 no 5 pp 379ndash392 1996

[34] J P Pascal and R Pelissier ldquoStructure and floristic compositionof a tropical evergreen forest in south-west Indiardquo Journal ofTropical Ecology vol 12 no 2 pp 191ndash210 1996

[35] N Ayyappan and N Parthasarathy ldquoBiodiversity inventory oftrees in a large-scale permanent plot of tropical evergreen forestat Varagalaiar Anamalais Western Ghats Indiardquo Biodiversityand Conservation vol 8 no 11 pp 1533ndash1554 1999

[36] A Kumar B G Marcot and A Saxena ldquoTree species diversityand distribution patterns in tropical forests of Garo HillsrdquoCurrent Science vol 91 no 10 pp 1370ndash1381 2006

[37] N Parthasarathy ldquoTree diversity and distribution in undis-turbed and human-impacted sites of tropical wet evergreenforest in southern Western Ghats Indiardquo Biodiversity andConservation vol 8 no 10 pp 1365ndash1381 1999

[38] M L Khan J P N Rai and R S Tripathi ldquoPopulation structureof some tree species in disturbed and protected subtropicalforests of north-east Indiardquo Acta Oecologica vol 8 no 3 pp247ndash255 1987

[39] R S Tripathi and M L Khan ldquoRegeneration pattern andpopulation structure of trees in subtropical forest of North EastIndiardquo in Tropical Ecosystem-Ecology and Management K PSingh and J S Singh Eds pp 431ndash441 Wiley Eastern LimitedNew Delhi India 1992

[40] A E Scholl and A H Taylor ldquoRegeneration patterns in old-growth red fir-western white pine forests in the northern SierraNevada Lake Tahoe USArdquo Forest Ecology and Managementvol 235 no 1ndash3 pp 143ndash154 2006

[41] D A Clark ldquoRegeneration of canopy trees in tropical wetforestsrdquo Trends in Ecology and Evolution vol 1 no 6 pp 150ndash154 1986

[42] P C J Barker and J B Kirkpatrick ldquoPhyllocladus aspleniifoliusvariability in the population structure the regeneration nicheand dispersion patterns in Tasmanian forestsrdquo Australian Jour-nal of Botany vol 42 no 2 pp 163ndash190 1994

[43] C K Augspurger ldquoSeedling survival of tropical tree speciesinteractions of dispersal distance light-gaps and pathogensrdquoEcology vol 65 no 6 pp 1705ndash1712 1984

[44] O L Phillips ldquoLong-term environmental change in tropicalforests increasing tree turnoverrdquo Environmental Conservationvol 23 no 3 pp 235ndash248 1996

[45] Ministry of Environment and Forests ldquoPlant discoveries 2011newgenera species andnew recordsrdquo Botanical Survey of IndiaMinistry of Environment and Forests New Delhi India 2012

14 ISRN Ecology

[46] ldquoWeblink 2007rdquo httpwwwbiodiversityhotspotsorgxphot-spotshotspots by region

[47] D Mueller-Dombois and H Ellenberg Aims and Methods ofPlant Ecology John Wiley amp Sons New York NY USA 1974

[48] K K N Nair and R Jayakumar ldquoPhytogeography endemismand affinities of the flora of NewAmarambalamReserve Forestsin theWesternGhats of Indiardquo Indian Journal of Forestry vol 31pp 85ndash94 2008

[49] A E Magurran Ecological Diversity and Its MeasurementCroom Helm Ltd London UK 1988

[50] C Raunkiaer The Life Forms of Plants and Statistical PlantGeography Clarendon Press Oxford UK 1934

[51] B Rice andMWestoby ldquoPlant species richness at the 01 hectarescale in Australian vegetation compared to other continentsrdquoVegetatio vol 52 no 3 pp 129ndash140 1983

[52] SM Scheiner ldquoSix types of species-area curvesrdquoGlobal Ecologyand Biogeography vol 12 no 6 pp 441ndash447 2003

[53] H G Jones Plants and Microclimate Cambridge UniversityPress Cambridge UK 1983

[54] N C Nair The Southern Western Ghats A Biodiversity Con-servation Plan Indian National Trust for Arts and CulturalHeritage New Delhi India 1991

[55] AHGentry ldquoChanges in plant community diversity and floris-tic composition on environmental and geographical gradientrdquoAnnals of the Missouri Botanical Garden vol 75 no 1 pp 1ndash341988

[56] T CWhitmore Tropical Rain Forests of the Far East ClarendonPress Oxford UK 1984

[57] N V L Brokaw ldquoGap-phase regeneration of three pioneer treespecies in a tropical forestrdquo Journal of Ecology vol 75 no 1 pp9ndash19 1987

[58] S Itow and D Mueller-Dombois ldquoPopulation structure stand-level dieback and recovery of Scalesia pedunculata forest in theGalapagos Islandsrdquo Ecological Research vol 3 no 3 pp 333ndash339 1988

[59] T CWhitmore ldquoA review of some aspects of tropical rainforestseedling ecology with suggestions for further enquiryrdquo inEcology of Tropical Forest Tree Seedlings M D Swaine Ed pp3ndash39 UNESCOParthenon Paris France 1996

Submit your manuscripts athttpwwwhindawicom

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Marine BiologyJournal of

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Applied ampEnvironmentalSoil Science

Volume 2014

Advances in

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Environmental Chemistry

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International Journal of

Geophysics

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EarthquakesJournal of

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ScientificaHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

OceanographyInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014

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Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

ClimatologyJournal of

Page 5: Research Article Species Diversity and Tree Regeneration ...downloads.hindawi.com/archive/2013/890862.pdf · Species Diversity and Tree Regeneration Patterns in Tropical Forests of

ISRN Ecology 5

58

100 98

17

75

3241

9181

17

64

3133

83 78

9

65

27

71

127 122

28

92

43

0

20

40

60

80

100

120

140

DECI SEMI EVER WOOD SUBM MONT

Num

ber o

f spe

cies

Vegetation types

Mature treesSaplings

SeedlingsTotal species

Figure 2 Species richness (number of species) by tree growth phase in six vegetation types occurring in the Western Ghats Multiplecomparison LSD post hoc test showed richness of all the vegetation types was significantly different (119875 lt 001ndash005) See Table 1 for anexplanation of vegetation type abbreviations

25 Statistical Analysis One-way ANOVA was used to testdifferences of density (ge30 cm gbh) overall species rich-ness and basal area among vegetation types LSD post hoctests were used to detect significant pair wise differencesamong means of dependent variables One-way analysisof covariance (ANCOVA) was conducted to test of thecovariate (abundance) is that it evaluates the relationshipbetween the covariate (abundance) and the dependant vari-able (species richness) controlling for the factor (vegetationtypes) Pearson correlation coefficients were calculated todetect significant correlations among vegetation parametersespecially cumulative species richness and abundance of eachvegetation typeWe used the statistical package SPSS (Version16 www-01ibmcomsoftwareanalyticsspss) for all testsFor rarefaction we used statistical software Biodiversity Pro(httpwwwsmiacukpeter-lamontbiodiversity-pro)

3 Results

31 Species Diversity In the six vegetation types sampled inthe study area there were 257 tree species belonging to 62families and 147 genera of angiosperms Richness of treespecies (Figure 2) was highest in SEMI (127 spp) and lowestin theWOOD (28 spp) Species-area and species-individualsaccumulation curve (rarefaction curve) against equal-sizedsampling areas in different vegetation types showed a distinctdifference in the richness and abundance Rarefaction canbe used to examine the evenness of the distribution ofspecies in assemblages by comparing steepness of curvesSteeper rarefaction curves indicate high heterogeneity Onestriking results of rarefaction curves was that SEMI andEVER have the highest curves This means that speciesdiversity per equal-sized area was highest in these vegetationtypes but MONT has the most individuals per unit areaVegetation type at other extreme (low species richness) wasWOOD and MONT (Figure 3) The overall difference inspecies richness among six vegetation types was statisticallysignificant (119865

5179= 651 119875 lt 00001) Species richness

and corresponding abundance were significantly positivelycorrelated in all the vegetation types (DECI 119903 = 098 119875 lt00001) SEMI 119903 = 095 119875 lt 00001 EVER 119903 = 094 119875 lt00001 WOOD 119903 = 077 119875 lt 00001 SUBM 119903 = 095 119875 lt00001 MONT 119903 = 087 119875 lt 00001) A primary analysisevaluating the homogeneity-of-regression (slopes) assump-tion indicated that the relationship between the covariate(abundance) and the dependant variable (species richness)differs significantly as a function of the independent variable(vegetation types) (1198772 = 0152 ANCOVA 119865

6179= 1334

119875 lt 0001) A significant interaction between the covariateand the factor suggests that the differences on the dependentvariable among groups vary as a function of the covariateSince the result from the ANCOVA was significant it is notmeaningful to proceed further The highest Shannon indexvalue occurred in SEMI (367 for plants with gbh ge 30 cm)and lowest value reported in WOOD (Table 2)

Dominant tree species in mature and sapling stages weremore or less similar in most vegetation types but dominantspecies in the seedling stage varied considerably (Table 1)Overall stand density of mature trees (ge30 cm gbh) washighest in MONT (855 trees haminus1) and lowest in WOOD(39 trees haminus1) Densities of both tree saplings and seedlingswere highest in EVER (Figure 4) Among 25 tree speciesdominant across the different forest types 16 dominated inthe tree phase 15 in the sapling phase and 14 in the seedlingphase Among the different forest types therewere significantdifference in tree (ge30 cm gbh) density (119875 lt 00001 119865

5389=

269) and basal area (119875 lt 0007 1198655389= 33) Mean basal

area of trees was highest in EVER (48m2 haminus1) and lowest inWOOD (Table 2)

Raunkiaerrsquos frequency analyses revealed that most ofthe tree species were rare as in the case for other tropicalforests In all forest types 60ndash95 of tree species werein the lowest frequency class (Figure 5) Furthermore therewere few individuals in the 80ndash100 frequency class Inforest types other than DECI 58ndash70 of trees were in thesmallest girth category (gbh 50ndash100 cm) in DECI only 37

6 ISRN Ecology

DECISEMIEVER

WOODSUBMMONT

120

100

80

60

40

20

0

Spec

ies

0 05 1 15 2 25Area (ha)

(a)

0

20

40

60

80

100

120

140

0 200 400 600 800 1000 1200 1400 1600 1800

Spec

ies

Individuals

DECISEMIEVER

WOODSUBMMONT

(b)

Figure 3 Species accumulation and rarefaction curves of different vegetation types Curves were created random series of 30 plots of 009 ha(ie 27 ha for each vegetation type) (a) Species-area curves (sample-based rarefaction) and (b) species-individuals curve (individuals-basedrarefaction) Looking at the individual-based rarefaction curve all four vegetation types seem to be quite similar in species richness exceptMONT which is drastically lower although containing the highest number of individuals WOOD which contain too few individuals toproduce a comparable result The sample-based rarefaction on the other hand identifies SEMI and EVER as the two most species richcommunities differing from the rest Rarefaction curves for six vegetation types predict the rate of accumulation of species with increasingnumber of individuals (abundance) See Table 1 for an explanation of vegetation type abbreviations

Table 2 Vegetation parameters calculated for three tree phases in different vegetation types See Table 1 for explanation of vegetation typeabbreviations

Vegetation types(Altitude range)

Rainfall(mm)

Mean temperaturein the coldestmonth (∘C)

Phases oftrees

Basal area(m2ha)

Shannonindex

DECI(40ndash400m) 1000ndash1500 28

Mature treesSaplingsSeedlings

2332020mdash

279248262

SEMI(400ndash650m)

2500ndash3500 24 Mature treesSaplingsSeedlings

4566089mdash

367315311

EVER(650ndash1200m)

3500ndash5000 22 Mature treesSaplingsSeedlings

4800124mdash

334309349

WOOD(900ndash1400m)

3500ndash5000 25 Mature treesSaplingsSeedlings

06904mdash

221216156

SUBM(1200ndash1800m)

5000ndash6000 13 Mature treesSaplingsSeedlings

3651069mdash

326345351

MONT(1800ndash2450m)

5000ndash6000 9 Mature treesSaplingsSeedlings

3087145mdash

321319271

lowastMature trees (ge30 cm gbh) saplings (ge 10lt 30 cm gbh) and seedlings (lt10 cm gbh)

of trees were in the smallest girth class (Figure 6) In WOODvegetation which was fire affected and grass dominated 96of trees were in the smallest girth class

32 Regeneration Frequencies of regenerating species(saplings + seedlings) were maximal in undisturbed forestcompared to disturbed one (caused by fuel wood collection

and cattle grazing) In DECI of 71 taxa recorded only 26were present in all three growth phases 24 were presentin only one stage and only 10 species were regeneratingwell (seedling gt sapling gt tree) Nevertheless Lagerstroemiamicrocarpa one of the dominant species in DECI hadno seedlings indicative of poor regeneration potential(Tables 1 and 3 see Supplementary Material Appendix 1available online at httpdxdoiorg1011552013890862)

ISRN Ecology 7

Table 3 Distribution pattern of mature and regenerating phases of trees occur in different vegetation types Regenerating species and speciesshare in all phases of trees was lower in disturbed vegetation type such as DECI and WOOD as compared to other vegetation types Percentsimilarity in species composition (using Sorenson index of similarity) of mature trees and regenerating individuals (saplings + seedlings) indifferent vegetation types of the study area and new species recruited (trees devoid of adult stage) are also shown

Vegetationtypes

Tree species occur inlowastRegeneratingspecies ()

Similarity betweenmature trees andregenerating individuals

New entryspecies ()All phases () Mature phase

only ()Regeneratingphase only ()

DECI 26 (37) 21 (30) 12 (17) 50 (70) 69 12 (17)SEMI 53 (41) 11 (9) 27 (21) 116 (91) 82 24 (18)EVER 49 (40) 11 (9) 24 (20) 111 (91) 81 23 (18)WOOD 8 (29) 8 (29) 11 (39) 20 (71) 49 10 (35)SUBM 40 (43) 4 (4) 18 (20) 87 (95) 88 20 (21)MONT 20 (47) 6 (14) 11 (26) 37 (86) 76 10 (23)lowastA number of species occur in saplings andor seedlings and these species may or may not have mature tree stage of species has been given in brackets

132 36

8

485

39

390 85

5

65

250 393

77

215 39

22073 95

57

7717

795

6971 16

395

1

10

100

1000

10000

100000

DECI SEMI EVER WOOD SUBM MONT

Den

sity

Vegetation types

Mature treesSaplingsSeedlings

Figure 4 Densities (no haminus1 in log10scale) of mature trees (ge30 cm

gbh (girth at breast height)) saplings (ge 10 lt 30 cm gbh) and seedl-ings (lt10 cm gbh) in six vegetation types occurring in the WesternGhats LSD post hoc test clarified that density of disturbed forestlike DECI and WOOD was significantly different with undisturbedvegetation type except MONT

In vegetation types influenced by disturbance and firelike WOOD 29 of species were common in all growthphases and seedling richness was very low in these types ofvegetation (Supplementary Material Appendix 2)

In vegetation types at mid elevations namely EVERand SEMI 49ndash53 of species were present in all growthphases 25ndash30 of species occurred in only one phase(Supplementary Material Appendices 3 and 4) In forestsat higher elevations namelySUBM and MONT 43 and47 of species respectively were present in all growthphases In SUBM 25 species had poor regeneration potential(Supplementary Material Appendix 5) In MONT 20 specieswere present in all growth phases and 12 had no regenerationpotential (Table 3 Supplementary Material Appendix 6)

33 Change in Species Composition among Tree Phases Over-all species richness of mature trees was higher than richnessof saplings and seedlings in all vegetation types Among the

dominant species a few trees had exceptionally large num-bers of seedling and saplings Individual trees did notcontribute equally to the seedling population or to laterrecruitment in the sapling stage Density of regeneratingindividuals (saplings + seedlings) was highest in EVER andlowest in WOOD There was significant difference in thedensity of regenerating individuals (seedling + saplings)among different vegetation types (119865

5611= 132 119875 lt 0001)

Also there was significant difference in the density of matureand regenerating phase among all vegetation types exceptWOOD (DECI 119865

1130= 117 119875 lt 0001 SEMI 119865

1269= 37

119875 lt 005 EVER 1198651255= 73 119875 lt 0008 WOOD 119865

141= 34

119875 lt 0059 SUBM 1198651201= 101 119875 lt 0002 MONT 119865

188=

51 119875 lt 0026)The overall changes in species composition from mature

stage to regenerating stage (sapling + seedling phases) ofdifferent vegetation types 21 that is 79 similarity (usingSorenson index of similarity) between mature and regenerat-ing phase In disturbed WOOD and DECI the similarity inspecies composition between mature trees and regeneratingindividuals was 49 and 69 respectively In little-disturbedvegetation types species similarity between mature trees andregenerating phases was relatively high In all the forest typesnew entry species (tree species with no adult stages) werepresent Percent of new entry species was highest in fireaffected WOOD vegetation (Table 3)

4 Discussion

41 Species Diversity Theuse of species-individuals curves inaddition to species-area curves provides a clear insight intospecies diversity More sampling area is required for speciesrich vegetation type compared to species poor one and ingeneral the minimum area varies with number of speciesfrom one vegetation type to another [51] In our data species-rich communities like SEMI and EVER seem to have lessdominance than species-poor communities However lowerrarefaction curve in MONT suggests that abundance effectmay not be the sole reason for high richness The accumu-lation of new species with increasing sampling effort canbe visualized with a species accumulation curve Increasing

8 ISRN Ecology

0

20

40

60

80

100

Frequency classes

DECI

0ndash20 21ndash40 41ndash60 61ndash80 81ndash100

Spec

ies (

)

(a)

0

20

40

60

80

100SEMI

Frequency classes0ndash20 21ndash40 41ndash60 61ndash80 81ndash100

Spec

ies (

)

(b)

0

20

40

60

80

100

EVER

Frequency classes0ndash20 21ndash40 41ndash60 61ndash80 81ndash100

Spec

ies (

)

(c)

0

20

40

60

80

100

WOOD

Frequency classes0ndash20 21ndash40 41ndash60 61ndash80 81ndash100

Spec

ies (

)

(d)

0

20

40

60

80

100

SUBM

Frequency classes0ndash20 21ndash40 41ndash60 61ndash80 81ndash100

Mature treesSaplingsSeedlings

Spec

ies (

)

(e)

0

20

40

60

80

100

MONT

Mature treesSaplingsSeedlings

Frequency classes0ndash20 21ndash40 41ndash60 61ndash80 81ndash100

Spec

ies (

)

(f)

Figure 5 Percent frequencies of trees (ge30 cm gbh) in different vegetation types Most of the species were in the lowest frequency class inall vegetation types other than MONT indicating that a few species were widely distributed most were restricted in distribution This is atypical species-abundance distribution (normal distribution) and the tree species in all the vegetation type were heterogeneous distributionin Raunkiaerrsquos sense

the area sampled increases observed species richness bothbecause more individuals get included in the sample andbecause large areas are environmentally more heterogeneousthan small areas [52] The correlation between species rich-ness and abundance suggests that process affecting change ineither richness or abundance also affects species diversity

Species richness of DECI was reduced likely due to lowrainfall and anthropogenic disturbances such as firewoodcollection and cattle grazing In fire affected WOOD grasseswere the dominant life forms these were intermingled with afew fire tolerant light demanding trees High species richnessof trees in SEMI EVER and SUBM was probably relatedto high rainfall and optimal climatic conditions (Table 2)Low temperature and high wind velocity in the MONT may

negatively impact tree growth and reduce species richnessthere DECI standswere dominated bymembers of the familyFabaceae while Euphorbiaceae and Rubiaceae dominated inEVER at mid elevations High elevation SUBM and MONTwere dominated bymembers of the Lauraceae andMyrtaceaewhich have volatile oils in their tissues that resist freezingdamage in plant cells [53]

Compared to DECI tree species diversity was very highin other forest types at higher elevations other than in thefire-affected WOOD High species diversity of SEMI is dueits transitional nature that is this vegetation type is ecotonearea suitable for both deciduous and evergreen tree species sothere is an increase in the number of species Species diversityindices for saplings were lower than those for mature trees

ISRN Ecology 9

3721 19 10 6 3 2 1 1

020406080

100DECI

Tree

s (

)

Girth classes

10ndash5

0

101ndash

150

151ndash

200

201ndash

250

251ndash

300

301ndash

350

351ndash

400

51ndash1

00

gt400

(a)

020406080

10060

20 9 3 2 2 21 1

SEMI

Tree

s (

)

Girth classes

10ndash5

0

101ndash

150

151ndash

200

201ndash

250

251ndash

300

301ndash

350

351ndash

400

51ndash1

00

gt400

(b)

020406080

10065

19 9 3 2 2 21 1

EVER

Tree

s (

)

Girth classes

10ndash5

0

101ndash

150

151ndash

200

201ndash

250

251ndash

300

301ndash

350

351ndash

400

51ndash1

00

gt400

(c)

020406080

100 96

4 0 0 0 0 0 0 0

WOOD

Tree

s (

)

Girth classes

10ndash5

0

101ndash

150

151ndash

200

201ndash

250

251ndash

300

301ndash

350

351ndash

400

51ndash1

00

gt400

(d)

020406080

10058

20 12 4 2 1 1 1 1

SUBM

Girth classes

10ndash5

0

101ndash

150

151ndash

200

201ndash

250

251ndash

300

301ndash

350

351ndash

400

Tree

s (

)

51ndash1

00

gt400

(e)

020406080

10070

243 2 1 0 0 0 0

MONT

Tree

s (

)

Girth classes

10ndash5

0

101ndash

150

151ndash

200

201ndash

250

251ndash

300

301ndash

350

351ndash

400

51ndash1

00

gt400

(f)

Figure 6 Girth frequency distributions of trees in different vegetation types of the study area Girth-size was highest in SEMI and EVER Ahigh percentage of lower girth class trees in DECI results from reduced fuel wood extraction by people of nearby areas The reverse J-shapedgbh distribution of trees indicates evolving or expanding population

and seedlings in DECI is due to overharvesting of saplingsfor firewood The lowest species diversity value in WOODindicates low species richness and dominance of one or twospecies in the tree community In the present study Shannonindex values for tree species are similar to values for othertropical forests of the world (Table 4) However detailedcomparisons with other studies are inadvisable because oflarge differences in sample size standard girth parametersand environmental conditions

Density and frequency distributions of trees contributeto the structure of tropical forests Tree density in DECI wasmuch lower than that of other forest types perhaps due to lowrainfall and anthropogenic disturbances Density was least inthe fire-affected WOOD Sapling densities were elevated inSEMI and EVER Late secondary successional species werewell represented in the sapling population of EVER whichmay be indicative of recent natural disturbances in this foresttype that promoted regeneration of late secondary speciesMONT had high sapling density due to the stunted nature oftrees caused by very low temperature and high wind velocityprevalent there [54]

Densities of trees in the study area were similar toestimates from tropical forests within India and other tropicalregions (Table 4) In tropical forests outside India there ismuch variation in the densities of trees gt30 cm gbh (98ndash1930 trees haminus1) especially in Amazonian forests In theNeotropics maximum species richness of tree individualsgt10 cm gbh reaches 300 haminus1 [55] In South-East Asia thehighest richness is 225 haminus1 [56]

In the present studymost of the species were in frequencyclass 0ndash20 and fewest were in frequency class 80ndash100The frequency distribution of tree species suggested thatmostof them had low frequency as would be expected in typicalspecies-abundance distribution A plant species should beconsidered homogeneously distributed when the numbersof individuals are the same in all parts of a community[50] Hence tree species in all the vegetation types of thestudy area were heterogeneously distributed Girth classfrequency distributions of most species in vegetation typeswe studied fit ldquoreverse Jrdquo-shaped patterns with most trees insmaller girth classes and few old trees Vegetation types otherthan WOOD fit negative exponential patterns indicative of

10 ISRN Ecology

Table4Ve

getatio

nparameterso

fforestcom

mun

ities

inthetropics

ofIndiaa

ndotherc

ountrie

s

Foresttypes

Locatio

nPlot

size(ha)

Tree

girth

studied

(cm)

Tree

density

(noha)

Tree

basal

area

(m2 ha)

Shanno

nindex

References

Presentstudy

DEC

IWestern

Ghats(N

BR)

4ha

ge30

cm132

234

279

Present

study

SEMI

ldquo4ha

ge30

cm368

457

367

ldquo

EVER

ldquo4ha

ge30

cm485

480

334

ldquo

WOOD

ldquo3ha

ge30

cm39

069

221

ldquo

SUBM

ldquo4ha

ge30

cm390

365

326

ldquo

MONT

ldquo4ha

ge30

cm855

309

321

ldquo

India

Evergreenforests

Silent

valleyWestern

Ghat

mdashge315

620ndash

709

29ndash103

mdash[6]

Moistdecidu

ousforests

Pepp

araWGhats

mdashge30

590ndash

740

13ndash51

2ndash33

[7]

Moistdecidu

ousforests

Chim

mon

yWestern

Ghats

mdashge30

558

3719

ndash24

[8]

Semievergreen

forests

Pepp

araWestern

Ghats

mdashge30

670ndash

940

45ndash6

229

[7]

Semievergreen

forests

Chim

mon

yWestern

Ghats

mdashge30

728

4727ndash32

[8]

Scrubjung

leto

wetevergreenforests

Kalakk

adRF

Western

Ghats

02

gt20

320ndash

1260

18ndash107

mdash[9]

Evergreenforests

Karnataka

044

mdash44

6ndash1386

33ndash4

8mdash

[10]

Evergreenforests

Pepp

ara

mdashge30

860ndash

1370

7633

[7]

Evergreenforests

NelliampathiWestern

Ghats

mdashge30

mdash498

3ndash37

[11]

Dry

tropicalforests

Vind

hyar

egion

mdashgt30

294ndash

559

7ndash23

mdash[12]

Dry

evergreenforests

Puthup

etSacred

GroveC

orom

andel

coast

02

gt20

280

11mdash

[13]

Trop

icalwe

tevergreen

forests

Kalakk

ad-M

undanthu

raiT

iger

Reserve

Western

Ghats

050

gt30

315ndash418

54ndash8

4mdash

[14]

Trop

icalwe

tevergreen

forests

KodayarWestern

Ghats

050

gt30

352ndash117

328ndash81

mdash[15]

Subtropicalh

illforests

Pepp

araWestern

Ghats

mdashge30

1580ndash1930

27ndash34

27

[7]

Mon

tane

temperateforests

Mannavanshola

mdashge30

566

52399

[16]

ISRN Ecology 11

Table4Con

tinued

Foresttypes

Locatio

nPlot

size(ha)

Tree

girth

studied

(cm)

Tree

density

(noha)

Tree

basal

area

(m2 ha)

Shanno

nindex

References

Other

coun

tries

Trop

icalrain

forests

(you

ngforests

)Ba

rrow

ColoradoIsland

Panam

a5

gt18

84ndash171

26ndash

52

mdash[17]

Trop

icalrain

forests

(old

forests

)Ba

rrow

ColoradoIsland

Panam

a50

gt18

143ndash177

43ndash5

mdash[18]

Trop

icalrain

forests

Amazon

ia3

314

1420

28ndash6

8mdash

[19]

Equatoria

linsular

forests

Easte

rnCa

rolline

Island

Panam

a50

gt314

98ndash114

17mdash

[20]

Trop

icalrain

forests

Jung

kaRe

serveMalaysia

1191

104

23mdash

[21]

Trop

icalrain

forests

Gun

ungSilamM

alaysia

004

314

513ndash1596

23ndash4

6mdash

[22]

Trop

icalmoistforests

Sing

apore

04

gt63

604

mdashmdash

[23]

Trop

icalrain

forests

Valcan

BarvaCostaRica

6gt314

391ndash617

mdashmdash

[24]

Slop

eforests

New

Caledo

nia

28

gt314

1533

49mdash

[25]

Allu

vium

forests

New

Caledo

nia

26

gt314

1183

47mdash

[25]

Equatoria

lforests

KongoIsland

mdashmdash

440ndash

553

10ndash4

5mdash

[26]

Trop

icalrain

forests

Amazon

ia3

gt314

1720

78mdash

[19]

Trop

icalseason

alrain

forests

Xishuang

bann

aCh

ina

2500

m2

15154

mdash34

[27]

Trop

icalmon

tane

rain

forests

Xishuang

bann

aCh

ina

1600

m2

15123

mdash32

[27]

Evergreenbroadleaved

forests

Xishuang

bann

aCh

ina

1200

m2

15165

mdash25

[27]

Mon

soon

forests

Xishuang

bann

aCh

ina

400m

210

150

mdash16

[27]

ldquoStudy

cond

uctedin

6different

vegetatio

ntypeso

fWestern

Ghats(N

BR)

12 ISRN Ecology

relatively undisturbed or less disturbed conditions in thestands The high annual precipitation rate and optimumtemperature of EVER may have contributed to high treegrowth rate and higher tree basal area

42 Regeneration All other vegetation types had betterregeneration than DECI In WOOD the transition rate ofstems from small girth classes to larger girth classes was lowPoor tree regeneration in DECI and WOOD can probablybe attributed to fuel wood collection frequent fires andgrazing by cattle In all forest types 29ndash47 of tree specieswere present in all three growth phases other species werepresent in either one or two growth phases Dominant speciesoccurred in all girth classes of vegetation types other thanWOOD in whichmost trees were in the smaller girth classesThere were more large trees in vegetation types like SEMIand EVER and in these sapling and seedling densities wereadequate for restocking the complement of canopy trees

Change in species composition across mature and regen-erating tree phases was more frequent in disturbed foresttypes like DECI and WOOD In some cases the dominantspecies in adult and seedling stages were quite differentin these two disturbed forest types Our results are notcongruent with observationsmade in northeastern India [39]where tree seedling survival rate increases with increasingforest disturbance We found species without regeneratingphases these are unlikely to persist Others that occurred onlyin seedling and sapling stages were new entrants to the forestspecies complement These are examples of discontinuouspopulation structures Such structures occur in a number ofother tropical countries [57ndash59] The dominant species in aforest stand is generally present in all size classes [38] Thesize class structures of trees indicate the probability of speciespersistence into the future this information is very valuablein the design of management strategies aiming to improvestand structure and species diversity Changes in speciescomposition and recruitment of new species in differentvegetation types are indicative of future species compositionin changing environments

5 Conclusions

The species diversity of trees varied across vegetation types inthe Western Ghats landscape Rarefaction curves show thatspecies diversity is highest in SEMI and EVER and lowest inWOOD while species abundance is highest in MONT Vege-tation types of study area are in heterogeneous in distributionThere were large differences in species composition of adulttrees and regenerating individuals in the disturbed vegetationtypes as compared to undisturbed stands The present studyreveals that the anthropogenic disturbance causes disruptionof forest structure and change in species composition whichultimately leads to reduction of tree species richness andabundance which are the major attributes of forests Newrecruits were found in all vegetation types indicating thattheywere not headed to extinction however disturbed standsmay move to new species compositions in the future

Acknowledgments

The authors are thankful to the Ministry of Environmentand Forests for financial support and the Vice Chancellorof University of Delhi and the Director of Kerala ForestResearch Institute for facilities provided The first authorwould like to thank Professor C R Babu for facilities andencouragement The authors are very much obliged to allmembers of the Cholanaikkan tribe who helped duringthe field survey The Kerala Forest Department provided alllogistical support for the floristic and ecological survey of theforest area (trees haminus1) in three different growth phases of sixvegetation

References

[1] M A Huston Biological Diversity The Coexistence of Species inChanging Landscapes Cambridge University Press CambridgeUK 1994

[2] T C Whitmore An Introduction to Tropical Rain ForestsOxfordUniversity Press NewYork NYUSA 2nd edition 1998

[3] M L Khan S Menon and K S Bawa ldquoEffectiveness of theprotected area network in biodiversity conservation a case-study of Meghalaya staterdquo Biodiversity and Conservation vol 6no 6 pp 853ndash868 1997

[4] C M Pringle ldquoNutrient spatial heterogeneity effects on com-munity structure physiognomy and diversity of stream algaerdquoEcology vol 71 no 3 pp 905ndash920 1990

[5] M Parviainen M Marmion M Luoto W Thuiller and RK Heikkinen ldquoUsing summed individual species models andstate-of-the-art modelling techniques to identify threatenedplant species hotspotsrdquo Biological Conservation vol 142 no 11pp 2501ndash2509 2009

[6] J S Singh S P Singh A K Saxena and Y S Ravat ldquoThe forestvegetation of Silent Valleyrdquo in Tropical Rain Forests The LeedsSymposium pp 25ndash52 1984

[7] A O Varghese ldquoAssessment of biodiversity of PepparaWildlifeSanctuary Trivandrum District Keralardquo Journal of Economicand Taxonomic Botany vol 23 pp 117ndash127 1998

[8] M A Suraj Phytosociological and vagetation mapping at chim-mony wildlife Sanctuary (Kerala) using remote sensing technique[PhD thesis] FRI University Dehradun India 1997

[9] N Parthasarathy Studies on the vacular flora structure andnutrient cycling in Kalakad Reserve Forest Western Ghats TamilNadu [PhD thesis] University of Madras Tamil Nadu India1986

[10] S N Rai and J Proctor ldquoEcological studies on four rainforests in Karnataka India environment forest structure andvegetationrdquo Journal of Vegetation Science vol 1 pp 609ndash6141986

[11] U M Chadrashekara A R R Menon K K N Nair NSasidharan and K Swarupanandan ldquoEvaluating plant diversityin different forest types of Kerala by laying out permanent sam-ple plotsrdquo KFRI Research Report 156 Kerala Forest ResearchInstitute Peechi India 1998

[12] C S Jha and J S Singh ldquoComposition and dynamics of drytropical Forest in relation to soil texturerdquo Journal of VegetationScience vol 1 no 5 pp 609ndash614 1990

[13] NVisalakshi ldquoVegetation analysis of two tropical dry evergreenforests in southern IndiardquoTropical Ecology vol 36 no 1 pp 117ndash127 1995

ISRN Ecology 13

[14] T Ganesh R Ganesan M Soubadra Devy P Davidar and K SBawa ldquoAssessment of plant biodiversity at amid-elevation ever-green forest of Kalakad-Mundanthurai Tiger Reserve WesternGhats Indiardquo Current Science vol 71 no 5 pp 379ndash392 1996

[15] S M Sundarapandian and P S Swamy ldquoForest ecosystemstructure and composition along an altitudinal gradient in theWestern Ghats South Indiardquo Journal of Tropical Forest Sciencevol 12 no 1 pp 104ndash123 2000

[16] K Swarupanandan N Sasidharan K C Chacko and SChanduBasha ldquoFloristic and ecological studies on the Sholasof Idukki Districtrdquo in Shola Forests of Kerala Environmentand Biodiverstiy K K N Nair S K Khanduri and K Bala-subramaniayan Eds pp 259ndash286 Kerala Forest DeparmentThiruvanathapuram Kerala Forest Research Institute PeechiIndia 2001

[17] R W Thorington S Tannenbaum A Tarak and R RudranldquoDistribution of trees in Baro Colorado Islands a hectaresamplerdquo in The Ecology of a Tropical Forest-Seasonal Rhythmsand Long-term Changes E G Leigh Jr A S Rand and D MWindsor Eds Smithsonian Institute Press Washington DCUSA 1982

[18] S P Hubbell and R B Foster ldquoDiversity of canopy speciesin a neotropical forest and implications for conservationrdquo inTropical Rain Forest Ecology and Management S L Sutton TCWhitmore andA C Chadwick Eds Blackwell Oxford UK1983

[19] D G Campbell D C Daly G T Prance and U N MacielldquoQuantitative ecological inventory of terra firme and varzeatropical forest on the Rio Xingu Brazilian Amazonrdquo Brittoniavol 38 no 4 pp 369ndash393 1986

[20] S Itow ldquoSpecies diversity of equatorial insular forests on Ponapeand Kosrae Micronesiardquo Ecological Research vol 1 no 2 pp223ndash227 1986

[21] C C Ho D M Newbery and M E D Poore ldquoForestcomposition and inferred dynamics in Jengka Forest ReserveMalaysiardquo Journal of Tropical Ecology vol 3 no 1 pp 25ndash561987

[22] J Proctor Y F Lee A M Langley W R C Munro and TNelson ldquoEcological studies onGunung Silam a small ultrabasicmountain Sabah Malaysiardquo Journal of Ecology vol 74 pp 455ndash463 1988

[23] F R Swan Jr ldquoTree distribution patterns in the Bukittimahnature reserve Singaporerdquo Gardens Bulletin vol 41 pp 59ndash811988

[24] A Heaney and J Proctor ldquoPreliminary studies on foreststructure and floristics on Volcan Barva Costa Ricardquo Journalof Tropical Ecology vol 6 no 3 pp 307ndash320 1990

[25] T Jaffre and J M Veillon ldquoEtude floristique et structuralede deux forets denses humides sur roches ultrabasiques enNouvelle- Caledonierdquo Bulletin du Museum National drsquoHistoireNaturelle vol 12 pp 243ndash273 1990

[26] MMosango ldquoContribution ldquoA lrsquoetude botanic biogeo 1rdquo ecosys-tem Foret en region equatorial (Ile KongoloZaire)rdquo BelgiumJournal of Botany vol 124 pp 167ndash194 1991

[27] M Cao and J Zhang ldquoTree species diversity of tropical forestvegetation in Xishuangbanna SW Chinardquo Biodiversity andConservation vol 6 no 7 pp 995ndash1006 1997

[28] C S Jha L Goparaju A Tripathi B Gharai A S Raghubanshiand J S Singh ldquoForest fragmentation and its impact onspecies diversity an analysis using remote sensing and GISrdquoBiodiversity and Conservation vol 14 no 7 pp 1681ndash1698 2005

[29] P S Roy C B S Dutt and P K Joshi ldquoTropical forest resourceassessment and monitoringrdquo Tropical Ecology vol 43 no 1 pp21ndash37 2002

[30] R Sagar A S Raghubanshi and J S Singh ldquoAsymptoticmodelsof species-area curve for measuring diversity of dry tropicalforest tree speciesrdquo Current Science vol 84 no 12 pp 1555ndash1560 2003

[31] R Sukumar H S Dattaraja H S Suresh et al ldquoLong-termmonitoring of vegetation in a tropical deciduous forest inMudumalai southern Indiardquo Current Science vol 62 pp 608ndash616 1992

[32] UMChandrashekara and P S Ramakrishnan ldquoVegetation andgap dynamics of a tropical wet evergreen forest in the WesternGhats of Kerala Indiardquo Journal of Tropical Ecology vol 10 no3 pp 337ndash354 1994

[33] T Ganesh R Ganesan M Soubadra Devy P Davidar and K SBawa ldquoAssessment of plant biodiversity at amid-elevation ever-green forest of Kalakad-Mundanthurai Tiger Reserve WesternGhats Indiardquo Current Science vol 71 no 5 pp 379ndash392 1996

[34] J P Pascal and R Pelissier ldquoStructure and floristic compositionof a tropical evergreen forest in south-west Indiardquo Journal ofTropical Ecology vol 12 no 2 pp 191ndash210 1996

[35] N Ayyappan and N Parthasarathy ldquoBiodiversity inventory oftrees in a large-scale permanent plot of tropical evergreen forestat Varagalaiar Anamalais Western Ghats Indiardquo Biodiversityand Conservation vol 8 no 11 pp 1533ndash1554 1999

[36] A Kumar B G Marcot and A Saxena ldquoTree species diversityand distribution patterns in tropical forests of Garo HillsrdquoCurrent Science vol 91 no 10 pp 1370ndash1381 2006

[37] N Parthasarathy ldquoTree diversity and distribution in undis-turbed and human-impacted sites of tropical wet evergreenforest in southern Western Ghats Indiardquo Biodiversity andConservation vol 8 no 10 pp 1365ndash1381 1999

[38] M L Khan J P N Rai and R S Tripathi ldquoPopulation structureof some tree species in disturbed and protected subtropicalforests of north-east Indiardquo Acta Oecologica vol 8 no 3 pp247ndash255 1987

[39] R S Tripathi and M L Khan ldquoRegeneration pattern andpopulation structure of trees in subtropical forest of North EastIndiardquo in Tropical Ecosystem-Ecology and Management K PSingh and J S Singh Eds pp 431ndash441 Wiley Eastern LimitedNew Delhi India 1992

[40] A E Scholl and A H Taylor ldquoRegeneration patterns in old-growth red fir-western white pine forests in the northern SierraNevada Lake Tahoe USArdquo Forest Ecology and Managementvol 235 no 1ndash3 pp 143ndash154 2006

[41] D A Clark ldquoRegeneration of canopy trees in tropical wetforestsrdquo Trends in Ecology and Evolution vol 1 no 6 pp 150ndash154 1986

[42] P C J Barker and J B Kirkpatrick ldquoPhyllocladus aspleniifoliusvariability in the population structure the regeneration nicheand dispersion patterns in Tasmanian forestsrdquo Australian Jour-nal of Botany vol 42 no 2 pp 163ndash190 1994

[43] C K Augspurger ldquoSeedling survival of tropical tree speciesinteractions of dispersal distance light-gaps and pathogensrdquoEcology vol 65 no 6 pp 1705ndash1712 1984

[44] O L Phillips ldquoLong-term environmental change in tropicalforests increasing tree turnoverrdquo Environmental Conservationvol 23 no 3 pp 235ndash248 1996

[45] Ministry of Environment and Forests ldquoPlant discoveries 2011newgenera species andnew recordsrdquo Botanical Survey of IndiaMinistry of Environment and Forests New Delhi India 2012

14 ISRN Ecology

[46] ldquoWeblink 2007rdquo httpwwwbiodiversityhotspotsorgxphot-spotshotspots by region

[47] D Mueller-Dombois and H Ellenberg Aims and Methods ofPlant Ecology John Wiley amp Sons New York NY USA 1974

[48] K K N Nair and R Jayakumar ldquoPhytogeography endemismand affinities of the flora of NewAmarambalamReserve Forestsin theWesternGhats of Indiardquo Indian Journal of Forestry vol 31pp 85ndash94 2008

[49] A E Magurran Ecological Diversity and Its MeasurementCroom Helm Ltd London UK 1988

[50] C Raunkiaer The Life Forms of Plants and Statistical PlantGeography Clarendon Press Oxford UK 1934

[51] B Rice andMWestoby ldquoPlant species richness at the 01 hectarescale in Australian vegetation compared to other continentsrdquoVegetatio vol 52 no 3 pp 129ndash140 1983

[52] SM Scheiner ldquoSix types of species-area curvesrdquoGlobal Ecologyand Biogeography vol 12 no 6 pp 441ndash447 2003

[53] H G Jones Plants and Microclimate Cambridge UniversityPress Cambridge UK 1983

[54] N C Nair The Southern Western Ghats A Biodiversity Con-servation Plan Indian National Trust for Arts and CulturalHeritage New Delhi India 1991

[55] AHGentry ldquoChanges in plant community diversity and floris-tic composition on environmental and geographical gradientrdquoAnnals of the Missouri Botanical Garden vol 75 no 1 pp 1ndash341988

[56] T CWhitmore Tropical Rain Forests of the Far East ClarendonPress Oxford UK 1984

[57] N V L Brokaw ldquoGap-phase regeneration of three pioneer treespecies in a tropical forestrdquo Journal of Ecology vol 75 no 1 pp9ndash19 1987

[58] S Itow and D Mueller-Dombois ldquoPopulation structure stand-level dieback and recovery of Scalesia pedunculata forest in theGalapagos Islandsrdquo Ecological Research vol 3 no 3 pp 333ndash339 1988

[59] T CWhitmore ldquoA review of some aspects of tropical rainforestseedling ecology with suggestions for further enquiryrdquo inEcology of Tropical Forest Tree Seedlings M D Swaine Ed pp3ndash39 UNESCOParthenon Paris France 1996

Submit your manuscripts athttpwwwhindawicom

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ClimatologyJournal of

Page 6: Research Article Species Diversity and Tree Regeneration ...downloads.hindawi.com/archive/2013/890862.pdf · Species Diversity and Tree Regeneration Patterns in Tropical Forests of

6 ISRN Ecology

DECISEMIEVER

WOODSUBMMONT

120

100

80

60

40

20

0

Spec

ies

0 05 1 15 2 25Area (ha)

(a)

0

20

40

60

80

100

120

140

0 200 400 600 800 1000 1200 1400 1600 1800

Spec

ies

Individuals

DECISEMIEVER

WOODSUBMMONT

(b)

Figure 3 Species accumulation and rarefaction curves of different vegetation types Curves were created random series of 30 plots of 009 ha(ie 27 ha for each vegetation type) (a) Species-area curves (sample-based rarefaction) and (b) species-individuals curve (individuals-basedrarefaction) Looking at the individual-based rarefaction curve all four vegetation types seem to be quite similar in species richness exceptMONT which is drastically lower although containing the highest number of individuals WOOD which contain too few individuals toproduce a comparable result The sample-based rarefaction on the other hand identifies SEMI and EVER as the two most species richcommunities differing from the rest Rarefaction curves for six vegetation types predict the rate of accumulation of species with increasingnumber of individuals (abundance) See Table 1 for an explanation of vegetation type abbreviations

Table 2 Vegetation parameters calculated for three tree phases in different vegetation types See Table 1 for explanation of vegetation typeabbreviations

Vegetation types(Altitude range)

Rainfall(mm)

Mean temperaturein the coldestmonth (∘C)

Phases oftrees

Basal area(m2ha)

Shannonindex

DECI(40ndash400m) 1000ndash1500 28

Mature treesSaplingsSeedlings

2332020mdash

279248262

SEMI(400ndash650m)

2500ndash3500 24 Mature treesSaplingsSeedlings

4566089mdash

367315311

EVER(650ndash1200m)

3500ndash5000 22 Mature treesSaplingsSeedlings

4800124mdash

334309349

WOOD(900ndash1400m)

3500ndash5000 25 Mature treesSaplingsSeedlings

06904mdash

221216156

SUBM(1200ndash1800m)

5000ndash6000 13 Mature treesSaplingsSeedlings

3651069mdash

326345351

MONT(1800ndash2450m)

5000ndash6000 9 Mature treesSaplingsSeedlings

3087145mdash

321319271

lowastMature trees (ge30 cm gbh) saplings (ge 10lt 30 cm gbh) and seedlings (lt10 cm gbh)

of trees were in the smallest girth class (Figure 6) In WOODvegetation which was fire affected and grass dominated 96of trees were in the smallest girth class

32 Regeneration Frequencies of regenerating species(saplings + seedlings) were maximal in undisturbed forestcompared to disturbed one (caused by fuel wood collection

and cattle grazing) In DECI of 71 taxa recorded only 26were present in all three growth phases 24 were presentin only one stage and only 10 species were regeneratingwell (seedling gt sapling gt tree) Nevertheless Lagerstroemiamicrocarpa one of the dominant species in DECI hadno seedlings indicative of poor regeneration potential(Tables 1 and 3 see Supplementary Material Appendix 1available online at httpdxdoiorg1011552013890862)

ISRN Ecology 7

Table 3 Distribution pattern of mature and regenerating phases of trees occur in different vegetation types Regenerating species and speciesshare in all phases of trees was lower in disturbed vegetation type such as DECI and WOOD as compared to other vegetation types Percentsimilarity in species composition (using Sorenson index of similarity) of mature trees and regenerating individuals (saplings + seedlings) indifferent vegetation types of the study area and new species recruited (trees devoid of adult stage) are also shown

Vegetationtypes

Tree species occur inlowastRegeneratingspecies ()

Similarity betweenmature trees andregenerating individuals

New entryspecies ()All phases () Mature phase

only ()Regeneratingphase only ()

DECI 26 (37) 21 (30) 12 (17) 50 (70) 69 12 (17)SEMI 53 (41) 11 (9) 27 (21) 116 (91) 82 24 (18)EVER 49 (40) 11 (9) 24 (20) 111 (91) 81 23 (18)WOOD 8 (29) 8 (29) 11 (39) 20 (71) 49 10 (35)SUBM 40 (43) 4 (4) 18 (20) 87 (95) 88 20 (21)MONT 20 (47) 6 (14) 11 (26) 37 (86) 76 10 (23)lowastA number of species occur in saplings andor seedlings and these species may or may not have mature tree stage of species has been given in brackets

132 36

8

485

39

390 85

5

65

250 393

77

215 39

22073 95

57

7717

795

6971 16

395

1

10

100

1000

10000

100000

DECI SEMI EVER WOOD SUBM MONT

Den

sity

Vegetation types

Mature treesSaplingsSeedlings

Figure 4 Densities (no haminus1 in log10scale) of mature trees (ge30 cm

gbh (girth at breast height)) saplings (ge 10 lt 30 cm gbh) and seedl-ings (lt10 cm gbh) in six vegetation types occurring in the WesternGhats LSD post hoc test clarified that density of disturbed forestlike DECI and WOOD was significantly different with undisturbedvegetation type except MONT

In vegetation types influenced by disturbance and firelike WOOD 29 of species were common in all growthphases and seedling richness was very low in these types ofvegetation (Supplementary Material Appendix 2)

In vegetation types at mid elevations namely EVERand SEMI 49ndash53 of species were present in all growthphases 25ndash30 of species occurred in only one phase(Supplementary Material Appendices 3 and 4) In forestsat higher elevations namelySUBM and MONT 43 and47 of species respectively were present in all growthphases In SUBM 25 species had poor regeneration potential(Supplementary Material Appendix 5) In MONT 20 specieswere present in all growth phases and 12 had no regenerationpotential (Table 3 Supplementary Material Appendix 6)

33 Change in Species Composition among Tree Phases Over-all species richness of mature trees was higher than richnessof saplings and seedlings in all vegetation types Among the

dominant species a few trees had exceptionally large num-bers of seedling and saplings Individual trees did notcontribute equally to the seedling population or to laterrecruitment in the sapling stage Density of regeneratingindividuals (saplings + seedlings) was highest in EVER andlowest in WOOD There was significant difference in thedensity of regenerating individuals (seedling + saplings)among different vegetation types (119865

5611= 132 119875 lt 0001)

Also there was significant difference in the density of matureand regenerating phase among all vegetation types exceptWOOD (DECI 119865

1130= 117 119875 lt 0001 SEMI 119865

1269= 37

119875 lt 005 EVER 1198651255= 73 119875 lt 0008 WOOD 119865

141= 34

119875 lt 0059 SUBM 1198651201= 101 119875 lt 0002 MONT 119865

188=

51 119875 lt 0026)The overall changes in species composition from mature

stage to regenerating stage (sapling + seedling phases) ofdifferent vegetation types 21 that is 79 similarity (usingSorenson index of similarity) between mature and regenerat-ing phase In disturbed WOOD and DECI the similarity inspecies composition between mature trees and regeneratingindividuals was 49 and 69 respectively In little-disturbedvegetation types species similarity between mature trees andregenerating phases was relatively high In all the forest typesnew entry species (tree species with no adult stages) werepresent Percent of new entry species was highest in fireaffected WOOD vegetation (Table 3)

4 Discussion

41 Species Diversity Theuse of species-individuals curves inaddition to species-area curves provides a clear insight intospecies diversity More sampling area is required for speciesrich vegetation type compared to species poor one and ingeneral the minimum area varies with number of speciesfrom one vegetation type to another [51] In our data species-rich communities like SEMI and EVER seem to have lessdominance than species-poor communities However lowerrarefaction curve in MONT suggests that abundance effectmay not be the sole reason for high richness The accumu-lation of new species with increasing sampling effort canbe visualized with a species accumulation curve Increasing

8 ISRN Ecology

0

20

40

60

80

100

Frequency classes

DECI

0ndash20 21ndash40 41ndash60 61ndash80 81ndash100

Spec

ies (

)

(a)

0

20

40

60

80

100SEMI

Frequency classes0ndash20 21ndash40 41ndash60 61ndash80 81ndash100

Spec

ies (

)

(b)

0

20

40

60

80

100

EVER

Frequency classes0ndash20 21ndash40 41ndash60 61ndash80 81ndash100

Spec

ies (

)

(c)

0

20

40

60

80

100

WOOD

Frequency classes0ndash20 21ndash40 41ndash60 61ndash80 81ndash100

Spec

ies (

)

(d)

0

20

40

60

80

100

SUBM

Frequency classes0ndash20 21ndash40 41ndash60 61ndash80 81ndash100

Mature treesSaplingsSeedlings

Spec

ies (

)

(e)

0

20

40

60

80

100

MONT

Mature treesSaplingsSeedlings

Frequency classes0ndash20 21ndash40 41ndash60 61ndash80 81ndash100

Spec

ies (

)

(f)

Figure 5 Percent frequencies of trees (ge30 cm gbh) in different vegetation types Most of the species were in the lowest frequency class inall vegetation types other than MONT indicating that a few species were widely distributed most were restricted in distribution This is atypical species-abundance distribution (normal distribution) and the tree species in all the vegetation type were heterogeneous distributionin Raunkiaerrsquos sense

the area sampled increases observed species richness bothbecause more individuals get included in the sample andbecause large areas are environmentally more heterogeneousthan small areas [52] The correlation between species rich-ness and abundance suggests that process affecting change ineither richness or abundance also affects species diversity

Species richness of DECI was reduced likely due to lowrainfall and anthropogenic disturbances such as firewoodcollection and cattle grazing In fire affected WOOD grasseswere the dominant life forms these were intermingled with afew fire tolerant light demanding trees High species richnessof trees in SEMI EVER and SUBM was probably relatedto high rainfall and optimal climatic conditions (Table 2)Low temperature and high wind velocity in the MONT may

negatively impact tree growth and reduce species richnessthere DECI standswere dominated bymembers of the familyFabaceae while Euphorbiaceae and Rubiaceae dominated inEVER at mid elevations High elevation SUBM and MONTwere dominated bymembers of the Lauraceae andMyrtaceaewhich have volatile oils in their tissues that resist freezingdamage in plant cells [53]

Compared to DECI tree species diversity was very highin other forest types at higher elevations other than in thefire-affected WOOD High species diversity of SEMI is dueits transitional nature that is this vegetation type is ecotonearea suitable for both deciduous and evergreen tree species sothere is an increase in the number of species Species diversityindices for saplings were lower than those for mature trees

ISRN Ecology 9

3721 19 10 6 3 2 1 1

020406080

100DECI

Tree

s (

)

Girth classes

10ndash5

0

101ndash

150

151ndash

200

201ndash

250

251ndash

300

301ndash

350

351ndash

400

51ndash1

00

gt400

(a)

020406080

10060

20 9 3 2 2 21 1

SEMI

Tree

s (

)

Girth classes

10ndash5

0

101ndash

150

151ndash

200

201ndash

250

251ndash

300

301ndash

350

351ndash

400

51ndash1

00

gt400

(b)

020406080

10065

19 9 3 2 2 21 1

EVER

Tree

s (

)

Girth classes

10ndash5

0

101ndash

150

151ndash

200

201ndash

250

251ndash

300

301ndash

350

351ndash

400

51ndash1

00

gt400

(c)

020406080

100 96

4 0 0 0 0 0 0 0

WOOD

Tree

s (

)

Girth classes

10ndash5

0

101ndash

150

151ndash

200

201ndash

250

251ndash

300

301ndash

350

351ndash

400

51ndash1

00

gt400

(d)

020406080

10058

20 12 4 2 1 1 1 1

SUBM

Girth classes

10ndash5

0

101ndash

150

151ndash

200

201ndash

250

251ndash

300

301ndash

350

351ndash

400

Tree

s (

)

51ndash1

00

gt400

(e)

020406080

10070

243 2 1 0 0 0 0

MONT

Tree

s (

)

Girth classes

10ndash5

0

101ndash

150

151ndash

200

201ndash

250

251ndash

300

301ndash

350

351ndash

400

51ndash1

00

gt400

(f)

Figure 6 Girth frequency distributions of trees in different vegetation types of the study area Girth-size was highest in SEMI and EVER Ahigh percentage of lower girth class trees in DECI results from reduced fuel wood extraction by people of nearby areas The reverse J-shapedgbh distribution of trees indicates evolving or expanding population

and seedlings in DECI is due to overharvesting of saplingsfor firewood The lowest species diversity value in WOODindicates low species richness and dominance of one or twospecies in the tree community In the present study Shannonindex values for tree species are similar to values for othertropical forests of the world (Table 4) However detailedcomparisons with other studies are inadvisable because oflarge differences in sample size standard girth parametersand environmental conditions

Density and frequency distributions of trees contributeto the structure of tropical forests Tree density in DECI wasmuch lower than that of other forest types perhaps due to lowrainfall and anthropogenic disturbances Density was least inthe fire-affected WOOD Sapling densities were elevated inSEMI and EVER Late secondary successional species werewell represented in the sapling population of EVER whichmay be indicative of recent natural disturbances in this foresttype that promoted regeneration of late secondary speciesMONT had high sapling density due to the stunted nature oftrees caused by very low temperature and high wind velocityprevalent there [54]

Densities of trees in the study area were similar toestimates from tropical forests within India and other tropicalregions (Table 4) In tropical forests outside India there ismuch variation in the densities of trees gt30 cm gbh (98ndash1930 trees haminus1) especially in Amazonian forests In theNeotropics maximum species richness of tree individualsgt10 cm gbh reaches 300 haminus1 [55] In South-East Asia thehighest richness is 225 haminus1 [56]

In the present studymost of the species were in frequencyclass 0ndash20 and fewest were in frequency class 80ndash100The frequency distribution of tree species suggested thatmostof them had low frequency as would be expected in typicalspecies-abundance distribution A plant species should beconsidered homogeneously distributed when the numbersof individuals are the same in all parts of a community[50] Hence tree species in all the vegetation types of thestudy area were heterogeneously distributed Girth classfrequency distributions of most species in vegetation typeswe studied fit ldquoreverse Jrdquo-shaped patterns with most trees insmaller girth classes and few old trees Vegetation types otherthan WOOD fit negative exponential patterns indicative of

10 ISRN Ecology

Table4Ve

getatio

nparameterso

fforestcom

mun

ities

inthetropics

ofIndiaa

ndotherc

ountrie

s

Foresttypes

Locatio

nPlot

size(ha)

Tree

girth

studied

(cm)

Tree

density

(noha)

Tree

basal

area

(m2 ha)

Shanno

nindex

References

Presentstudy

DEC

IWestern

Ghats(N

BR)

4ha

ge30

cm132

234

279

Present

study

SEMI

ldquo4ha

ge30

cm368

457

367

ldquo

EVER

ldquo4ha

ge30

cm485

480

334

ldquo

WOOD

ldquo3ha

ge30

cm39

069

221

ldquo

SUBM

ldquo4ha

ge30

cm390

365

326

ldquo

MONT

ldquo4ha

ge30

cm855

309

321

ldquo

India

Evergreenforests

Silent

valleyWestern

Ghat

mdashge315

620ndash

709

29ndash103

mdash[6]

Moistdecidu

ousforests

Pepp

araWGhats

mdashge30

590ndash

740

13ndash51

2ndash33

[7]

Moistdecidu

ousforests

Chim

mon

yWestern

Ghats

mdashge30

558

3719

ndash24

[8]

Semievergreen

forests

Pepp

araWestern

Ghats

mdashge30

670ndash

940

45ndash6

229

[7]

Semievergreen

forests

Chim

mon

yWestern

Ghats

mdashge30

728

4727ndash32

[8]

Scrubjung

leto

wetevergreenforests

Kalakk

adRF

Western

Ghats

02

gt20

320ndash

1260

18ndash107

mdash[9]

Evergreenforests

Karnataka

044

mdash44

6ndash1386

33ndash4

8mdash

[10]

Evergreenforests

Pepp

ara

mdashge30

860ndash

1370

7633

[7]

Evergreenforests

NelliampathiWestern

Ghats

mdashge30

mdash498

3ndash37

[11]

Dry

tropicalforests

Vind

hyar

egion

mdashgt30

294ndash

559

7ndash23

mdash[12]

Dry

evergreenforests

Puthup

etSacred

GroveC

orom

andel

coast

02

gt20

280

11mdash

[13]

Trop

icalwe

tevergreen

forests

Kalakk

ad-M

undanthu

raiT

iger

Reserve

Western

Ghats

050

gt30

315ndash418

54ndash8

4mdash

[14]

Trop

icalwe

tevergreen

forests

KodayarWestern

Ghats

050

gt30

352ndash117

328ndash81

mdash[15]

Subtropicalh

illforests

Pepp

araWestern

Ghats

mdashge30

1580ndash1930

27ndash34

27

[7]

Mon

tane

temperateforests

Mannavanshola

mdashge30

566

52399

[16]

ISRN Ecology 11

Table4Con

tinued

Foresttypes

Locatio

nPlot

size(ha)

Tree

girth

studied

(cm)

Tree

density

(noha)

Tree

basal

area

(m2 ha)

Shanno

nindex

References

Other

coun

tries

Trop

icalrain

forests

(you

ngforests

)Ba

rrow

ColoradoIsland

Panam

a5

gt18

84ndash171

26ndash

52

mdash[17]

Trop

icalrain

forests

(old

forests

)Ba

rrow

ColoradoIsland

Panam

a50

gt18

143ndash177

43ndash5

mdash[18]

Trop

icalrain

forests

Amazon

ia3

314

1420

28ndash6

8mdash

[19]

Equatoria

linsular

forests

Easte

rnCa

rolline

Island

Panam

a50

gt314

98ndash114

17mdash

[20]

Trop

icalrain

forests

Jung

kaRe

serveMalaysia

1191

104

23mdash

[21]

Trop

icalrain

forests

Gun

ungSilamM

alaysia

004

314

513ndash1596

23ndash4

6mdash

[22]

Trop

icalmoistforests

Sing

apore

04

gt63

604

mdashmdash

[23]

Trop

icalrain

forests

Valcan

BarvaCostaRica

6gt314

391ndash617

mdashmdash

[24]

Slop

eforests

New

Caledo

nia

28

gt314

1533

49mdash

[25]

Allu

vium

forests

New

Caledo

nia

26

gt314

1183

47mdash

[25]

Equatoria

lforests

KongoIsland

mdashmdash

440ndash

553

10ndash4

5mdash

[26]

Trop

icalrain

forests

Amazon

ia3

gt314

1720

78mdash

[19]

Trop

icalseason

alrain

forests

Xishuang

bann

aCh

ina

2500

m2

15154

mdash34

[27]

Trop

icalmon

tane

rain

forests

Xishuang

bann

aCh

ina

1600

m2

15123

mdash32

[27]

Evergreenbroadleaved

forests

Xishuang

bann

aCh

ina

1200

m2

15165

mdash25

[27]

Mon

soon

forests

Xishuang

bann

aCh

ina

400m

210

150

mdash16

[27]

ldquoStudy

cond

uctedin

6different

vegetatio

ntypeso

fWestern

Ghats(N

BR)

12 ISRN Ecology

relatively undisturbed or less disturbed conditions in thestands The high annual precipitation rate and optimumtemperature of EVER may have contributed to high treegrowth rate and higher tree basal area

42 Regeneration All other vegetation types had betterregeneration than DECI In WOOD the transition rate ofstems from small girth classes to larger girth classes was lowPoor tree regeneration in DECI and WOOD can probablybe attributed to fuel wood collection frequent fires andgrazing by cattle In all forest types 29ndash47 of tree specieswere present in all three growth phases other species werepresent in either one or two growth phases Dominant speciesoccurred in all girth classes of vegetation types other thanWOOD in whichmost trees were in the smaller girth classesThere were more large trees in vegetation types like SEMIand EVER and in these sapling and seedling densities wereadequate for restocking the complement of canopy trees

Change in species composition across mature and regen-erating tree phases was more frequent in disturbed foresttypes like DECI and WOOD In some cases the dominantspecies in adult and seedling stages were quite differentin these two disturbed forest types Our results are notcongruent with observationsmade in northeastern India [39]where tree seedling survival rate increases with increasingforest disturbance We found species without regeneratingphases these are unlikely to persist Others that occurred onlyin seedling and sapling stages were new entrants to the forestspecies complement These are examples of discontinuouspopulation structures Such structures occur in a number ofother tropical countries [57ndash59] The dominant species in aforest stand is generally present in all size classes [38] Thesize class structures of trees indicate the probability of speciespersistence into the future this information is very valuablein the design of management strategies aiming to improvestand structure and species diversity Changes in speciescomposition and recruitment of new species in differentvegetation types are indicative of future species compositionin changing environments

5 Conclusions

The species diversity of trees varied across vegetation types inthe Western Ghats landscape Rarefaction curves show thatspecies diversity is highest in SEMI and EVER and lowest inWOOD while species abundance is highest in MONT Vege-tation types of study area are in heterogeneous in distributionThere were large differences in species composition of adulttrees and regenerating individuals in the disturbed vegetationtypes as compared to undisturbed stands The present studyreveals that the anthropogenic disturbance causes disruptionof forest structure and change in species composition whichultimately leads to reduction of tree species richness andabundance which are the major attributes of forests Newrecruits were found in all vegetation types indicating thattheywere not headed to extinction however disturbed standsmay move to new species compositions in the future

Acknowledgments

The authors are thankful to the Ministry of Environmentand Forests for financial support and the Vice Chancellorof University of Delhi and the Director of Kerala ForestResearch Institute for facilities provided The first authorwould like to thank Professor C R Babu for facilities andencouragement The authors are very much obliged to allmembers of the Cholanaikkan tribe who helped duringthe field survey The Kerala Forest Department provided alllogistical support for the floristic and ecological survey of theforest area (trees haminus1) in three different growth phases of sixvegetation

References

[1] M A Huston Biological Diversity The Coexistence of Species inChanging Landscapes Cambridge University Press CambridgeUK 1994

[2] T C Whitmore An Introduction to Tropical Rain ForestsOxfordUniversity Press NewYork NYUSA 2nd edition 1998

[3] M L Khan S Menon and K S Bawa ldquoEffectiveness of theprotected area network in biodiversity conservation a case-study of Meghalaya staterdquo Biodiversity and Conservation vol 6no 6 pp 853ndash868 1997

[4] C M Pringle ldquoNutrient spatial heterogeneity effects on com-munity structure physiognomy and diversity of stream algaerdquoEcology vol 71 no 3 pp 905ndash920 1990

[5] M Parviainen M Marmion M Luoto W Thuiller and RK Heikkinen ldquoUsing summed individual species models andstate-of-the-art modelling techniques to identify threatenedplant species hotspotsrdquo Biological Conservation vol 142 no 11pp 2501ndash2509 2009

[6] J S Singh S P Singh A K Saxena and Y S Ravat ldquoThe forestvegetation of Silent Valleyrdquo in Tropical Rain Forests The LeedsSymposium pp 25ndash52 1984

[7] A O Varghese ldquoAssessment of biodiversity of PepparaWildlifeSanctuary Trivandrum District Keralardquo Journal of Economicand Taxonomic Botany vol 23 pp 117ndash127 1998

[8] M A Suraj Phytosociological and vagetation mapping at chim-mony wildlife Sanctuary (Kerala) using remote sensing technique[PhD thesis] FRI University Dehradun India 1997

[9] N Parthasarathy Studies on the vacular flora structure andnutrient cycling in Kalakad Reserve Forest Western Ghats TamilNadu [PhD thesis] University of Madras Tamil Nadu India1986

[10] S N Rai and J Proctor ldquoEcological studies on four rainforests in Karnataka India environment forest structure andvegetationrdquo Journal of Vegetation Science vol 1 pp 609ndash6141986

[11] U M Chadrashekara A R R Menon K K N Nair NSasidharan and K Swarupanandan ldquoEvaluating plant diversityin different forest types of Kerala by laying out permanent sam-ple plotsrdquo KFRI Research Report 156 Kerala Forest ResearchInstitute Peechi India 1998

[12] C S Jha and J S Singh ldquoComposition and dynamics of drytropical Forest in relation to soil texturerdquo Journal of VegetationScience vol 1 no 5 pp 609ndash614 1990

[13] NVisalakshi ldquoVegetation analysis of two tropical dry evergreenforests in southern IndiardquoTropical Ecology vol 36 no 1 pp 117ndash127 1995

ISRN Ecology 13

[14] T Ganesh R Ganesan M Soubadra Devy P Davidar and K SBawa ldquoAssessment of plant biodiversity at amid-elevation ever-green forest of Kalakad-Mundanthurai Tiger Reserve WesternGhats Indiardquo Current Science vol 71 no 5 pp 379ndash392 1996

[15] S M Sundarapandian and P S Swamy ldquoForest ecosystemstructure and composition along an altitudinal gradient in theWestern Ghats South Indiardquo Journal of Tropical Forest Sciencevol 12 no 1 pp 104ndash123 2000

[16] K Swarupanandan N Sasidharan K C Chacko and SChanduBasha ldquoFloristic and ecological studies on the Sholasof Idukki Districtrdquo in Shola Forests of Kerala Environmentand Biodiverstiy K K N Nair S K Khanduri and K Bala-subramaniayan Eds pp 259ndash286 Kerala Forest DeparmentThiruvanathapuram Kerala Forest Research Institute PeechiIndia 2001

[17] R W Thorington S Tannenbaum A Tarak and R RudranldquoDistribution of trees in Baro Colorado Islands a hectaresamplerdquo in The Ecology of a Tropical Forest-Seasonal Rhythmsand Long-term Changes E G Leigh Jr A S Rand and D MWindsor Eds Smithsonian Institute Press Washington DCUSA 1982

[18] S P Hubbell and R B Foster ldquoDiversity of canopy speciesin a neotropical forest and implications for conservationrdquo inTropical Rain Forest Ecology and Management S L Sutton TCWhitmore andA C Chadwick Eds Blackwell Oxford UK1983

[19] D G Campbell D C Daly G T Prance and U N MacielldquoQuantitative ecological inventory of terra firme and varzeatropical forest on the Rio Xingu Brazilian Amazonrdquo Brittoniavol 38 no 4 pp 369ndash393 1986

[20] S Itow ldquoSpecies diversity of equatorial insular forests on Ponapeand Kosrae Micronesiardquo Ecological Research vol 1 no 2 pp223ndash227 1986

[21] C C Ho D M Newbery and M E D Poore ldquoForestcomposition and inferred dynamics in Jengka Forest ReserveMalaysiardquo Journal of Tropical Ecology vol 3 no 1 pp 25ndash561987

[22] J Proctor Y F Lee A M Langley W R C Munro and TNelson ldquoEcological studies onGunung Silam a small ultrabasicmountain Sabah Malaysiardquo Journal of Ecology vol 74 pp 455ndash463 1988

[23] F R Swan Jr ldquoTree distribution patterns in the Bukittimahnature reserve Singaporerdquo Gardens Bulletin vol 41 pp 59ndash811988

[24] A Heaney and J Proctor ldquoPreliminary studies on foreststructure and floristics on Volcan Barva Costa Ricardquo Journalof Tropical Ecology vol 6 no 3 pp 307ndash320 1990

[25] T Jaffre and J M Veillon ldquoEtude floristique et structuralede deux forets denses humides sur roches ultrabasiques enNouvelle- Caledonierdquo Bulletin du Museum National drsquoHistoireNaturelle vol 12 pp 243ndash273 1990

[26] MMosango ldquoContribution ldquoA lrsquoetude botanic biogeo 1rdquo ecosys-tem Foret en region equatorial (Ile KongoloZaire)rdquo BelgiumJournal of Botany vol 124 pp 167ndash194 1991

[27] M Cao and J Zhang ldquoTree species diversity of tropical forestvegetation in Xishuangbanna SW Chinardquo Biodiversity andConservation vol 6 no 7 pp 995ndash1006 1997

[28] C S Jha L Goparaju A Tripathi B Gharai A S Raghubanshiand J S Singh ldquoForest fragmentation and its impact onspecies diversity an analysis using remote sensing and GISrdquoBiodiversity and Conservation vol 14 no 7 pp 1681ndash1698 2005

[29] P S Roy C B S Dutt and P K Joshi ldquoTropical forest resourceassessment and monitoringrdquo Tropical Ecology vol 43 no 1 pp21ndash37 2002

[30] R Sagar A S Raghubanshi and J S Singh ldquoAsymptoticmodelsof species-area curve for measuring diversity of dry tropicalforest tree speciesrdquo Current Science vol 84 no 12 pp 1555ndash1560 2003

[31] R Sukumar H S Dattaraja H S Suresh et al ldquoLong-termmonitoring of vegetation in a tropical deciduous forest inMudumalai southern Indiardquo Current Science vol 62 pp 608ndash616 1992

[32] UMChandrashekara and P S Ramakrishnan ldquoVegetation andgap dynamics of a tropical wet evergreen forest in the WesternGhats of Kerala Indiardquo Journal of Tropical Ecology vol 10 no3 pp 337ndash354 1994

[33] T Ganesh R Ganesan M Soubadra Devy P Davidar and K SBawa ldquoAssessment of plant biodiversity at amid-elevation ever-green forest of Kalakad-Mundanthurai Tiger Reserve WesternGhats Indiardquo Current Science vol 71 no 5 pp 379ndash392 1996

[34] J P Pascal and R Pelissier ldquoStructure and floristic compositionof a tropical evergreen forest in south-west Indiardquo Journal ofTropical Ecology vol 12 no 2 pp 191ndash210 1996

[35] N Ayyappan and N Parthasarathy ldquoBiodiversity inventory oftrees in a large-scale permanent plot of tropical evergreen forestat Varagalaiar Anamalais Western Ghats Indiardquo Biodiversityand Conservation vol 8 no 11 pp 1533ndash1554 1999

[36] A Kumar B G Marcot and A Saxena ldquoTree species diversityand distribution patterns in tropical forests of Garo HillsrdquoCurrent Science vol 91 no 10 pp 1370ndash1381 2006

[37] N Parthasarathy ldquoTree diversity and distribution in undis-turbed and human-impacted sites of tropical wet evergreenforest in southern Western Ghats Indiardquo Biodiversity andConservation vol 8 no 10 pp 1365ndash1381 1999

[38] M L Khan J P N Rai and R S Tripathi ldquoPopulation structureof some tree species in disturbed and protected subtropicalforests of north-east Indiardquo Acta Oecologica vol 8 no 3 pp247ndash255 1987

[39] R S Tripathi and M L Khan ldquoRegeneration pattern andpopulation structure of trees in subtropical forest of North EastIndiardquo in Tropical Ecosystem-Ecology and Management K PSingh and J S Singh Eds pp 431ndash441 Wiley Eastern LimitedNew Delhi India 1992

[40] A E Scholl and A H Taylor ldquoRegeneration patterns in old-growth red fir-western white pine forests in the northern SierraNevada Lake Tahoe USArdquo Forest Ecology and Managementvol 235 no 1ndash3 pp 143ndash154 2006

[41] D A Clark ldquoRegeneration of canopy trees in tropical wetforestsrdquo Trends in Ecology and Evolution vol 1 no 6 pp 150ndash154 1986

[42] P C J Barker and J B Kirkpatrick ldquoPhyllocladus aspleniifoliusvariability in the population structure the regeneration nicheand dispersion patterns in Tasmanian forestsrdquo Australian Jour-nal of Botany vol 42 no 2 pp 163ndash190 1994

[43] C K Augspurger ldquoSeedling survival of tropical tree speciesinteractions of dispersal distance light-gaps and pathogensrdquoEcology vol 65 no 6 pp 1705ndash1712 1984

[44] O L Phillips ldquoLong-term environmental change in tropicalforests increasing tree turnoverrdquo Environmental Conservationvol 23 no 3 pp 235ndash248 1996

[45] Ministry of Environment and Forests ldquoPlant discoveries 2011newgenera species andnew recordsrdquo Botanical Survey of IndiaMinistry of Environment and Forests New Delhi India 2012

14 ISRN Ecology

[46] ldquoWeblink 2007rdquo httpwwwbiodiversityhotspotsorgxphot-spotshotspots by region

[47] D Mueller-Dombois and H Ellenberg Aims and Methods ofPlant Ecology John Wiley amp Sons New York NY USA 1974

[48] K K N Nair and R Jayakumar ldquoPhytogeography endemismand affinities of the flora of NewAmarambalamReserve Forestsin theWesternGhats of Indiardquo Indian Journal of Forestry vol 31pp 85ndash94 2008

[49] A E Magurran Ecological Diversity and Its MeasurementCroom Helm Ltd London UK 1988

[50] C Raunkiaer The Life Forms of Plants and Statistical PlantGeography Clarendon Press Oxford UK 1934

[51] B Rice andMWestoby ldquoPlant species richness at the 01 hectarescale in Australian vegetation compared to other continentsrdquoVegetatio vol 52 no 3 pp 129ndash140 1983

[52] SM Scheiner ldquoSix types of species-area curvesrdquoGlobal Ecologyand Biogeography vol 12 no 6 pp 441ndash447 2003

[53] H G Jones Plants and Microclimate Cambridge UniversityPress Cambridge UK 1983

[54] N C Nair The Southern Western Ghats A Biodiversity Con-servation Plan Indian National Trust for Arts and CulturalHeritage New Delhi India 1991

[55] AHGentry ldquoChanges in plant community diversity and floris-tic composition on environmental and geographical gradientrdquoAnnals of the Missouri Botanical Garden vol 75 no 1 pp 1ndash341988

[56] T CWhitmore Tropical Rain Forests of the Far East ClarendonPress Oxford UK 1984

[57] N V L Brokaw ldquoGap-phase regeneration of three pioneer treespecies in a tropical forestrdquo Journal of Ecology vol 75 no 1 pp9ndash19 1987

[58] S Itow and D Mueller-Dombois ldquoPopulation structure stand-level dieback and recovery of Scalesia pedunculata forest in theGalapagos Islandsrdquo Ecological Research vol 3 no 3 pp 333ndash339 1988

[59] T CWhitmore ldquoA review of some aspects of tropical rainforestseedling ecology with suggestions for further enquiryrdquo inEcology of Tropical Forest Tree Seedlings M D Swaine Ed pp3ndash39 UNESCOParthenon Paris France 1996

Submit your manuscripts athttpwwwhindawicom

Forestry ResearchInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Environmental and Public Health

Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

EcosystemsJournal of

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MeteorologyAdvances in

EcologyInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Marine BiologyJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom

Applied ampEnvironmentalSoil Science

Volume 2014

Advances in

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Environmental Chemistry

Atmospheric SciencesInternational Journal of

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Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Waste ManagementJournal of

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International Journal of

Geophysics

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Geological ResearchJournal of

EarthquakesJournal of

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BiodiversityInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

ScientificaHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

OceanographyInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Journal of Computational Environmental SciencesHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

ClimatologyJournal of

Page 7: Research Article Species Diversity and Tree Regeneration ...downloads.hindawi.com/archive/2013/890862.pdf · Species Diversity and Tree Regeneration Patterns in Tropical Forests of

ISRN Ecology 7

Table 3 Distribution pattern of mature and regenerating phases of trees occur in different vegetation types Regenerating species and speciesshare in all phases of trees was lower in disturbed vegetation type such as DECI and WOOD as compared to other vegetation types Percentsimilarity in species composition (using Sorenson index of similarity) of mature trees and regenerating individuals (saplings + seedlings) indifferent vegetation types of the study area and new species recruited (trees devoid of adult stage) are also shown

Vegetationtypes

Tree species occur inlowastRegeneratingspecies ()

Similarity betweenmature trees andregenerating individuals

New entryspecies ()All phases () Mature phase

only ()Regeneratingphase only ()

DECI 26 (37) 21 (30) 12 (17) 50 (70) 69 12 (17)SEMI 53 (41) 11 (9) 27 (21) 116 (91) 82 24 (18)EVER 49 (40) 11 (9) 24 (20) 111 (91) 81 23 (18)WOOD 8 (29) 8 (29) 11 (39) 20 (71) 49 10 (35)SUBM 40 (43) 4 (4) 18 (20) 87 (95) 88 20 (21)MONT 20 (47) 6 (14) 11 (26) 37 (86) 76 10 (23)lowastA number of species occur in saplings andor seedlings and these species may or may not have mature tree stage of species has been given in brackets

132 36

8

485

39

390 85

5

65

250 393

77

215 39

22073 95

57

7717

795

6971 16

395

1

10

100

1000

10000

100000

DECI SEMI EVER WOOD SUBM MONT

Den

sity

Vegetation types

Mature treesSaplingsSeedlings

Figure 4 Densities (no haminus1 in log10scale) of mature trees (ge30 cm

gbh (girth at breast height)) saplings (ge 10 lt 30 cm gbh) and seedl-ings (lt10 cm gbh) in six vegetation types occurring in the WesternGhats LSD post hoc test clarified that density of disturbed forestlike DECI and WOOD was significantly different with undisturbedvegetation type except MONT

In vegetation types influenced by disturbance and firelike WOOD 29 of species were common in all growthphases and seedling richness was very low in these types ofvegetation (Supplementary Material Appendix 2)

In vegetation types at mid elevations namely EVERand SEMI 49ndash53 of species were present in all growthphases 25ndash30 of species occurred in only one phase(Supplementary Material Appendices 3 and 4) In forestsat higher elevations namelySUBM and MONT 43 and47 of species respectively were present in all growthphases In SUBM 25 species had poor regeneration potential(Supplementary Material Appendix 5) In MONT 20 specieswere present in all growth phases and 12 had no regenerationpotential (Table 3 Supplementary Material Appendix 6)

33 Change in Species Composition among Tree Phases Over-all species richness of mature trees was higher than richnessof saplings and seedlings in all vegetation types Among the

dominant species a few trees had exceptionally large num-bers of seedling and saplings Individual trees did notcontribute equally to the seedling population or to laterrecruitment in the sapling stage Density of regeneratingindividuals (saplings + seedlings) was highest in EVER andlowest in WOOD There was significant difference in thedensity of regenerating individuals (seedling + saplings)among different vegetation types (119865

5611= 132 119875 lt 0001)

Also there was significant difference in the density of matureand regenerating phase among all vegetation types exceptWOOD (DECI 119865

1130= 117 119875 lt 0001 SEMI 119865

1269= 37

119875 lt 005 EVER 1198651255= 73 119875 lt 0008 WOOD 119865

141= 34

119875 lt 0059 SUBM 1198651201= 101 119875 lt 0002 MONT 119865

188=

51 119875 lt 0026)The overall changes in species composition from mature

stage to regenerating stage (sapling + seedling phases) ofdifferent vegetation types 21 that is 79 similarity (usingSorenson index of similarity) between mature and regenerat-ing phase In disturbed WOOD and DECI the similarity inspecies composition between mature trees and regeneratingindividuals was 49 and 69 respectively In little-disturbedvegetation types species similarity between mature trees andregenerating phases was relatively high In all the forest typesnew entry species (tree species with no adult stages) werepresent Percent of new entry species was highest in fireaffected WOOD vegetation (Table 3)

4 Discussion

41 Species Diversity Theuse of species-individuals curves inaddition to species-area curves provides a clear insight intospecies diversity More sampling area is required for speciesrich vegetation type compared to species poor one and ingeneral the minimum area varies with number of speciesfrom one vegetation type to another [51] In our data species-rich communities like SEMI and EVER seem to have lessdominance than species-poor communities However lowerrarefaction curve in MONT suggests that abundance effectmay not be the sole reason for high richness The accumu-lation of new species with increasing sampling effort canbe visualized with a species accumulation curve Increasing

8 ISRN Ecology

0

20

40

60

80

100

Frequency classes

DECI

0ndash20 21ndash40 41ndash60 61ndash80 81ndash100

Spec

ies (

)

(a)

0

20

40

60

80

100SEMI

Frequency classes0ndash20 21ndash40 41ndash60 61ndash80 81ndash100

Spec

ies (

)

(b)

0

20

40

60

80

100

EVER

Frequency classes0ndash20 21ndash40 41ndash60 61ndash80 81ndash100

Spec

ies (

)

(c)

0

20

40

60

80

100

WOOD

Frequency classes0ndash20 21ndash40 41ndash60 61ndash80 81ndash100

Spec

ies (

)

(d)

0

20

40

60

80

100

SUBM

Frequency classes0ndash20 21ndash40 41ndash60 61ndash80 81ndash100

Mature treesSaplingsSeedlings

Spec

ies (

)

(e)

0

20

40

60

80

100

MONT

Mature treesSaplingsSeedlings

Frequency classes0ndash20 21ndash40 41ndash60 61ndash80 81ndash100

Spec

ies (

)

(f)

Figure 5 Percent frequencies of trees (ge30 cm gbh) in different vegetation types Most of the species were in the lowest frequency class inall vegetation types other than MONT indicating that a few species were widely distributed most were restricted in distribution This is atypical species-abundance distribution (normal distribution) and the tree species in all the vegetation type were heterogeneous distributionin Raunkiaerrsquos sense

the area sampled increases observed species richness bothbecause more individuals get included in the sample andbecause large areas are environmentally more heterogeneousthan small areas [52] The correlation between species rich-ness and abundance suggests that process affecting change ineither richness or abundance also affects species diversity

Species richness of DECI was reduced likely due to lowrainfall and anthropogenic disturbances such as firewoodcollection and cattle grazing In fire affected WOOD grasseswere the dominant life forms these were intermingled with afew fire tolerant light demanding trees High species richnessof trees in SEMI EVER and SUBM was probably relatedto high rainfall and optimal climatic conditions (Table 2)Low temperature and high wind velocity in the MONT may

negatively impact tree growth and reduce species richnessthere DECI standswere dominated bymembers of the familyFabaceae while Euphorbiaceae and Rubiaceae dominated inEVER at mid elevations High elevation SUBM and MONTwere dominated bymembers of the Lauraceae andMyrtaceaewhich have volatile oils in their tissues that resist freezingdamage in plant cells [53]

Compared to DECI tree species diversity was very highin other forest types at higher elevations other than in thefire-affected WOOD High species diversity of SEMI is dueits transitional nature that is this vegetation type is ecotonearea suitable for both deciduous and evergreen tree species sothere is an increase in the number of species Species diversityindices for saplings were lower than those for mature trees

ISRN Ecology 9

3721 19 10 6 3 2 1 1

020406080

100DECI

Tree

s (

)

Girth classes

10ndash5

0

101ndash

150

151ndash

200

201ndash

250

251ndash

300

301ndash

350

351ndash

400

51ndash1

00

gt400

(a)

020406080

10060

20 9 3 2 2 21 1

SEMI

Tree

s (

)

Girth classes

10ndash5

0

101ndash

150

151ndash

200

201ndash

250

251ndash

300

301ndash

350

351ndash

400

51ndash1

00

gt400

(b)

020406080

10065

19 9 3 2 2 21 1

EVER

Tree

s (

)

Girth classes

10ndash5

0

101ndash

150

151ndash

200

201ndash

250

251ndash

300

301ndash

350

351ndash

400

51ndash1

00

gt400

(c)

020406080

100 96

4 0 0 0 0 0 0 0

WOOD

Tree

s (

)

Girth classes

10ndash5

0

101ndash

150

151ndash

200

201ndash

250

251ndash

300

301ndash

350

351ndash

400

51ndash1

00

gt400

(d)

020406080

10058

20 12 4 2 1 1 1 1

SUBM

Girth classes

10ndash5

0

101ndash

150

151ndash

200

201ndash

250

251ndash

300

301ndash

350

351ndash

400

Tree

s (

)

51ndash1

00

gt400

(e)

020406080

10070

243 2 1 0 0 0 0

MONT

Tree

s (

)

Girth classes

10ndash5

0

101ndash

150

151ndash

200

201ndash

250

251ndash

300

301ndash

350

351ndash

400

51ndash1

00

gt400

(f)

Figure 6 Girth frequency distributions of trees in different vegetation types of the study area Girth-size was highest in SEMI and EVER Ahigh percentage of lower girth class trees in DECI results from reduced fuel wood extraction by people of nearby areas The reverse J-shapedgbh distribution of trees indicates evolving or expanding population

and seedlings in DECI is due to overharvesting of saplingsfor firewood The lowest species diversity value in WOODindicates low species richness and dominance of one or twospecies in the tree community In the present study Shannonindex values for tree species are similar to values for othertropical forests of the world (Table 4) However detailedcomparisons with other studies are inadvisable because oflarge differences in sample size standard girth parametersand environmental conditions

Density and frequency distributions of trees contributeto the structure of tropical forests Tree density in DECI wasmuch lower than that of other forest types perhaps due to lowrainfall and anthropogenic disturbances Density was least inthe fire-affected WOOD Sapling densities were elevated inSEMI and EVER Late secondary successional species werewell represented in the sapling population of EVER whichmay be indicative of recent natural disturbances in this foresttype that promoted regeneration of late secondary speciesMONT had high sapling density due to the stunted nature oftrees caused by very low temperature and high wind velocityprevalent there [54]

Densities of trees in the study area were similar toestimates from tropical forests within India and other tropicalregions (Table 4) In tropical forests outside India there ismuch variation in the densities of trees gt30 cm gbh (98ndash1930 trees haminus1) especially in Amazonian forests In theNeotropics maximum species richness of tree individualsgt10 cm gbh reaches 300 haminus1 [55] In South-East Asia thehighest richness is 225 haminus1 [56]

In the present studymost of the species were in frequencyclass 0ndash20 and fewest were in frequency class 80ndash100The frequency distribution of tree species suggested thatmostof them had low frequency as would be expected in typicalspecies-abundance distribution A plant species should beconsidered homogeneously distributed when the numbersof individuals are the same in all parts of a community[50] Hence tree species in all the vegetation types of thestudy area were heterogeneously distributed Girth classfrequency distributions of most species in vegetation typeswe studied fit ldquoreverse Jrdquo-shaped patterns with most trees insmaller girth classes and few old trees Vegetation types otherthan WOOD fit negative exponential patterns indicative of

10 ISRN Ecology

Table4Ve

getatio

nparameterso

fforestcom

mun

ities

inthetropics

ofIndiaa

ndotherc

ountrie

s

Foresttypes

Locatio

nPlot

size(ha)

Tree

girth

studied

(cm)

Tree

density

(noha)

Tree

basal

area

(m2 ha)

Shanno

nindex

References

Presentstudy

DEC

IWestern

Ghats(N

BR)

4ha

ge30

cm132

234

279

Present

study

SEMI

ldquo4ha

ge30

cm368

457

367

ldquo

EVER

ldquo4ha

ge30

cm485

480

334

ldquo

WOOD

ldquo3ha

ge30

cm39

069

221

ldquo

SUBM

ldquo4ha

ge30

cm390

365

326

ldquo

MONT

ldquo4ha

ge30

cm855

309

321

ldquo

India

Evergreenforests

Silent

valleyWestern

Ghat

mdashge315

620ndash

709

29ndash103

mdash[6]

Moistdecidu

ousforests

Pepp

araWGhats

mdashge30

590ndash

740

13ndash51

2ndash33

[7]

Moistdecidu

ousforests

Chim

mon

yWestern

Ghats

mdashge30

558

3719

ndash24

[8]

Semievergreen

forests

Pepp

araWestern

Ghats

mdashge30

670ndash

940

45ndash6

229

[7]

Semievergreen

forests

Chim

mon

yWestern

Ghats

mdashge30

728

4727ndash32

[8]

Scrubjung

leto

wetevergreenforests

Kalakk

adRF

Western

Ghats

02

gt20

320ndash

1260

18ndash107

mdash[9]

Evergreenforests

Karnataka

044

mdash44

6ndash1386

33ndash4

8mdash

[10]

Evergreenforests

Pepp

ara

mdashge30

860ndash

1370

7633

[7]

Evergreenforests

NelliampathiWestern

Ghats

mdashge30

mdash498

3ndash37

[11]

Dry

tropicalforests

Vind

hyar

egion

mdashgt30

294ndash

559

7ndash23

mdash[12]

Dry

evergreenforests

Puthup

etSacred

GroveC

orom

andel

coast

02

gt20

280

11mdash

[13]

Trop

icalwe

tevergreen

forests

Kalakk

ad-M

undanthu

raiT

iger

Reserve

Western

Ghats

050

gt30

315ndash418

54ndash8

4mdash

[14]

Trop

icalwe

tevergreen

forests

KodayarWestern

Ghats

050

gt30

352ndash117

328ndash81

mdash[15]

Subtropicalh

illforests

Pepp

araWestern

Ghats

mdashge30

1580ndash1930

27ndash34

27

[7]

Mon

tane

temperateforests

Mannavanshola

mdashge30

566

52399

[16]

ISRN Ecology 11

Table4Con

tinued

Foresttypes

Locatio

nPlot

size(ha)

Tree

girth

studied

(cm)

Tree

density

(noha)

Tree

basal

area

(m2 ha)

Shanno

nindex

References

Other

coun

tries

Trop

icalrain

forests

(you

ngforests

)Ba

rrow

ColoradoIsland

Panam

a5

gt18

84ndash171

26ndash

52

mdash[17]

Trop

icalrain

forests

(old

forests

)Ba

rrow

ColoradoIsland

Panam

a50

gt18

143ndash177

43ndash5

mdash[18]

Trop

icalrain

forests

Amazon

ia3

314

1420

28ndash6

8mdash

[19]

Equatoria

linsular

forests

Easte

rnCa

rolline

Island

Panam

a50

gt314

98ndash114

17mdash

[20]

Trop

icalrain

forests

Jung

kaRe

serveMalaysia

1191

104

23mdash

[21]

Trop

icalrain

forests

Gun

ungSilamM

alaysia

004

314

513ndash1596

23ndash4

6mdash

[22]

Trop

icalmoistforests

Sing

apore

04

gt63

604

mdashmdash

[23]

Trop

icalrain

forests

Valcan

BarvaCostaRica

6gt314

391ndash617

mdashmdash

[24]

Slop

eforests

New

Caledo

nia

28

gt314

1533

49mdash

[25]

Allu

vium

forests

New

Caledo

nia

26

gt314

1183

47mdash

[25]

Equatoria

lforests

KongoIsland

mdashmdash

440ndash

553

10ndash4

5mdash

[26]

Trop

icalrain

forests

Amazon

ia3

gt314

1720

78mdash

[19]

Trop

icalseason

alrain

forests

Xishuang

bann

aCh

ina

2500

m2

15154

mdash34

[27]

Trop

icalmon

tane

rain

forests

Xishuang

bann

aCh

ina

1600

m2

15123

mdash32

[27]

Evergreenbroadleaved

forests

Xishuang

bann

aCh

ina

1200

m2

15165

mdash25

[27]

Mon

soon

forests

Xishuang

bann

aCh

ina

400m

210

150

mdash16

[27]

ldquoStudy

cond

uctedin

6different

vegetatio

ntypeso

fWestern

Ghats(N

BR)

12 ISRN Ecology

relatively undisturbed or less disturbed conditions in thestands The high annual precipitation rate and optimumtemperature of EVER may have contributed to high treegrowth rate and higher tree basal area

42 Regeneration All other vegetation types had betterregeneration than DECI In WOOD the transition rate ofstems from small girth classes to larger girth classes was lowPoor tree regeneration in DECI and WOOD can probablybe attributed to fuel wood collection frequent fires andgrazing by cattle In all forest types 29ndash47 of tree specieswere present in all three growth phases other species werepresent in either one or two growth phases Dominant speciesoccurred in all girth classes of vegetation types other thanWOOD in whichmost trees were in the smaller girth classesThere were more large trees in vegetation types like SEMIand EVER and in these sapling and seedling densities wereadequate for restocking the complement of canopy trees

Change in species composition across mature and regen-erating tree phases was more frequent in disturbed foresttypes like DECI and WOOD In some cases the dominantspecies in adult and seedling stages were quite differentin these two disturbed forest types Our results are notcongruent with observationsmade in northeastern India [39]where tree seedling survival rate increases with increasingforest disturbance We found species without regeneratingphases these are unlikely to persist Others that occurred onlyin seedling and sapling stages were new entrants to the forestspecies complement These are examples of discontinuouspopulation structures Such structures occur in a number ofother tropical countries [57ndash59] The dominant species in aforest stand is generally present in all size classes [38] Thesize class structures of trees indicate the probability of speciespersistence into the future this information is very valuablein the design of management strategies aiming to improvestand structure and species diversity Changes in speciescomposition and recruitment of new species in differentvegetation types are indicative of future species compositionin changing environments

5 Conclusions

The species diversity of trees varied across vegetation types inthe Western Ghats landscape Rarefaction curves show thatspecies diversity is highest in SEMI and EVER and lowest inWOOD while species abundance is highest in MONT Vege-tation types of study area are in heterogeneous in distributionThere were large differences in species composition of adulttrees and regenerating individuals in the disturbed vegetationtypes as compared to undisturbed stands The present studyreveals that the anthropogenic disturbance causes disruptionof forest structure and change in species composition whichultimately leads to reduction of tree species richness andabundance which are the major attributes of forests Newrecruits were found in all vegetation types indicating thattheywere not headed to extinction however disturbed standsmay move to new species compositions in the future

Acknowledgments

The authors are thankful to the Ministry of Environmentand Forests for financial support and the Vice Chancellorof University of Delhi and the Director of Kerala ForestResearch Institute for facilities provided The first authorwould like to thank Professor C R Babu for facilities andencouragement The authors are very much obliged to allmembers of the Cholanaikkan tribe who helped duringthe field survey The Kerala Forest Department provided alllogistical support for the floristic and ecological survey of theforest area (trees haminus1) in three different growth phases of sixvegetation

References

[1] M A Huston Biological Diversity The Coexistence of Species inChanging Landscapes Cambridge University Press CambridgeUK 1994

[2] T C Whitmore An Introduction to Tropical Rain ForestsOxfordUniversity Press NewYork NYUSA 2nd edition 1998

[3] M L Khan S Menon and K S Bawa ldquoEffectiveness of theprotected area network in biodiversity conservation a case-study of Meghalaya staterdquo Biodiversity and Conservation vol 6no 6 pp 853ndash868 1997

[4] C M Pringle ldquoNutrient spatial heterogeneity effects on com-munity structure physiognomy and diversity of stream algaerdquoEcology vol 71 no 3 pp 905ndash920 1990

[5] M Parviainen M Marmion M Luoto W Thuiller and RK Heikkinen ldquoUsing summed individual species models andstate-of-the-art modelling techniques to identify threatenedplant species hotspotsrdquo Biological Conservation vol 142 no 11pp 2501ndash2509 2009

[6] J S Singh S P Singh A K Saxena and Y S Ravat ldquoThe forestvegetation of Silent Valleyrdquo in Tropical Rain Forests The LeedsSymposium pp 25ndash52 1984

[7] A O Varghese ldquoAssessment of biodiversity of PepparaWildlifeSanctuary Trivandrum District Keralardquo Journal of Economicand Taxonomic Botany vol 23 pp 117ndash127 1998

[8] M A Suraj Phytosociological and vagetation mapping at chim-mony wildlife Sanctuary (Kerala) using remote sensing technique[PhD thesis] FRI University Dehradun India 1997

[9] N Parthasarathy Studies on the vacular flora structure andnutrient cycling in Kalakad Reserve Forest Western Ghats TamilNadu [PhD thesis] University of Madras Tamil Nadu India1986

[10] S N Rai and J Proctor ldquoEcological studies on four rainforests in Karnataka India environment forest structure andvegetationrdquo Journal of Vegetation Science vol 1 pp 609ndash6141986

[11] U M Chadrashekara A R R Menon K K N Nair NSasidharan and K Swarupanandan ldquoEvaluating plant diversityin different forest types of Kerala by laying out permanent sam-ple plotsrdquo KFRI Research Report 156 Kerala Forest ResearchInstitute Peechi India 1998

[12] C S Jha and J S Singh ldquoComposition and dynamics of drytropical Forest in relation to soil texturerdquo Journal of VegetationScience vol 1 no 5 pp 609ndash614 1990

[13] NVisalakshi ldquoVegetation analysis of two tropical dry evergreenforests in southern IndiardquoTropical Ecology vol 36 no 1 pp 117ndash127 1995

ISRN Ecology 13

[14] T Ganesh R Ganesan M Soubadra Devy P Davidar and K SBawa ldquoAssessment of plant biodiversity at amid-elevation ever-green forest of Kalakad-Mundanthurai Tiger Reserve WesternGhats Indiardquo Current Science vol 71 no 5 pp 379ndash392 1996

[15] S M Sundarapandian and P S Swamy ldquoForest ecosystemstructure and composition along an altitudinal gradient in theWestern Ghats South Indiardquo Journal of Tropical Forest Sciencevol 12 no 1 pp 104ndash123 2000

[16] K Swarupanandan N Sasidharan K C Chacko and SChanduBasha ldquoFloristic and ecological studies on the Sholasof Idukki Districtrdquo in Shola Forests of Kerala Environmentand Biodiverstiy K K N Nair S K Khanduri and K Bala-subramaniayan Eds pp 259ndash286 Kerala Forest DeparmentThiruvanathapuram Kerala Forest Research Institute PeechiIndia 2001

[17] R W Thorington S Tannenbaum A Tarak and R RudranldquoDistribution of trees in Baro Colorado Islands a hectaresamplerdquo in The Ecology of a Tropical Forest-Seasonal Rhythmsand Long-term Changes E G Leigh Jr A S Rand and D MWindsor Eds Smithsonian Institute Press Washington DCUSA 1982

[18] S P Hubbell and R B Foster ldquoDiversity of canopy speciesin a neotropical forest and implications for conservationrdquo inTropical Rain Forest Ecology and Management S L Sutton TCWhitmore andA C Chadwick Eds Blackwell Oxford UK1983

[19] D G Campbell D C Daly G T Prance and U N MacielldquoQuantitative ecological inventory of terra firme and varzeatropical forest on the Rio Xingu Brazilian Amazonrdquo Brittoniavol 38 no 4 pp 369ndash393 1986

[20] S Itow ldquoSpecies diversity of equatorial insular forests on Ponapeand Kosrae Micronesiardquo Ecological Research vol 1 no 2 pp223ndash227 1986

[21] C C Ho D M Newbery and M E D Poore ldquoForestcomposition and inferred dynamics in Jengka Forest ReserveMalaysiardquo Journal of Tropical Ecology vol 3 no 1 pp 25ndash561987

[22] J Proctor Y F Lee A M Langley W R C Munro and TNelson ldquoEcological studies onGunung Silam a small ultrabasicmountain Sabah Malaysiardquo Journal of Ecology vol 74 pp 455ndash463 1988

[23] F R Swan Jr ldquoTree distribution patterns in the Bukittimahnature reserve Singaporerdquo Gardens Bulletin vol 41 pp 59ndash811988

[24] A Heaney and J Proctor ldquoPreliminary studies on foreststructure and floristics on Volcan Barva Costa Ricardquo Journalof Tropical Ecology vol 6 no 3 pp 307ndash320 1990

[25] T Jaffre and J M Veillon ldquoEtude floristique et structuralede deux forets denses humides sur roches ultrabasiques enNouvelle- Caledonierdquo Bulletin du Museum National drsquoHistoireNaturelle vol 12 pp 243ndash273 1990

[26] MMosango ldquoContribution ldquoA lrsquoetude botanic biogeo 1rdquo ecosys-tem Foret en region equatorial (Ile KongoloZaire)rdquo BelgiumJournal of Botany vol 124 pp 167ndash194 1991

[27] M Cao and J Zhang ldquoTree species diversity of tropical forestvegetation in Xishuangbanna SW Chinardquo Biodiversity andConservation vol 6 no 7 pp 995ndash1006 1997

[28] C S Jha L Goparaju A Tripathi B Gharai A S Raghubanshiand J S Singh ldquoForest fragmentation and its impact onspecies diversity an analysis using remote sensing and GISrdquoBiodiversity and Conservation vol 14 no 7 pp 1681ndash1698 2005

[29] P S Roy C B S Dutt and P K Joshi ldquoTropical forest resourceassessment and monitoringrdquo Tropical Ecology vol 43 no 1 pp21ndash37 2002

[30] R Sagar A S Raghubanshi and J S Singh ldquoAsymptoticmodelsof species-area curve for measuring diversity of dry tropicalforest tree speciesrdquo Current Science vol 84 no 12 pp 1555ndash1560 2003

[31] R Sukumar H S Dattaraja H S Suresh et al ldquoLong-termmonitoring of vegetation in a tropical deciduous forest inMudumalai southern Indiardquo Current Science vol 62 pp 608ndash616 1992

[32] UMChandrashekara and P S Ramakrishnan ldquoVegetation andgap dynamics of a tropical wet evergreen forest in the WesternGhats of Kerala Indiardquo Journal of Tropical Ecology vol 10 no3 pp 337ndash354 1994

[33] T Ganesh R Ganesan M Soubadra Devy P Davidar and K SBawa ldquoAssessment of plant biodiversity at amid-elevation ever-green forest of Kalakad-Mundanthurai Tiger Reserve WesternGhats Indiardquo Current Science vol 71 no 5 pp 379ndash392 1996

[34] J P Pascal and R Pelissier ldquoStructure and floristic compositionof a tropical evergreen forest in south-west Indiardquo Journal ofTropical Ecology vol 12 no 2 pp 191ndash210 1996

[35] N Ayyappan and N Parthasarathy ldquoBiodiversity inventory oftrees in a large-scale permanent plot of tropical evergreen forestat Varagalaiar Anamalais Western Ghats Indiardquo Biodiversityand Conservation vol 8 no 11 pp 1533ndash1554 1999

[36] A Kumar B G Marcot and A Saxena ldquoTree species diversityand distribution patterns in tropical forests of Garo HillsrdquoCurrent Science vol 91 no 10 pp 1370ndash1381 2006

[37] N Parthasarathy ldquoTree diversity and distribution in undis-turbed and human-impacted sites of tropical wet evergreenforest in southern Western Ghats Indiardquo Biodiversity andConservation vol 8 no 10 pp 1365ndash1381 1999

[38] M L Khan J P N Rai and R S Tripathi ldquoPopulation structureof some tree species in disturbed and protected subtropicalforests of north-east Indiardquo Acta Oecologica vol 8 no 3 pp247ndash255 1987

[39] R S Tripathi and M L Khan ldquoRegeneration pattern andpopulation structure of trees in subtropical forest of North EastIndiardquo in Tropical Ecosystem-Ecology and Management K PSingh and J S Singh Eds pp 431ndash441 Wiley Eastern LimitedNew Delhi India 1992

[40] A E Scholl and A H Taylor ldquoRegeneration patterns in old-growth red fir-western white pine forests in the northern SierraNevada Lake Tahoe USArdquo Forest Ecology and Managementvol 235 no 1ndash3 pp 143ndash154 2006

[41] D A Clark ldquoRegeneration of canopy trees in tropical wetforestsrdquo Trends in Ecology and Evolution vol 1 no 6 pp 150ndash154 1986

[42] P C J Barker and J B Kirkpatrick ldquoPhyllocladus aspleniifoliusvariability in the population structure the regeneration nicheand dispersion patterns in Tasmanian forestsrdquo Australian Jour-nal of Botany vol 42 no 2 pp 163ndash190 1994

[43] C K Augspurger ldquoSeedling survival of tropical tree speciesinteractions of dispersal distance light-gaps and pathogensrdquoEcology vol 65 no 6 pp 1705ndash1712 1984

[44] O L Phillips ldquoLong-term environmental change in tropicalforests increasing tree turnoverrdquo Environmental Conservationvol 23 no 3 pp 235ndash248 1996

[45] Ministry of Environment and Forests ldquoPlant discoveries 2011newgenera species andnew recordsrdquo Botanical Survey of IndiaMinistry of Environment and Forests New Delhi India 2012

14 ISRN Ecology

[46] ldquoWeblink 2007rdquo httpwwwbiodiversityhotspotsorgxphot-spotshotspots by region

[47] D Mueller-Dombois and H Ellenberg Aims and Methods ofPlant Ecology John Wiley amp Sons New York NY USA 1974

[48] K K N Nair and R Jayakumar ldquoPhytogeography endemismand affinities of the flora of NewAmarambalamReserve Forestsin theWesternGhats of Indiardquo Indian Journal of Forestry vol 31pp 85ndash94 2008

[49] A E Magurran Ecological Diversity and Its MeasurementCroom Helm Ltd London UK 1988

[50] C Raunkiaer The Life Forms of Plants and Statistical PlantGeography Clarendon Press Oxford UK 1934

[51] B Rice andMWestoby ldquoPlant species richness at the 01 hectarescale in Australian vegetation compared to other continentsrdquoVegetatio vol 52 no 3 pp 129ndash140 1983

[52] SM Scheiner ldquoSix types of species-area curvesrdquoGlobal Ecologyand Biogeography vol 12 no 6 pp 441ndash447 2003

[53] H G Jones Plants and Microclimate Cambridge UniversityPress Cambridge UK 1983

[54] N C Nair The Southern Western Ghats A Biodiversity Con-servation Plan Indian National Trust for Arts and CulturalHeritage New Delhi India 1991

[55] AHGentry ldquoChanges in plant community diversity and floris-tic composition on environmental and geographical gradientrdquoAnnals of the Missouri Botanical Garden vol 75 no 1 pp 1ndash341988

[56] T CWhitmore Tropical Rain Forests of the Far East ClarendonPress Oxford UK 1984

[57] N V L Brokaw ldquoGap-phase regeneration of three pioneer treespecies in a tropical forestrdquo Journal of Ecology vol 75 no 1 pp9ndash19 1987

[58] S Itow and D Mueller-Dombois ldquoPopulation structure stand-level dieback and recovery of Scalesia pedunculata forest in theGalapagos Islandsrdquo Ecological Research vol 3 no 3 pp 333ndash339 1988

[59] T CWhitmore ldquoA review of some aspects of tropical rainforestseedling ecology with suggestions for further enquiryrdquo inEcology of Tropical Forest Tree Seedlings M D Swaine Ed pp3ndash39 UNESCOParthenon Paris France 1996

Submit your manuscripts athttpwwwhindawicom

Forestry ResearchInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Environmental and Public Health

Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

EcosystemsJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

MeteorologyAdvances in

EcologyInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Marine BiologyJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom

Applied ampEnvironmentalSoil Science

Volume 2014

Advances in

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Environmental Chemistry

Atmospheric SciencesInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Waste ManagementJournal of

Hindawi Publishing Corporation httpwwwhindawicom Volume 2014

International Journal of

Geophysics

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Geological ResearchJournal of

EarthquakesJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

BiodiversityInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

ScientificaHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

OceanographyInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Journal of Computational Environmental SciencesHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

ClimatologyJournal of

Page 8: Research Article Species Diversity and Tree Regeneration ...downloads.hindawi.com/archive/2013/890862.pdf · Species Diversity and Tree Regeneration Patterns in Tropical Forests of

8 ISRN Ecology

0

20

40

60

80

100

Frequency classes

DECI

0ndash20 21ndash40 41ndash60 61ndash80 81ndash100

Spec

ies (

)

(a)

0

20

40

60

80

100SEMI

Frequency classes0ndash20 21ndash40 41ndash60 61ndash80 81ndash100

Spec

ies (

)

(b)

0

20

40

60

80

100

EVER

Frequency classes0ndash20 21ndash40 41ndash60 61ndash80 81ndash100

Spec

ies (

)

(c)

0

20

40

60

80

100

WOOD

Frequency classes0ndash20 21ndash40 41ndash60 61ndash80 81ndash100

Spec

ies (

)

(d)

0

20

40

60

80

100

SUBM

Frequency classes0ndash20 21ndash40 41ndash60 61ndash80 81ndash100

Mature treesSaplingsSeedlings

Spec

ies (

)

(e)

0

20

40

60

80

100

MONT

Mature treesSaplingsSeedlings

Frequency classes0ndash20 21ndash40 41ndash60 61ndash80 81ndash100

Spec

ies (

)

(f)

Figure 5 Percent frequencies of trees (ge30 cm gbh) in different vegetation types Most of the species were in the lowest frequency class inall vegetation types other than MONT indicating that a few species were widely distributed most were restricted in distribution This is atypical species-abundance distribution (normal distribution) and the tree species in all the vegetation type were heterogeneous distributionin Raunkiaerrsquos sense

the area sampled increases observed species richness bothbecause more individuals get included in the sample andbecause large areas are environmentally more heterogeneousthan small areas [52] The correlation between species rich-ness and abundance suggests that process affecting change ineither richness or abundance also affects species diversity

Species richness of DECI was reduced likely due to lowrainfall and anthropogenic disturbances such as firewoodcollection and cattle grazing In fire affected WOOD grasseswere the dominant life forms these were intermingled with afew fire tolerant light demanding trees High species richnessof trees in SEMI EVER and SUBM was probably relatedto high rainfall and optimal climatic conditions (Table 2)Low temperature and high wind velocity in the MONT may

negatively impact tree growth and reduce species richnessthere DECI standswere dominated bymembers of the familyFabaceae while Euphorbiaceae and Rubiaceae dominated inEVER at mid elevations High elevation SUBM and MONTwere dominated bymembers of the Lauraceae andMyrtaceaewhich have volatile oils in their tissues that resist freezingdamage in plant cells [53]

Compared to DECI tree species diversity was very highin other forest types at higher elevations other than in thefire-affected WOOD High species diversity of SEMI is dueits transitional nature that is this vegetation type is ecotonearea suitable for both deciduous and evergreen tree species sothere is an increase in the number of species Species diversityindices for saplings were lower than those for mature trees

ISRN Ecology 9

3721 19 10 6 3 2 1 1

020406080

100DECI

Tree

s (

)

Girth classes

10ndash5

0

101ndash

150

151ndash

200

201ndash

250

251ndash

300

301ndash

350

351ndash

400

51ndash1

00

gt400

(a)

020406080

10060

20 9 3 2 2 21 1

SEMI

Tree

s (

)

Girth classes

10ndash5

0

101ndash

150

151ndash

200

201ndash

250

251ndash

300

301ndash

350

351ndash

400

51ndash1

00

gt400

(b)

020406080

10065

19 9 3 2 2 21 1

EVER

Tree

s (

)

Girth classes

10ndash5

0

101ndash

150

151ndash

200

201ndash

250

251ndash

300

301ndash

350

351ndash

400

51ndash1

00

gt400

(c)

020406080

100 96

4 0 0 0 0 0 0 0

WOOD

Tree

s (

)

Girth classes

10ndash5

0

101ndash

150

151ndash

200

201ndash

250

251ndash

300

301ndash

350

351ndash

400

51ndash1

00

gt400

(d)

020406080

10058

20 12 4 2 1 1 1 1

SUBM

Girth classes

10ndash5

0

101ndash

150

151ndash

200

201ndash

250

251ndash

300

301ndash

350

351ndash

400

Tree

s (

)

51ndash1

00

gt400

(e)

020406080

10070

243 2 1 0 0 0 0

MONT

Tree

s (

)

Girth classes

10ndash5

0

101ndash

150

151ndash

200

201ndash

250

251ndash

300

301ndash

350

351ndash

400

51ndash1

00

gt400

(f)

Figure 6 Girth frequency distributions of trees in different vegetation types of the study area Girth-size was highest in SEMI and EVER Ahigh percentage of lower girth class trees in DECI results from reduced fuel wood extraction by people of nearby areas The reverse J-shapedgbh distribution of trees indicates evolving or expanding population

and seedlings in DECI is due to overharvesting of saplingsfor firewood The lowest species diversity value in WOODindicates low species richness and dominance of one or twospecies in the tree community In the present study Shannonindex values for tree species are similar to values for othertropical forests of the world (Table 4) However detailedcomparisons with other studies are inadvisable because oflarge differences in sample size standard girth parametersand environmental conditions

Density and frequency distributions of trees contributeto the structure of tropical forests Tree density in DECI wasmuch lower than that of other forest types perhaps due to lowrainfall and anthropogenic disturbances Density was least inthe fire-affected WOOD Sapling densities were elevated inSEMI and EVER Late secondary successional species werewell represented in the sapling population of EVER whichmay be indicative of recent natural disturbances in this foresttype that promoted regeneration of late secondary speciesMONT had high sapling density due to the stunted nature oftrees caused by very low temperature and high wind velocityprevalent there [54]

Densities of trees in the study area were similar toestimates from tropical forests within India and other tropicalregions (Table 4) In tropical forests outside India there ismuch variation in the densities of trees gt30 cm gbh (98ndash1930 trees haminus1) especially in Amazonian forests In theNeotropics maximum species richness of tree individualsgt10 cm gbh reaches 300 haminus1 [55] In South-East Asia thehighest richness is 225 haminus1 [56]

In the present studymost of the species were in frequencyclass 0ndash20 and fewest were in frequency class 80ndash100The frequency distribution of tree species suggested thatmostof them had low frequency as would be expected in typicalspecies-abundance distribution A plant species should beconsidered homogeneously distributed when the numbersof individuals are the same in all parts of a community[50] Hence tree species in all the vegetation types of thestudy area were heterogeneously distributed Girth classfrequency distributions of most species in vegetation typeswe studied fit ldquoreverse Jrdquo-shaped patterns with most trees insmaller girth classes and few old trees Vegetation types otherthan WOOD fit negative exponential patterns indicative of

10 ISRN Ecology

Table4Ve

getatio

nparameterso

fforestcom

mun

ities

inthetropics

ofIndiaa

ndotherc

ountrie

s

Foresttypes

Locatio

nPlot

size(ha)

Tree

girth

studied

(cm)

Tree

density

(noha)

Tree

basal

area

(m2 ha)

Shanno

nindex

References

Presentstudy

DEC

IWestern

Ghats(N

BR)

4ha

ge30

cm132

234

279

Present

study

SEMI

ldquo4ha

ge30

cm368

457

367

ldquo

EVER

ldquo4ha

ge30

cm485

480

334

ldquo

WOOD

ldquo3ha

ge30

cm39

069

221

ldquo

SUBM

ldquo4ha

ge30

cm390

365

326

ldquo

MONT

ldquo4ha

ge30

cm855

309

321

ldquo

India

Evergreenforests

Silent

valleyWestern

Ghat

mdashge315

620ndash

709

29ndash103

mdash[6]

Moistdecidu

ousforests

Pepp

araWGhats

mdashge30

590ndash

740

13ndash51

2ndash33

[7]

Moistdecidu

ousforests

Chim

mon

yWestern

Ghats

mdashge30

558

3719

ndash24

[8]

Semievergreen

forests

Pepp

araWestern

Ghats

mdashge30

670ndash

940

45ndash6

229

[7]

Semievergreen

forests

Chim

mon

yWestern

Ghats

mdashge30

728

4727ndash32

[8]

Scrubjung

leto

wetevergreenforests

Kalakk

adRF

Western

Ghats

02

gt20

320ndash

1260

18ndash107

mdash[9]

Evergreenforests

Karnataka

044

mdash44

6ndash1386

33ndash4

8mdash

[10]

Evergreenforests

Pepp

ara

mdashge30

860ndash

1370

7633

[7]

Evergreenforests

NelliampathiWestern

Ghats

mdashge30

mdash498

3ndash37

[11]

Dry

tropicalforests

Vind

hyar

egion

mdashgt30

294ndash

559

7ndash23

mdash[12]

Dry

evergreenforests

Puthup

etSacred

GroveC

orom

andel

coast

02

gt20

280

11mdash

[13]

Trop

icalwe

tevergreen

forests

Kalakk

ad-M

undanthu

raiT

iger

Reserve

Western

Ghats

050

gt30

315ndash418

54ndash8

4mdash

[14]

Trop

icalwe

tevergreen

forests

KodayarWestern

Ghats

050

gt30

352ndash117

328ndash81

mdash[15]

Subtropicalh

illforests

Pepp

araWestern

Ghats

mdashge30

1580ndash1930

27ndash34

27

[7]

Mon

tane

temperateforests

Mannavanshola

mdashge30

566

52399

[16]

ISRN Ecology 11

Table4Con

tinued

Foresttypes

Locatio

nPlot

size(ha)

Tree

girth

studied

(cm)

Tree

density

(noha)

Tree

basal

area

(m2 ha)

Shanno

nindex

References

Other

coun

tries

Trop

icalrain

forests

(you

ngforests

)Ba

rrow

ColoradoIsland

Panam

a5

gt18

84ndash171

26ndash

52

mdash[17]

Trop

icalrain

forests

(old

forests

)Ba

rrow

ColoradoIsland

Panam

a50

gt18

143ndash177

43ndash5

mdash[18]

Trop

icalrain

forests

Amazon

ia3

314

1420

28ndash6

8mdash

[19]

Equatoria

linsular

forests

Easte

rnCa

rolline

Island

Panam

a50

gt314

98ndash114

17mdash

[20]

Trop

icalrain

forests

Jung

kaRe

serveMalaysia

1191

104

23mdash

[21]

Trop

icalrain

forests

Gun

ungSilamM

alaysia

004

314

513ndash1596

23ndash4

6mdash

[22]

Trop

icalmoistforests

Sing

apore

04

gt63

604

mdashmdash

[23]

Trop

icalrain

forests

Valcan

BarvaCostaRica

6gt314

391ndash617

mdashmdash

[24]

Slop

eforests

New

Caledo

nia

28

gt314

1533

49mdash

[25]

Allu

vium

forests

New

Caledo

nia

26

gt314

1183

47mdash

[25]

Equatoria

lforests

KongoIsland

mdashmdash

440ndash

553

10ndash4

5mdash

[26]

Trop

icalrain

forests

Amazon

ia3

gt314

1720

78mdash

[19]

Trop

icalseason

alrain

forests

Xishuang

bann

aCh

ina

2500

m2

15154

mdash34

[27]

Trop

icalmon

tane

rain

forests

Xishuang

bann

aCh

ina

1600

m2

15123

mdash32

[27]

Evergreenbroadleaved

forests

Xishuang

bann

aCh

ina

1200

m2

15165

mdash25

[27]

Mon

soon

forests

Xishuang

bann

aCh

ina

400m

210

150

mdash16

[27]

ldquoStudy

cond

uctedin

6different

vegetatio

ntypeso

fWestern

Ghats(N

BR)

12 ISRN Ecology

relatively undisturbed or less disturbed conditions in thestands The high annual precipitation rate and optimumtemperature of EVER may have contributed to high treegrowth rate and higher tree basal area

42 Regeneration All other vegetation types had betterregeneration than DECI In WOOD the transition rate ofstems from small girth classes to larger girth classes was lowPoor tree regeneration in DECI and WOOD can probablybe attributed to fuel wood collection frequent fires andgrazing by cattle In all forest types 29ndash47 of tree specieswere present in all three growth phases other species werepresent in either one or two growth phases Dominant speciesoccurred in all girth classes of vegetation types other thanWOOD in whichmost trees were in the smaller girth classesThere were more large trees in vegetation types like SEMIand EVER and in these sapling and seedling densities wereadequate for restocking the complement of canopy trees

Change in species composition across mature and regen-erating tree phases was more frequent in disturbed foresttypes like DECI and WOOD In some cases the dominantspecies in adult and seedling stages were quite differentin these two disturbed forest types Our results are notcongruent with observationsmade in northeastern India [39]where tree seedling survival rate increases with increasingforest disturbance We found species without regeneratingphases these are unlikely to persist Others that occurred onlyin seedling and sapling stages were new entrants to the forestspecies complement These are examples of discontinuouspopulation structures Such structures occur in a number ofother tropical countries [57ndash59] The dominant species in aforest stand is generally present in all size classes [38] Thesize class structures of trees indicate the probability of speciespersistence into the future this information is very valuablein the design of management strategies aiming to improvestand structure and species diversity Changes in speciescomposition and recruitment of new species in differentvegetation types are indicative of future species compositionin changing environments

5 Conclusions

The species diversity of trees varied across vegetation types inthe Western Ghats landscape Rarefaction curves show thatspecies diversity is highest in SEMI and EVER and lowest inWOOD while species abundance is highest in MONT Vege-tation types of study area are in heterogeneous in distributionThere were large differences in species composition of adulttrees and regenerating individuals in the disturbed vegetationtypes as compared to undisturbed stands The present studyreveals that the anthropogenic disturbance causes disruptionof forest structure and change in species composition whichultimately leads to reduction of tree species richness andabundance which are the major attributes of forests Newrecruits were found in all vegetation types indicating thattheywere not headed to extinction however disturbed standsmay move to new species compositions in the future

Acknowledgments

The authors are thankful to the Ministry of Environmentand Forests for financial support and the Vice Chancellorof University of Delhi and the Director of Kerala ForestResearch Institute for facilities provided The first authorwould like to thank Professor C R Babu for facilities andencouragement The authors are very much obliged to allmembers of the Cholanaikkan tribe who helped duringthe field survey The Kerala Forest Department provided alllogistical support for the floristic and ecological survey of theforest area (trees haminus1) in three different growth phases of sixvegetation

References

[1] M A Huston Biological Diversity The Coexistence of Species inChanging Landscapes Cambridge University Press CambridgeUK 1994

[2] T C Whitmore An Introduction to Tropical Rain ForestsOxfordUniversity Press NewYork NYUSA 2nd edition 1998

[3] M L Khan S Menon and K S Bawa ldquoEffectiveness of theprotected area network in biodiversity conservation a case-study of Meghalaya staterdquo Biodiversity and Conservation vol 6no 6 pp 853ndash868 1997

[4] C M Pringle ldquoNutrient spatial heterogeneity effects on com-munity structure physiognomy and diversity of stream algaerdquoEcology vol 71 no 3 pp 905ndash920 1990

[5] M Parviainen M Marmion M Luoto W Thuiller and RK Heikkinen ldquoUsing summed individual species models andstate-of-the-art modelling techniques to identify threatenedplant species hotspotsrdquo Biological Conservation vol 142 no 11pp 2501ndash2509 2009

[6] J S Singh S P Singh A K Saxena and Y S Ravat ldquoThe forestvegetation of Silent Valleyrdquo in Tropical Rain Forests The LeedsSymposium pp 25ndash52 1984

[7] A O Varghese ldquoAssessment of biodiversity of PepparaWildlifeSanctuary Trivandrum District Keralardquo Journal of Economicand Taxonomic Botany vol 23 pp 117ndash127 1998

[8] M A Suraj Phytosociological and vagetation mapping at chim-mony wildlife Sanctuary (Kerala) using remote sensing technique[PhD thesis] FRI University Dehradun India 1997

[9] N Parthasarathy Studies on the vacular flora structure andnutrient cycling in Kalakad Reserve Forest Western Ghats TamilNadu [PhD thesis] University of Madras Tamil Nadu India1986

[10] S N Rai and J Proctor ldquoEcological studies on four rainforests in Karnataka India environment forest structure andvegetationrdquo Journal of Vegetation Science vol 1 pp 609ndash6141986

[11] U M Chadrashekara A R R Menon K K N Nair NSasidharan and K Swarupanandan ldquoEvaluating plant diversityin different forest types of Kerala by laying out permanent sam-ple plotsrdquo KFRI Research Report 156 Kerala Forest ResearchInstitute Peechi India 1998

[12] C S Jha and J S Singh ldquoComposition and dynamics of drytropical Forest in relation to soil texturerdquo Journal of VegetationScience vol 1 no 5 pp 609ndash614 1990

[13] NVisalakshi ldquoVegetation analysis of two tropical dry evergreenforests in southern IndiardquoTropical Ecology vol 36 no 1 pp 117ndash127 1995

ISRN Ecology 13

[14] T Ganesh R Ganesan M Soubadra Devy P Davidar and K SBawa ldquoAssessment of plant biodiversity at amid-elevation ever-green forest of Kalakad-Mundanthurai Tiger Reserve WesternGhats Indiardquo Current Science vol 71 no 5 pp 379ndash392 1996

[15] S M Sundarapandian and P S Swamy ldquoForest ecosystemstructure and composition along an altitudinal gradient in theWestern Ghats South Indiardquo Journal of Tropical Forest Sciencevol 12 no 1 pp 104ndash123 2000

[16] K Swarupanandan N Sasidharan K C Chacko and SChanduBasha ldquoFloristic and ecological studies on the Sholasof Idukki Districtrdquo in Shola Forests of Kerala Environmentand Biodiverstiy K K N Nair S K Khanduri and K Bala-subramaniayan Eds pp 259ndash286 Kerala Forest DeparmentThiruvanathapuram Kerala Forest Research Institute PeechiIndia 2001

[17] R W Thorington S Tannenbaum A Tarak and R RudranldquoDistribution of trees in Baro Colorado Islands a hectaresamplerdquo in The Ecology of a Tropical Forest-Seasonal Rhythmsand Long-term Changes E G Leigh Jr A S Rand and D MWindsor Eds Smithsonian Institute Press Washington DCUSA 1982

[18] S P Hubbell and R B Foster ldquoDiversity of canopy speciesin a neotropical forest and implications for conservationrdquo inTropical Rain Forest Ecology and Management S L Sutton TCWhitmore andA C Chadwick Eds Blackwell Oxford UK1983

[19] D G Campbell D C Daly G T Prance and U N MacielldquoQuantitative ecological inventory of terra firme and varzeatropical forest on the Rio Xingu Brazilian Amazonrdquo Brittoniavol 38 no 4 pp 369ndash393 1986

[20] S Itow ldquoSpecies diversity of equatorial insular forests on Ponapeand Kosrae Micronesiardquo Ecological Research vol 1 no 2 pp223ndash227 1986

[21] C C Ho D M Newbery and M E D Poore ldquoForestcomposition and inferred dynamics in Jengka Forest ReserveMalaysiardquo Journal of Tropical Ecology vol 3 no 1 pp 25ndash561987

[22] J Proctor Y F Lee A M Langley W R C Munro and TNelson ldquoEcological studies onGunung Silam a small ultrabasicmountain Sabah Malaysiardquo Journal of Ecology vol 74 pp 455ndash463 1988

[23] F R Swan Jr ldquoTree distribution patterns in the Bukittimahnature reserve Singaporerdquo Gardens Bulletin vol 41 pp 59ndash811988

[24] A Heaney and J Proctor ldquoPreliminary studies on foreststructure and floristics on Volcan Barva Costa Ricardquo Journalof Tropical Ecology vol 6 no 3 pp 307ndash320 1990

[25] T Jaffre and J M Veillon ldquoEtude floristique et structuralede deux forets denses humides sur roches ultrabasiques enNouvelle- Caledonierdquo Bulletin du Museum National drsquoHistoireNaturelle vol 12 pp 243ndash273 1990

[26] MMosango ldquoContribution ldquoA lrsquoetude botanic biogeo 1rdquo ecosys-tem Foret en region equatorial (Ile KongoloZaire)rdquo BelgiumJournal of Botany vol 124 pp 167ndash194 1991

[27] M Cao and J Zhang ldquoTree species diversity of tropical forestvegetation in Xishuangbanna SW Chinardquo Biodiversity andConservation vol 6 no 7 pp 995ndash1006 1997

[28] C S Jha L Goparaju A Tripathi B Gharai A S Raghubanshiand J S Singh ldquoForest fragmentation and its impact onspecies diversity an analysis using remote sensing and GISrdquoBiodiversity and Conservation vol 14 no 7 pp 1681ndash1698 2005

[29] P S Roy C B S Dutt and P K Joshi ldquoTropical forest resourceassessment and monitoringrdquo Tropical Ecology vol 43 no 1 pp21ndash37 2002

[30] R Sagar A S Raghubanshi and J S Singh ldquoAsymptoticmodelsof species-area curve for measuring diversity of dry tropicalforest tree speciesrdquo Current Science vol 84 no 12 pp 1555ndash1560 2003

[31] R Sukumar H S Dattaraja H S Suresh et al ldquoLong-termmonitoring of vegetation in a tropical deciduous forest inMudumalai southern Indiardquo Current Science vol 62 pp 608ndash616 1992

[32] UMChandrashekara and P S Ramakrishnan ldquoVegetation andgap dynamics of a tropical wet evergreen forest in the WesternGhats of Kerala Indiardquo Journal of Tropical Ecology vol 10 no3 pp 337ndash354 1994

[33] T Ganesh R Ganesan M Soubadra Devy P Davidar and K SBawa ldquoAssessment of plant biodiversity at amid-elevation ever-green forest of Kalakad-Mundanthurai Tiger Reserve WesternGhats Indiardquo Current Science vol 71 no 5 pp 379ndash392 1996

[34] J P Pascal and R Pelissier ldquoStructure and floristic compositionof a tropical evergreen forest in south-west Indiardquo Journal ofTropical Ecology vol 12 no 2 pp 191ndash210 1996

[35] N Ayyappan and N Parthasarathy ldquoBiodiversity inventory oftrees in a large-scale permanent plot of tropical evergreen forestat Varagalaiar Anamalais Western Ghats Indiardquo Biodiversityand Conservation vol 8 no 11 pp 1533ndash1554 1999

[36] A Kumar B G Marcot and A Saxena ldquoTree species diversityand distribution patterns in tropical forests of Garo HillsrdquoCurrent Science vol 91 no 10 pp 1370ndash1381 2006

[37] N Parthasarathy ldquoTree diversity and distribution in undis-turbed and human-impacted sites of tropical wet evergreenforest in southern Western Ghats Indiardquo Biodiversity andConservation vol 8 no 10 pp 1365ndash1381 1999

[38] M L Khan J P N Rai and R S Tripathi ldquoPopulation structureof some tree species in disturbed and protected subtropicalforests of north-east Indiardquo Acta Oecologica vol 8 no 3 pp247ndash255 1987

[39] R S Tripathi and M L Khan ldquoRegeneration pattern andpopulation structure of trees in subtropical forest of North EastIndiardquo in Tropical Ecosystem-Ecology and Management K PSingh and J S Singh Eds pp 431ndash441 Wiley Eastern LimitedNew Delhi India 1992

[40] A E Scholl and A H Taylor ldquoRegeneration patterns in old-growth red fir-western white pine forests in the northern SierraNevada Lake Tahoe USArdquo Forest Ecology and Managementvol 235 no 1ndash3 pp 143ndash154 2006

[41] D A Clark ldquoRegeneration of canopy trees in tropical wetforestsrdquo Trends in Ecology and Evolution vol 1 no 6 pp 150ndash154 1986

[42] P C J Barker and J B Kirkpatrick ldquoPhyllocladus aspleniifoliusvariability in the population structure the regeneration nicheand dispersion patterns in Tasmanian forestsrdquo Australian Jour-nal of Botany vol 42 no 2 pp 163ndash190 1994

[43] C K Augspurger ldquoSeedling survival of tropical tree speciesinteractions of dispersal distance light-gaps and pathogensrdquoEcology vol 65 no 6 pp 1705ndash1712 1984

[44] O L Phillips ldquoLong-term environmental change in tropicalforests increasing tree turnoverrdquo Environmental Conservationvol 23 no 3 pp 235ndash248 1996

[45] Ministry of Environment and Forests ldquoPlant discoveries 2011newgenera species andnew recordsrdquo Botanical Survey of IndiaMinistry of Environment and Forests New Delhi India 2012

14 ISRN Ecology

[46] ldquoWeblink 2007rdquo httpwwwbiodiversityhotspotsorgxphot-spotshotspots by region

[47] D Mueller-Dombois and H Ellenberg Aims and Methods ofPlant Ecology John Wiley amp Sons New York NY USA 1974

[48] K K N Nair and R Jayakumar ldquoPhytogeography endemismand affinities of the flora of NewAmarambalamReserve Forestsin theWesternGhats of Indiardquo Indian Journal of Forestry vol 31pp 85ndash94 2008

[49] A E Magurran Ecological Diversity and Its MeasurementCroom Helm Ltd London UK 1988

[50] C Raunkiaer The Life Forms of Plants and Statistical PlantGeography Clarendon Press Oxford UK 1934

[51] B Rice andMWestoby ldquoPlant species richness at the 01 hectarescale in Australian vegetation compared to other continentsrdquoVegetatio vol 52 no 3 pp 129ndash140 1983

[52] SM Scheiner ldquoSix types of species-area curvesrdquoGlobal Ecologyand Biogeography vol 12 no 6 pp 441ndash447 2003

[53] H G Jones Plants and Microclimate Cambridge UniversityPress Cambridge UK 1983

[54] N C Nair The Southern Western Ghats A Biodiversity Con-servation Plan Indian National Trust for Arts and CulturalHeritage New Delhi India 1991

[55] AHGentry ldquoChanges in plant community diversity and floris-tic composition on environmental and geographical gradientrdquoAnnals of the Missouri Botanical Garden vol 75 no 1 pp 1ndash341988

[56] T CWhitmore Tropical Rain Forests of the Far East ClarendonPress Oxford UK 1984

[57] N V L Brokaw ldquoGap-phase regeneration of three pioneer treespecies in a tropical forestrdquo Journal of Ecology vol 75 no 1 pp9ndash19 1987

[58] S Itow and D Mueller-Dombois ldquoPopulation structure stand-level dieback and recovery of Scalesia pedunculata forest in theGalapagos Islandsrdquo Ecological Research vol 3 no 3 pp 333ndash339 1988

[59] T CWhitmore ldquoA review of some aspects of tropical rainforestseedling ecology with suggestions for further enquiryrdquo inEcology of Tropical Forest Tree Seedlings M D Swaine Ed pp3ndash39 UNESCOParthenon Paris France 1996

Submit your manuscripts athttpwwwhindawicom

Forestry ResearchInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Environmental and Public Health

Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

EcosystemsJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

MeteorologyAdvances in

EcologyInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Marine BiologyJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom

Applied ampEnvironmentalSoil Science

Volume 2014

Advances in

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Environmental Chemistry

Atmospheric SciencesInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Waste ManagementJournal of

Hindawi Publishing Corporation httpwwwhindawicom Volume 2014

International Journal of

Geophysics

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Geological ResearchJournal of

EarthquakesJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

BiodiversityInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

ScientificaHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

OceanographyInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Journal of Computational Environmental SciencesHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

ClimatologyJournal of

Page 9: Research Article Species Diversity and Tree Regeneration ...downloads.hindawi.com/archive/2013/890862.pdf · Species Diversity and Tree Regeneration Patterns in Tropical Forests of

ISRN Ecology 9

3721 19 10 6 3 2 1 1

020406080

100DECI

Tree

s (

)

Girth classes

10ndash5

0

101ndash

150

151ndash

200

201ndash

250

251ndash

300

301ndash

350

351ndash

400

51ndash1

00

gt400

(a)

020406080

10060

20 9 3 2 2 21 1

SEMI

Tree

s (

)

Girth classes

10ndash5

0

101ndash

150

151ndash

200

201ndash

250

251ndash

300

301ndash

350

351ndash

400

51ndash1

00

gt400

(b)

020406080

10065

19 9 3 2 2 21 1

EVER

Tree

s (

)

Girth classes

10ndash5

0

101ndash

150

151ndash

200

201ndash

250

251ndash

300

301ndash

350

351ndash

400

51ndash1

00

gt400

(c)

020406080

100 96

4 0 0 0 0 0 0 0

WOOD

Tree

s (

)

Girth classes

10ndash5

0

101ndash

150

151ndash

200

201ndash

250

251ndash

300

301ndash

350

351ndash

400

51ndash1

00

gt400

(d)

020406080

10058

20 12 4 2 1 1 1 1

SUBM

Girth classes

10ndash5

0

101ndash

150

151ndash

200

201ndash

250

251ndash

300

301ndash

350

351ndash

400

Tree

s (

)

51ndash1

00

gt400

(e)

020406080

10070

243 2 1 0 0 0 0

MONT

Tree

s (

)

Girth classes

10ndash5

0

101ndash

150

151ndash

200

201ndash

250

251ndash

300

301ndash

350

351ndash

400

51ndash1

00

gt400

(f)

Figure 6 Girth frequency distributions of trees in different vegetation types of the study area Girth-size was highest in SEMI and EVER Ahigh percentage of lower girth class trees in DECI results from reduced fuel wood extraction by people of nearby areas The reverse J-shapedgbh distribution of trees indicates evolving or expanding population

and seedlings in DECI is due to overharvesting of saplingsfor firewood The lowest species diversity value in WOODindicates low species richness and dominance of one or twospecies in the tree community In the present study Shannonindex values for tree species are similar to values for othertropical forests of the world (Table 4) However detailedcomparisons with other studies are inadvisable because oflarge differences in sample size standard girth parametersand environmental conditions

Density and frequency distributions of trees contributeto the structure of tropical forests Tree density in DECI wasmuch lower than that of other forest types perhaps due to lowrainfall and anthropogenic disturbances Density was least inthe fire-affected WOOD Sapling densities were elevated inSEMI and EVER Late secondary successional species werewell represented in the sapling population of EVER whichmay be indicative of recent natural disturbances in this foresttype that promoted regeneration of late secondary speciesMONT had high sapling density due to the stunted nature oftrees caused by very low temperature and high wind velocityprevalent there [54]

Densities of trees in the study area were similar toestimates from tropical forests within India and other tropicalregions (Table 4) In tropical forests outside India there ismuch variation in the densities of trees gt30 cm gbh (98ndash1930 trees haminus1) especially in Amazonian forests In theNeotropics maximum species richness of tree individualsgt10 cm gbh reaches 300 haminus1 [55] In South-East Asia thehighest richness is 225 haminus1 [56]

In the present studymost of the species were in frequencyclass 0ndash20 and fewest were in frequency class 80ndash100The frequency distribution of tree species suggested thatmostof them had low frequency as would be expected in typicalspecies-abundance distribution A plant species should beconsidered homogeneously distributed when the numbersof individuals are the same in all parts of a community[50] Hence tree species in all the vegetation types of thestudy area were heterogeneously distributed Girth classfrequency distributions of most species in vegetation typeswe studied fit ldquoreverse Jrdquo-shaped patterns with most trees insmaller girth classes and few old trees Vegetation types otherthan WOOD fit negative exponential patterns indicative of

10 ISRN Ecology

Table4Ve

getatio

nparameterso

fforestcom

mun

ities

inthetropics

ofIndiaa

ndotherc

ountrie

s

Foresttypes

Locatio

nPlot

size(ha)

Tree

girth

studied

(cm)

Tree

density

(noha)

Tree

basal

area

(m2 ha)

Shanno

nindex

References

Presentstudy

DEC

IWestern

Ghats(N

BR)

4ha

ge30

cm132

234

279

Present

study

SEMI

ldquo4ha

ge30

cm368

457

367

ldquo

EVER

ldquo4ha

ge30

cm485

480

334

ldquo

WOOD

ldquo3ha

ge30

cm39

069

221

ldquo

SUBM

ldquo4ha

ge30

cm390

365

326

ldquo

MONT

ldquo4ha

ge30

cm855

309

321

ldquo

India

Evergreenforests

Silent

valleyWestern

Ghat

mdashge315

620ndash

709

29ndash103

mdash[6]

Moistdecidu

ousforests

Pepp

araWGhats

mdashge30

590ndash

740

13ndash51

2ndash33

[7]

Moistdecidu

ousforests

Chim

mon

yWestern

Ghats

mdashge30

558

3719

ndash24

[8]

Semievergreen

forests

Pepp

araWestern

Ghats

mdashge30

670ndash

940

45ndash6

229

[7]

Semievergreen

forests

Chim

mon

yWestern

Ghats

mdashge30

728

4727ndash32

[8]

Scrubjung

leto

wetevergreenforests

Kalakk

adRF

Western

Ghats

02

gt20

320ndash

1260

18ndash107

mdash[9]

Evergreenforests

Karnataka

044

mdash44

6ndash1386

33ndash4

8mdash

[10]

Evergreenforests

Pepp

ara

mdashge30

860ndash

1370

7633

[7]

Evergreenforests

NelliampathiWestern

Ghats

mdashge30

mdash498

3ndash37

[11]

Dry

tropicalforests

Vind

hyar

egion

mdashgt30

294ndash

559

7ndash23

mdash[12]

Dry

evergreenforests

Puthup

etSacred

GroveC

orom

andel

coast

02

gt20

280

11mdash

[13]

Trop

icalwe

tevergreen

forests

Kalakk

ad-M

undanthu

raiT

iger

Reserve

Western

Ghats

050

gt30

315ndash418

54ndash8

4mdash

[14]

Trop

icalwe

tevergreen

forests

KodayarWestern

Ghats

050

gt30

352ndash117

328ndash81

mdash[15]

Subtropicalh

illforests

Pepp

araWestern

Ghats

mdashge30

1580ndash1930

27ndash34

27

[7]

Mon

tane

temperateforests

Mannavanshola

mdashge30

566

52399

[16]

ISRN Ecology 11

Table4Con

tinued

Foresttypes

Locatio

nPlot

size(ha)

Tree

girth

studied

(cm)

Tree

density

(noha)

Tree

basal

area

(m2 ha)

Shanno

nindex

References

Other

coun

tries

Trop

icalrain

forests

(you

ngforests

)Ba

rrow

ColoradoIsland

Panam

a5

gt18

84ndash171

26ndash

52

mdash[17]

Trop

icalrain

forests

(old

forests

)Ba

rrow

ColoradoIsland

Panam

a50

gt18

143ndash177

43ndash5

mdash[18]

Trop

icalrain

forests

Amazon

ia3

314

1420

28ndash6

8mdash

[19]

Equatoria

linsular

forests

Easte

rnCa

rolline

Island

Panam

a50

gt314

98ndash114

17mdash

[20]

Trop

icalrain

forests

Jung

kaRe

serveMalaysia

1191

104

23mdash

[21]

Trop

icalrain

forests

Gun

ungSilamM

alaysia

004

314

513ndash1596

23ndash4

6mdash

[22]

Trop

icalmoistforests

Sing

apore

04

gt63

604

mdashmdash

[23]

Trop

icalrain

forests

Valcan

BarvaCostaRica

6gt314

391ndash617

mdashmdash

[24]

Slop

eforests

New

Caledo

nia

28

gt314

1533

49mdash

[25]

Allu

vium

forests

New

Caledo

nia

26

gt314

1183

47mdash

[25]

Equatoria

lforests

KongoIsland

mdashmdash

440ndash

553

10ndash4

5mdash

[26]

Trop

icalrain

forests

Amazon

ia3

gt314

1720

78mdash

[19]

Trop

icalseason

alrain

forests

Xishuang

bann

aCh

ina

2500

m2

15154

mdash34

[27]

Trop

icalmon

tane

rain

forests

Xishuang

bann

aCh

ina

1600

m2

15123

mdash32

[27]

Evergreenbroadleaved

forests

Xishuang

bann

aCh

ina

1200

m2

15165

mdash25

[27]

Mon

soon

forests

Xishuang

bann

aCh

ina

400m

210

150

mdash16

[27]

ldquoStudy

cond

uctedin

6different

vegetatio

ntypeso

fWestern

Ghats(N

BR)

12 ISRN Ecology

relatively undisturbed or less disturbed conditions in thestands The high annual precipitation rate and optimumtemperature of EVER may have contributed to high treegrowth rate and higher tree basal area

42 Regeneration All other vegetation types had betterregeneration than DECI In WOOD the transition rate ofstems from small girth classes to larger girth classes was lowPoor tree regeneration in DECI and WOOD can probablybe attributed to fuel wood collection frequent fires andgrazing by cattle In all forest types 29ndash47 of tree specieswere present in all three growth phases other species werepresent in either one or two growth phases Dominant speciesoccurred in all girth classes of vegetation types other thanWOOD in whichmost trees were in the smaller girth classesThere were more large trees in vegetation types like SEMIand EVER and in these sapling and seedling densities wereadequate for restocking the complement of canopy trees

Change in species composition across mature and regen-erating tree phases was more frequent in disturbed foresttypes like DECI and WOOD In some cases the dominantspecies in adult and seedling stages were quite differentin these two disturbed forest types Our results are notcongruent with observationsmade in northeastern India [39]where tree seedling survival rate increases with increasingforest disturbance We found species without regeneratingphases these are unlikely to persist Others that occurred onlyin seedling and sapling stages were new entrants to the forestspecies complement These are examples of discontinuouspopulation structures Such structures occur in a number ofother tropical countries [57ndash59] The dominant species in aforest stand is generally present in all size classes [38] Thesize class structures of trees indicate the probability of speciespersistence into the future this information is very valuablein the design of management strategies aiming to improvestand structure and species diversity Changes in speciescomposition and recruitment of new species in differentvegetation types are indicative of future species compositionin changing environments

5 Conclusions

The species diversity of trees varied across vegetation types inthe Western Ghats landscape Rarefaction curves show thatspecies diversity is highest in SEMI and EVER and lowest inWOOD while species abundance is highest in MONT Vege-tation types of study area are in heterogeneous in distributionThere were large differences in species composition of adulttrees and regenerating individuals in the disturbed vegetationtypes as compared to undisturbed stands The present studyreveals that the anthropogenic disturbance causes disruptionof forest structure and change in species composition whichultimately leads to reduction of tree species richness andabundance which are the major attributes of forests Newrecruits were found in all vegetation types indicating thattheywere not headed to extinction however disturbed standsmay move to new species compositions in the future

Acknowledgments

The authors are thankful to the Ministry of Environmentand Forests for financial support and the Vice Chancellorof University of Delhi and the Director of Kerala ForestResearch Institute for facilities provided The first authorwould like to thank Professor C R Babu for facilities andencouragement The authors are very much obliged to allmembers of the Cholanaikkan tribe who helped duringthe field survey The Kerala Forest Department provided alllogistical support for the floristic and ecological survey of theforest area (trees haminus1) in three different growth phases of sixvegetation

References

[1] M A Huston Biological Diversity The Coexistence of Species inChanging Landscapes Cambridge University Press CambridgeUK 1994

[2] T C Whitmore An Introduction to Tropical Rain ForestsOxfordUniversity Press NewYork NYUSA 2nd edition 1998

[3] M L Khan S Menon and K S Bawa ldquoEffectiveness of theprotected area network in biodiversity conservation a case-study of Meghalaya staterdquo Biodiversity and Conservation vol 6no 6 pp 853ndash868 1997

[4] C M Pringle ldquoNutrient spatial heterogeneity effects on com-munity structure physiognomy and diversity of stream algaerdquoEcology vol 71 no 3 pp 905ndash920 1990

[5] M Parviainen M Marmion M Luoto W Thuiller and RK Heikkinen ldquoUsing summed individual species models andstate-of-the-art modelling techniques to identify threatenedplant species hotspotsrdquo Biological Conservation vol 142 no 11pp 2501ndash2509 2009

[6] J S Singh S P Singh A K Saxena and Y S Ravat ldquoThe forestvegetation of Silent Valleyrdquo in Tropical Rain Forests The LeedsSymposium pp 25ndash52 1984

[7] A O Varghese ldquoAssessment of biodiversity of PepparaWildlifeSanctuary Trivandrum District Keralardquo Journal of Economicand Taxonomic Botany vol 23 pp 117ndash127 1998

[8] M A Suraj Phytosociological and vagetation mapping at chim-mony wildlife Sanctuary (Kerala) using remote sensing technique[PhD thesis] FRI University Dehradun India 1997

[9] N Parthasarathy Studies on the vacular flora structure andnutrient cycling in Kalakad Reserve Forest Western Ghats TamilNadu [PhD thesis] University of Madras Tamil Nadu India1986

[10] S N Rai and J Proctor ldquoEcological studies on four rainforests in Karnataka India environment forest structure andvegetationrdquo Journal of Vegetation Science vol 1 pp 609ndash6141986

[11] U M Chadrashekara A R R Menon K K N Nair NSasidharan and K Swarupanandan ldquoEvaluating plant diversityin different forest types of Kerala by laying out permanent sam-ple plotsrdquo KFRI Research Report 156 Kerala Forest ResearchInstitute Peechi India 1998

[12] C S Jha and J S Singh ldquoComposition and dynamics of drytropical Forest in relation to soil texturerdquo Journal of VegetationScience vol 1 no 5 pp 609ndash614 1990

[13] NVisalakshi ldquoVegetation analysis of two tropical dry evergreenforests in southern IndiardquoTropical Ecology vol 36 no 1 pp 117ndash127 1995

ISRN Ecology 13

[14] T Ganesh R Ganesan M Soubadra Devy P Davidar and K SBawa ldquoAssessment of plant biodiversity at amid-elevation ever-green forest of Kalakad-Mundanthurai Tiger Reserve WesternGhats Indiardquo Current Science vol 71 no 5 pp 379ndash392 1996

[15] S M Sundarapandian and P S Swamy ldquoForest ecosystemstructure and composition along an altitudinal gradient in theWestern Ghats South Indiardquo Journal of Tropical Forest Sciencevol 12 no 1 pp 104ndash123 2000

[16] K Swarupanandan N Sasidharan K C Chacko and SChanduBasha ldquoFloristic and ecological studies on the Sholasof Idukki Districtrdquo in Shola Forests of Kerala Environmentand Biodiverstiy K K N Nair S K Khanduri and K Bala-subramaniayan Eds pp 259ndash286 Kerala Forest DeparmentThiruvanathapuram Kerala Forest Research Institute PeechiIndia 2001

[17] R W Thorington S Tannenbaum A Tarak and R RudranldquoDistribution of trees in Baro Colorado Islands a hectaresamplerdquo in The Ecology of a Tropical Forest-Seasonal Rhythmsand Long-term Changes E G Leigh Jr A S Rand and D MWindsor Eds Smithsonian Institute Press Washington DCUSA 1982

[18] S P Hubbell and R B Foster ldquoDiversity of canopy speciesin a neotropical forest and implications for conservationrdquo inTropical Rain Forest Ecology and Management S L Sutton TCWhitmore andA C Chadwick Eds Blackwell Oxford UK1983

[19] D G Campbell D C Daly G T Prance and U N MacielldquoQuantitative ecological inventory of terra firme and varzeatropical forest on the Rio Xingu Brazilian Amazonrdquo Brittoniavol 38 no 4 pp 369ndash393 1986

[20] S Itow ldquoSpecies diversity of equatorial insular forests on Ponapeand Kosrae Micronesiardquo Ecological Research vol 1 no 2 pp223ndash227 1986

[21] C C Ho D M Newbery and M E D Poore ldquoForestcomposition and inferred dynamics in Jengka Forest ReserveMalaysiardquo Journal of Tropical Ecology vol 3 no 1 pp 25ndash561987

[22] J Proctor Y F Lee A M Langley W R C Munro and TNelson ldquoEcological studies onGunung Silam a small ultrabasicmountain Sabah Malaysiardquo Journal of Ecology vol 74 pp 455ndash463 1988

[23] F R Swan Jr ldquoTree distribution patterns in the Bukittimahnature reserve Singaporerdquo Gardens Bulletin vol 41 pp 59ndash811988

[24] A Heaney and J Proctor ldquoPreliminary studies on foreststructure and floristics on Volcan Barva Costa Ricardquo Journalof Tropical Ecology vol 6 no 3 pp 307ndash320 1990

[25] T Jaffre and J M Veillon ldquoEtude floristique et structuralede deux forets denses humides sur roches ultrabasiques enNouvelle- Caledonierdquo Bulletin du Museum National drsquoHistoireNaturelle vol 12 pp 243ndash273 1990

[26] MMosango ldquoContribution ldquoA lrsquoetude botanic biogeo 1rdquo ecosys-tem Foret en region equatorial (Ile KongoloZaire)rdquo BelgiumJournal of Botany vol 124 pp 167ndash194 1991

[27] M Cao and J Zhang ldquoTree species diversity of tropical forestvegetation in Xishuangbanna SW Chinardquo Biodiversity andConservation vol 6 no 7 pp 995ndash1006 1997

[28] C S Jha L Goparaju A Tripathi B Gharai A S Raghubanshiand J S Singh ldquoForest fragmentation and its impact onspecies diversity an analysis using remote sensing and GISrdquoBiodiversity and Conservation vol 14 no 7 pp 1681ndash1698 2005

[29] P S Roy C B S Dutt and P K Joshi ldquoTropical forest resourceassessment and monitoringrdquo Tropical Ecology vol 43 no 1 pp21ndash37 2002

[30] R Sagar A S Raghubanshi and J S Singh ldquoAsymptoticmodelsof species-area curve for measuring diversity of dry tropicalforest tree speciesrdquo Current Science vol 84 no 12 pp 1555ndash1560 2003

[31] R Sukumar H S Dattaraja H S Suresh et al ldquoLong-termmonitoring of vegetation in a tropical deciduous forest inMudumalai southern Indiardquo Current Science vol 62 pp 608ndash616 1992

[32] UMChandrashekara and P S Ramakrishnan ldquoVegetation andgap dynamics of a tropical wet evergreen forest in the WesternGhats of Kerala Indiardquo Journal of Tropical Ecology vol 10 no3 pp 337ndash354 1994

[33] T Ganesh R Ganesan M Soubadra Devy P Davidar and K SBawa ldquoAssessment of plant biodiversity at amid-elevation ever-green forest of Kalakad-Mundanthurai Tiger Reserve WesternGhats Indiardquo Current Science vol 71 no 5 pp 379ndash392 1996

[34] J P Pascal and R Pelissier ldquoStructure and floristic compositionof a tropical evergreen forest in south-west Indiardquo Journal ofTropical Ecology vol 12 no 2 pp 191ndash210 1996

[35] N Ayyappan and N Parthasarathy ldquoBiodiversity inventory oftrees in a large-scale permanent plot of tropical evergreen forestat Varagalaiar Anamalais Western Ghats Indiardquo Biodiversityand Conservation vol 8 no 11 pp 1533ndash1554 1999

[36] A Kumar B G Marcot and A Saxena ldquoTree species diversityand distribution patterns in tropical forests of Garo HillsrdquoCurrent Science vol 91 no 10 pp 1370ndash1381 2006

[37] N Parthasarathy ldquoTree diversity and distribution in undis-turbed and human-impacted sites of tropical wet evergreenforest in southern Western Ghats Indiardquo Biodiversity andConservation vol 8 no 10 pp 1365ndash1381 1999

[38] M L Khan J P N Rai and R S Tripathi ldquoPopulation structureof some tree species in disturbed and protected subtropicalforests of north-east Indiardquo Acta Oecologica vol 8 no 3 pp247ndash255 1987

[39] R S Tripathi and M L Khan ldquoRegeneration pattern andpopulation structure of trees in subtropical forest of North EastIndiardquo in Tropical Ecosystem-Ecology and Management K PSingh and J S Singh Eds pp 431ndash441 Wiley Eastern LimitedNew Delhi India 1992

[40] A E Scholl and A H Taylor ldquoRegeneration patterns in old-growth red fir-western white pine forests in the northern SierraNevada Lake Tahoe USArdquo Forest Ecology and Managementvol 235 no 1ndash3 pp 143ndash154 2006

[41] D A Clark ldquoRegeneration of canopy trees in tropical wetforestsrdquo Trends in Ecology and Evolution vol 1 no 6 pp 150ndash154 1986

[42] P C J Barker and J B Kirkpatrick ldquoPhyllocladus aspleniifoliusvariability in the population structure the regeneration nicheand dispersion patterns in Tasmanian forestsrdquo Australian Jour-nal of Botany vol 42 no 2 pp 163ndash190 1994

[43] C K Augspurger ldquoSeedling survival of tropical tree speciesinteractions of dispersal distance light-gaps and pathogensrdquoEcology vol 65 no 6 pp 1705ndash1712 1984

[44] O L Phillips ldquoLong-term environmental change in tropicalforests increasing tree turnoverrdquo Environmental Conservationvol 23 no 3 pp 235ndash248 1996

[45] Ministry of Environment and Forests ldquoPlant discoveries 2011newgenera species andnew recordsrdquo Botanical Survey of IndiaMinistry of Environment and Forests New Delhi India 2012

14 ISRN Ecology

[46] ldquoWeblink 2007rdquo httpwwwbiodiversityhotspotsorgxphot-spotshotspots by region

[47] D Mueller-Dombois and H Ellenberg Aims and Methods ofPlant Ecology John Wiley amp Sons New York NY USA 1974

[48] K K N Nair and R Jayakumar ldquoPhytogeography endemismand affinities of the flora of NewAmarambalamReserve Forestsin theWesternGhats of Indiardquo Indian Journal of Forestry vol 31pp 85ndash94 2008

[49] A E Magurran Ecological Diversity and Its MeasurementCroom Helm Ltd London UK 1988

[50] C Raunkiaer The Life Forms of Plants and Statistical PlantGeography Clarendon Press Oxford UK 1934

[51] B Rice andMWestoby ldquoPlant species richness at the 01 hectarescale in Australian vegetation compared to other continentsrdquoVegetatio vol 52 no 3 pp 129ndash140 1983

[52] SM Scheiner ldquoSix types of species-area curvesrdquoGlobal Ecologyand Biogeography vol 12 no 6 pp 441ndash447 2003

[53] H G Jones Plants and Microclimate Cambridge UniversityPress Cambridge UK 1983

[54] N C Nair The Southern Western Ghats A Biodiversity Con-servation Plan Indian National Trust for Arts and CulturalHeritage New Delhi India 1991

[55] AHGentry ldquoChanges in plant community diversity and floris-tic composition on environmental and geographical gradientrdquoAnnals of the Missouri Botanical Garden vol 75 no 1 pp 1ndash341988

[56] T CWhitmore Tropical Rain Forests of the Far East ClarendonPress Oxford UK 1984

[57] N V L Brokaw ldquoGap-phase regeneration of three pioneer treespecies in a tropical forestrdquo Journal of Ecology vol 75 no 1 pp9ndash19 1987

[58] S Itow and D Mueller-Dombois ldquoPopulation structure stand-level dieback and recovery of Scalesia pedunculata forest in theGalapagos Islandsrdquo Ecological Research vol 3 no 3 pp 333ndash339 1988

[59] T CWhitmore ldquoA review of some aspects of tropical rainforestseedling ecology with suggestions for further enquiryrdquo inEcology of Tropical Forest Tree Seedlings M D Swaine Ed pp3ndash39 UNESCOParthenon Paris France 1996

Submit your manuscripts athttpwwwhindawicom

Forestry ResearchInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Environmental and Public Health

Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

EcosystemsJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

MeteorologyAdvances in

EcologyInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Marine BiologyJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom

Applied ampEnvironmentalSoil Science

Volume 2014

Advances in

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Environmental Chemistry

Atmospheric SciencesInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Waste ManagementJournal of

Hindawi Publishing Corporation httpwwwhindawicom Volume 2014

International Journal of

Geophysics

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Geological ResearchJournal of

EarthquakesJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

BiodiversityInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

ScientificaHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

OceanographyInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Journal of Computational Environmental SciencesHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

ClimatologyJournal of

Page 10: Research Article Species Diversity and Tree Regeneration ...downloads.hindawi.com/archive/2013/890862.pdf · Species Diversity and Tree Regeneration Patterns in Tropical Forests of

10 ISRN Ecology

Table4Ve

getatio

nparameterso

fforestcom

mun

ities

inthetropics

ofIndiaa

ndotherc

ountrie

s

Foresttypes

Locatio

nPlot

size(ha)

Tree

girth

studied

(cm)

Tree

density

(noha)

Tree

basal

area

(m2 ha)

Shanno

nindex

References

Presentstudy

DEC

IWestern

Ghats(N

BR)

4ha

ge30

cm132

234

279

Present

study

SEMI

ldquo4ha

ge30

cm368

457

367

ldquo

EVER

ldquo4ha

ge30

cm485

480

334

ldquo

WOOD

ldquo3ha

ge30

cm39

069

221

ldquo

SUBM

ldquo4ha

ge30

cm390

365

326

ldquo

MONT

ldquo4ha

ge30

cm855

309

321

ldquo

India

Evergreenforests

Silent

valleyWestern

Ghat

mdashge315

620ndash

709

29ndash103

mdash[6]

Moistdecidu

ousforests

Pepp

araWGhats

mdashge30

590ndash

740

13ndash51

2ndash33

[7]

Moistdecidu

ousforests

Chim

mon

yWestern

Ghats

mdashge30

558

3719

ndash24

[8]

Semievergreen

forests

Pepp

araWestern

Ghats

mdashge30

670ndash

940

45ndash6

229

[7]

Semievergreen

forests

Chim

mon

yWestern

Ghats

mdashge30

728

4727ndash32

[8]

Scrubjung

leto

wetevergreenforests

Kalakk

adRF

Western

Ghats

02

gt20

320ndash

1260

18ndash107

mdash[9]

Evergreenforests

Karnataka

044

mdash44

6ndash1386

33ndash4

8mdash

[10]

Evergreenforests

Pepp

ara

mdashge30

860ndash

1370

7633

[7]

Evergreenforests

NelliampathiWestern

Ghats

mdashge30

mdash498

3ndash37

[11]

Dry

tropicalforests

Vind

hyar

egion

mdashgt30

294ndash

559

7ndash23

mdash[12]

Dry

evergreenforests

Puthup

etSacred

GroveC

orom

andel

coast

02

gt20

280

11mdash

[13]

Trop

icalwe

tevergreen

forests

Kalakk

ad-M

undanthu

raiT

iger

Reserve

Western

Ghats

050

gt30

315ndash418

54ndash8

4mdash

[14]

Trop

icalwe

tevergreen

forests

KodayarWestern

Ghats

050

gt30

352ndash117

328ndash81

mdash[15]

Subtropicalh

illforests

Pepp

araWestern

Ghats

mdashge30

1580ndash1930

27ndash34

27

[7]

Mon

tane

temperateforests

Mannavanshola

mdashge30

566

52399

[16]

ISRN Ecology 11

Table4Con

tinued

Foresttypes

Locatio

nPlot

size(ha)

Tree

girth

studied

(cm)

Tree

density

(noha)

Tree

basal

area

(m2 ha)

Shanno

nindex

References

Other

coun

tries

Trop

icalrain

forests

(you

ngforests

)Ba

rrow

ColoradoIsland

Panam

a5

gt18

84ndash171

26ndash

52

mdash[17]

Trop

icalrain

forests

(old

forests

)Ba

rrow

ColoradoIsland

Panam

a50

gt18

143ndash177

43ndash5

mdash[18]

Trop

icalrain

forests

Amazon

ia3

314

1420

28ndash6

8mdash

[19]

Equatoria

linsular

forests

Easte

rnCa

rolline

Island

Panam

a50

gt314

98ndash114

17mdash

[20]

Trop

icalrain

forests

Jung

kaRe

serveMalaysia

1191

104

23mdash

[21]

Trop

icalrain

forests

Gun

ungSilamM

alaysia

004

314

513ndash1596

23ndash4

6mdash

[22]

Trop

icalmoistforests

Sing

apore

04

gt63

604

mdashmdash

[23]

Trop

icalrain

forests

Valcan

BarvaCostaRica

6gt314

391ndash617

mdashmdash

[24]

Slop

eforests

New

Caledo

nia

28

gt314

1533

49mdash

[25]

Allu

vium

forests

New

Caledo

nia

26

gt314

1183

47mdash

[25]

Equatoria

lforests

KongoIsland

mdashmdash

440ndash

553

10ndash4

5mdash

[26]

Trop

icalrain

forests

Amazon

ia3

gt314

1720

78mdash

[19]

Trop

icalseason

alrain

forests

Xishuang

bann

aCh

ina

2500

m2

15154

mdash34

[27]

Trop

icalmon

tane

rain

forests

Xishuang

bann

aCh

ina

1600

m2

15123

mdash32

[27]

Evergreenbroadleaved

forests

Xishuang

bann

aCh

ina

1200

m2

15165

mdash25

[27]

Mon

soon

forests

Xishuang

bann

aCh

ina

400m

210

150

mdash16

[27]

ldquoStudy

cond

uctedin

6different

vegetatio

ntypeso

fWestern

Ghats(N

BR)

12 ISRN Ecology

relatively undisturbed or less disturbed conditions in thestands The high annual precipitation rate and optimumtemperature of EVER may have contributed to high treegrowth rate and higher tree basal area

42 Regeneration All other vegetation types had betterregeneration than DECI In WOOD the transition rate ofstems from small girth classes to larger girth classes was lowPoor tree regeneration in DECI and WOOD can probablybe attributed to fuel wood collection frequent fires andgrazing by cattle In all forest types 29ndash47 of tree specieswere present in all three growth phases other species werepresent in either one or two growth phases Dominant speciesoccurred in all girth classes of vegetation types other thanWOOD in whichmost trees were in the smaller girth classesThere were more large trees in vegetation types like SEMIand EVER and in these sapling and seedling densities wereadequate for restocking the complement of canopy trees

Change in species composition across mature and regen-erating tree phases was more frequent in disturbed foresttypes like DECI and WOOD In some cases the dominantspecies in adult and seedling stages were quite differentin these two disturbed forest types Our results are notcongruent with observationsmade in northeastern India [39]where tree seedling survival rate increases with increasingforest disturbance We found species without regeneratingphases these are unlikely to persist Others that occurred onlyin seedling and sapling stages were new entrants to the forestspecies complement These are examples of discontinuouspopulation structures Such structures occur in a number ofother tropical countries [57ndash59] The dominant species in aforest stand is generally present in all size classes [38] Thesize class structures of trees indicate the probability of speciespersistence into the future this information is very valuablein the design of management strategies aiming to improvestand structure and species diversity Changes in speciescomposition and recruitment of new species in differentvegetation types are indicative of future species compositionin changing environments

5 Conclusions

The species diversity of trees varied across vegetation types inthe Western Ghats landscape Rarefaction curves show thatspecies diversity is highest in SEMI and EVER and lowest inWOOD while species abundance is highest in MONT Vege-tation types of study area are in heterogeneous in distributionThere were large differences in species composition of adulttrees and regenerating individuals in the disturbed vegetationtypes as compared to undisturbed stands The present studyreveals that the anthropogenic disturbance causes disruptionof forest structure and change in species composition whichultimately leads to reduction of tree species richness andabundance which are the major attributes of forests Newrecruits were found in all vegetation types indicating thattheywere not headed to extinction however disturbed standsmay move to new species compositions in the future

Acknowledgments

The authors are thankful to the Ministry of Environmentand Forests for financial support and the Vice Chancellorof University of Delhi and the Director of Kerala ForestResearch Institute for facilities provided The first authorwould like to thank Professor C R Babu for facilities andencouragement The authors are very much obliged to allmembers of the Cholanaikkan tribe who helped duringthe field survey The Kerala Forest Department provided alllogistical support for the floristic and ecological survey of theforest area (trees haminus1) in three different growth phases of sixvegetation

References

[1] M A Huston Biological Diversity The Coexistence of Species inChanging Landscapes Cambridge University Press CambridgeUK 1994

[2] T C Whitmore An Introduction to Tropical Rain ForestsOxfordUniversity Press NewYork NYUSA 2nd edition 1998

[3] M L Khan S Menon and K S Bawa ldquoEffectiveness of theprotected area network in biodiversity conservation a case-study of Meghalaya staterdquo Biodiversity and Conservation vol 6no 6 pp 853ndash868 1997

[4] C M Pringle ldquoNutrient spatial heterogeneity effects on com-munity structure physiognomy and diversity of stream algaerdquoEcology vol 71 no 3 pp 905ndash920 1990

[5] M Parviainen M Marmion M Luoto W Thuiller and RK Heikkinen ldquoUsing summed individual species models andstate-of-the-art modelling techniques to identify threatenedplant species hotspotsrdquo Biological Conservation vol 142 no 11pp 2501ndash2509 2009

[6] J S Singh S P Singh A K Saxena and Y S Ravat ldquoThe forestvegetation of Silent Valleyrdquo in Tropical Rain Forests The LeedsSymposium pp 25ndash52 1984

[7] A O Varghese ldquoAssessment of biodiversity of PepparaWildlifeSanctuary Trivandrum District Keralardquo Journal of Economicand Taxonomic Botany vol 23 pp 117ndash127 1998

[8] M A Suraj Phytosociological and vagetation mapping at chim-mony wildlife Sanctuary (Kerala) using remote sensing technique[PhD thesis] FRI University Dehradun India 1997

[9] N Parthasarathy Studies on the vacular flora structure andnutrient cycling in Kalakad Reserve Forest Western Ghats TamilNadu [PhD thesis] University of Madras Tamil Nadu India1986

[10] S N Rai and J Proctor ldquoEcological studies on four rainforests in Karnataka India environment forest structure andvegetationrdquo Journal of Vegetation Science vol 1 pp 609ndash6141986

[11] U M Chadrashekara A R R Menon K K N Nair NSasidharan and K Swarupanandan ldquoEvaluating plant diversityin different forest types of Kerala by laying out permanent sam-ple plotsrdquo KFRI Research Report 156 Kerala Forest ResearchInstitute Peechi India 1998

[12] C S Jha and J S Singh ldquoComposition and dynamics of drytropical Forest in relation to soil texturerdquo Journal of VegetationScience vol 1 no 5 pp 609ndash614 1990

[13] NVisalakshi ldquoVegetation analysis of two tropical dry evergreenforests in southern IndiardquoTropical Ecology vol 36 no 1 pp 117ndash127 1995

ISRN Ecology 13

[14] T Ganesh R Ganesan M Soubadra Devy P Davidar and K SBawa ldquoAssessment of plant biodiversity at amid-elevation ever-green forest of Kalakad-Mundanthurai Tiger Reserve WesternGhats Indiardquo Current Science vol 71 no 5 pp 379ndash392 1996

[15] S M Sundarapandian and P S Swamy ldquoForest ecosystemstructure and composition along an altitudinal gradient in theWestern Ghats South Indiardquo Journal of Tropical Forest Sciencevol 12 no 1 pp 104ndash123 2000

[16] K Swarupanandan N Sasidharan K C Chacko and SChanduBasha ldquoFloristic and ecological studies on the Sholasof Idukki Districtrdquo in Shola Forests of Kerala Environmentand Biodiverstiy K K N Nair S K Khanduri and K Bala-subramaniayan Eds pp 259ndash286 Kerala Forest DeparmentThiruvanathapuram Kerala Forest Research Institute PeechiIndia 2001

[17] R W Thorington S Tannenbaum A Tarak and R RudranldquoDistribution of trees in Baro Colorado Islands a hectaresamplerdquo in The Ecology of a Tropical Forest-Seasonal Rhythmsand Long-term Changes E G Leigh Jr A S Rand and D MWindsor Eds Smithsonian Institute Press Washington DCUSA 1982

[18] S P Hubbell and R B Foster ldquoDiversity of canopy speciesin a neotropical forest and implications for conservationrdquo inTropical Rain Forest Ecology and Management S L Sutton TCWhitmore andA C Chadwick Eds Blackwell Oxford UK1983

[19] D G Campbell D C Daly G T Prance and U N MacielldquoQuantitative ecological inventory of terra firme and varzeatropical forest on the Rio Xingu Brazilian Amazonrdquo Brittoniavol 38 no 4 pp 369ndash393 1986

[20] S Itow ldquoSpecies diversity of equatorial insular forests on Ponapeand Kosrae Micronesiardquo Ecological Research vol 1 no 2 pp223ndash227 1986

[21] C C Ho D M Newbery and M E D Poore ldquoForestcomposition and inferred dynamics in Jengka Forest ReserveMalaysiardquo Journal of Tropical Ecology vol 3 no 1 pp 25ndash561987

[22] J Proctor Y F Lee A M Langley W R C Munro and TNelson ldquoEcological studies onGunung Silam a small ultrabasicmountain Sabah Malaysiardquo Journal of Ecology vol 74 pp 455ndash463 1988

[23] F R Swan Jr ldquoTree distribution patterns in the Bukittimahnature reserve Singaporerdquo Gardens Bulletin vol 41 pp 59ndash811988

[24] A Heaney and J Proctor ldquoPreliminary studies on foreststructure and floristics on Volcan Barva Costa Ricardquo Journalof Tropical Ecology vol 6 no 3 pp 307ndash320 1990

[25] T Jaffre and J M Veillon ldquoEtude floristique et structuralede deux forets denses humides sur roches ultrabasiques enNouvelle- Caledonierdquo Bulletin du Museum National drsquoHistoireNaturelle vol 12 pp 243ndash273 1990

[26] MMosango ldquoContribution ldquoA lrsquoetude botanic biogeo 1rdquo ecosys-tem Foret en region equatorial (Ile KongoloZaire)rdquo BelgiumJournal of Botany vol 124 pp 167ndash194 1991

[27] M Cao and J Zhang ldquoTree species diversity of tropical forestvegetation in Xishuangbanna SW Chinardquo Biodiversity andConservation vol 6 no 7 pp 995ndash1006 1997

[28] C S Jha L Goparaju A Tripathi B Gharai A S Raghubanshiand J S Singh ldquoForest fragmentation and its impact onspecies diversity an analysis using remote sensing and GISrdquoBiodiversity and Conservation vol 14 no 7 pp 1681ndash1698 2005

[29] P S Roy C B S Dutt and P K Joshi ldquoTropical forest resourceassessment and monitoringrdquo Tropical Ecology vol 43 no 1 pp21ndash37 2002

[30] R Sagar A S Raghubanshi and J S Singh ldquoAsymptoticmodelsof species-area curve for measuring diversity of dry tropicalforest tree speciesrdquo Current Science vol 84 no 12 pp 1555ndash1560 2003

[31] R Sukumar H S Dattaraja H S Suresh et al ldquoLong-termmonitoring of vegetation in a tropical deciduous forest inMudumalai southern Indiardquo Current Science vol 62 pp 608ndash616 1992

[32] UMChandrashekara and P S Ramakrishnan ldquoVegetation andgap dynamics of a tropical wet evergreen forest in the WesternGhats of Kerala Indiardquo Journal of Tropical Ecology vol 10 no3 pp 337ndash354 1994

[33] T Ganesh R Ganesan M Soubadra Devy P Davidar and K SBawa ldquoAssessment of plant biodiversity at amid-elevation ever-green forest of Kalakad-Mundanthurai Tiger Reserve WesternGhats Indiardquo Current Science vol 71 no 5 pp 379ndash392 1996

[34] J P Pascal and R Pelissier ldquoStructure and floristic compositionof a tropical evergreen forest in south-west Indiardquo Journal ofTropical Ecology vol 12 no 2 pp 191ndash210 1996

[35] N Ayyappan and N Parthasarathy ldquoBiodiversity inventory oftrees in a large-scale permanent plot of tropical evergreen forestat Varagalaiar Anamalais Western Ghats Indiardquo Biodiversityand Conservation vol 8 no 11 pp 1533ndash1554 1999

[36] A Kumar B G Marcot and A Saxena ldquoTree species diversityand distribution patterns in tropical forests of Garo HillsrdquoCurrent Science vol 91 no 10 pp 1370ndash1381 2006

[37] N Parthasarathy ldquoTree diversity and distribution in undis-turbed and human-impacted sites of tropical wet evergreenforest in southern Western Ghats Indiardquo Biodiversity andConservation vol 8 no 10 pp 1365ndash1381 1999

[38] M L Khan J P N Rai and R S Tripathi ldquoPopulation structureof some tree species in disturbed and protected subtropicalforests of north-east Indiardquo Acta Oecologica vol 8 no 3 pp247ndash255 1987

[39] R S Tripathi and M L Khan ldquoRegeneration pattern andpopulation structure of trees in subtropical forest of North EastIndiardquo in Tropical Ecosystem-Ecology and Management K PSingh and J S Singh Eds pp 431ndash441 Wiley Eastern LimitedNew Delhi India 1992

[40] A E Scholl and A H Taylor ldquoRegeneration patterns in old-growth red fir-western white pine forests in the northern SierraNevada Lake Tahoe USArdquo Forest Ecology and Managementvol 235 no 1ndash3 pp 143ndash154 2006

[41] D A Clark ldquoRegeneration of canopy trees in tropical wetforestsrdquo Trends in Ecology and Evolution vol 1 no 6 pp 150ndash154 1986

[42] P C J Barker and J B Kirkpatrick ldquoPhyllocladus aspleniifoliusvariability in the population structure the regeneration nicheand dispersion patterns in Tasmanian forestsrdquo Australian Jour-nal of Botany vol 42 no 2 pp 163ndash190 1994

[43] C K Augspurger ldquoSeedling survival of tropical tree speciesinteractions of dispersal distance light-gaps and pathogensrdquoEcology vol 65 no 6 pp 1705ndash1712 1984

[44] O L Phillips ldquoLong-term environmental change in tropicalforests increasing tree turnoverrdquo Environmental Conservationvol 23 no 3 pp 235ndash248 1996

[45] Ministry of Environment and Forests ldquoPlant discoveries 2011newgenera species andnew recordsrdquo Botanical Survey of IndiaMinistry of Environment and Forests New Delhi India 2012

14 ISRN Ecology

[46] ldquoWeblink 2007rdquo httpwwwbiodiversityhotspotsorgxphot-spotshotspots by region

[47] D Mueller-Dombois and H Ellenberg Aims and Methods ofPlant Ecology John Wiley amp Sons New York NY USA 1974

[48] K K N Nair and R Jayakumar ldquoPhytogeography endemismand affinities of the flora of NewAmarambalamReserve Forestsin theWesternGhats of Indiardquo Indian Journal of Forestry vol 31pp 85ndash94 2008

[49] A E Magurran Ecological Diversity and Its MeasurementCroom Helm Ltd London UK 1988

[50] C Raunkiaer The Life Forms of Plants and Statistical PlantGeography Clarendon Press Oxford UK 1934

[51] B Rice andMWestoby ldquoPlant species richness at the 01 hectarescale in Australian vegetation compared to other continentsrdquoVegetatio vol 52 no 3 pp 129ndash140 1983

[52] SM Scheiner ldquoSix types of species-area curvesrdquoGlobal Ecologyand Biogeography vol 12 no 6 pp 441ndash447 2003

[53] H G Jones Plants and Microclimate Cambridge UniversityPress Cambridge UK 1983

[54] N C Nair The Southern Western Ghats A Biodiversity Con-servation Plan Indian National Trust for Arts and CulturalHeritage New Delhi India 1991

[55] AHGentry ldquoChanges in plant community diversity and floris-tic composition on environmental and geographical gradientrdquoAnnals of the Missouri Botanical Garden vol 75 no 1 pp 1ndash341988

[56] T CWhitmore Tropical Rain Forests of the Far East ClarendonPress Oxford UK 1984

[57] N V L Brokaw ldquoGap-phase regeneration of three pioneer treespecies in a tropical forestrdquo Journal of Ecology vol 75 no 1 pp9ndash19 1987

[58] S Itow and D Mueller-Dombois ldquoPopulation structure stand-level dieback and recovery of Scalesia pedunculata forest in theGalapagos Islandsrdquo Ecological Research vol 3 no 3 pp 333ndash339 1988

[59] T CWhitmore ldquoA review of some aspects of tropical rainforestseedling ecology with suggestions for further enquiryrdquo inEcology of Tropical Forest Tree Seedlings M D Swaine Ed pp3ndash39 UNESCOParthenon Paris France 1996

Submit your manuscripts athttpwwwhindawicom

Forestry ResearchInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Environmental and Public Health

Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

EcosystemsJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

MeteorologyAdvances in

EcologyInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Marine BiologyJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom

Applied ampEnvironmentalSoil Science

Volume 2014

Advances in

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Environmental Chemistry

Atmospheric SciencesInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Waste ManagementJournal of

Hindawi Publishing Corporation httpwwwhindawicom Volume 2014

International Journal of

Geophysics

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Geological ResearchJournal of

EarthquakesJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

BiodiversityInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

ScientificaHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

OceanographyInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Journal of Computational Environmental SciencesHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

ClimatologyJournal of

Page 11: Research Article Species Diversity and Tree Regeneration ...downloads.hindawi.com/archive/2013/890862.pdf · Species Diversity and Tree Regeneration Patterns in Tropical Forests of

ISRN Ecology 11

Table4Con

tinued

Foresttypes

Locatio

nPlot

size(ha)

Tree

girth

studied

(cm)

Tree

density

(noha)

Tree

basal

area

(m2 ha)

Shanno

nindex

References

Other

coun

tries

Trop

icalrain

forests

(you

ngforests

)Ba

rrow

ColoradoIsland

Panam

a5

gt18

84ndash171

26ndash

52

mdash[17]

Trop

icalrain

forests

(old

forests

)Ba

rrow

ColoradoIsland

Panam

a50

gt18

143ndash177

43ndash5

mdash[18]

Trop

icalrain

forests

Amazon

ia3

314

1420

28ndash6

8mdash

[19]

Equatoria

linsular

forests

Easte

rnCa

rolline

Island

Panam

a50

gt314

98ndash114

17mdash

[20]

Trop

icalrain

forests

Jung

kaRe

serveMalaysia

1191

104

23mdash

[21]

Trop

icalrain

forests

Gun

ungSilamM

alaysia

004

314

513ndash1596

23ndash4

6mdash

[22]

Trop

icalmoistforests

Sing

apore

04

gt63

604

mdashmdash

[23]

Trop

icalrain

forests

Valcan

BarvaCostaRica

6gt314

391ndash617

mdashmdash

[24]

Slop

eforests

New

Caledo

nia

28

gt314

1533

49mdash

[25]

Allu

vium

forests

New

Caledo

nia

26

gt314

1183

47mdash

[25]

Equatoria

lforests

KongoIsland

mdashmdash

440ndash

553

10ndash4

5mdash

[26]

Trop

icalrain

forests

Amazon

ia3

gt314

1720

78mdash

[19]

Trop

icalseason

alrain

forests

Xishuang

bann

aCh

ina

2500

m2

15154

mdash34

[27]

Trop

icalmon

tane

rain

forests

Xishuang

bann

aCh

ina

1600

m2

15123

mdash32

[27]

Evergreenbroadleaved

forests

Xishuang

bann

aCh

ina

1200

m2

15165

mdash25

[27]

Mon

soon

forests

Xishuang

bann

aCh

ina

400m

210

150

mdash16

[27]

ldquoStudy

cond

uctedin

6different

vegetatio

ntypeso

fWestern

Ghats(N

BR)

12 ISRN Ecology

relatively undisturbed or less disturbed conditions in thestands The high annual precipitation rate and optimumtemperature of EVER may have contributed to high treegrowth rate and higher tree basal area

42 Regeneration All other vegetation types had betterregeneration than DECI In WOOD the transition rate ofstems from small girth classes to larger girth classes was lowPoor tree regeneration in DECI and WOOD can probablybe attributed to fuel wood collection frequent fires andgrazing by cattle In all forest types 29ndash47 of tree specieswere present in all three growth phases other species werepresent in either one or two growth phases Dominant speciesoccurred in all girth classes of vegetation types other thanWOOD in whichmost trees were in the smaller girth classesThere were more large trees in vegetation types like SEMIand EVER and in these sapling and seedling densities wereadequate for restocking the complement of canopy trees

Change in species composition across mature and regen-erating tree phases was more frequent in disturbed foresttypes like DECI and WOOD In some cases the dominantspecies in adult and seedling stages were quite differentin these two disturbed forest types Our results are notcongruent with observationsmade in northeastern India [39]where tree seedling survival rate increases with increasingforest disturbance We found species without regeneratingphases these are unlikely to persist Others that occurred onlyin seedling and sapling stages were new entrants to the forestspecies complement These are examples of discontinuouspopulation structures Such structures occur in a number ofother tropical countries [57ndash59] The dominant species in aforest stand is generally present in all size classes [38] Thesize class structures of trees indicate the probability of speciespersistence into the future this information is very valuablein the design of management strategies aiming to improvestand structure and species diversity Changes in speciescomposition and recruitment of new species in differentvegetation types are indicative of future species compositionin changing environments

5 Conclusions

The species diversity of trees varied across vegetation types inthe Western Ghats landscape Rarefaction curves show thatspecies diversity is highest in SEMI and EVER and lowest inWOOD while species abundance is highest in MONT Vege-tation types of study area are in heterogeneous in distributionThere were large differences in species composition of adulttrees and regenerating individuals in the disturbed vegetationtypes as compared to undisturbed stands The present studyreveals that the anthropogenic disturbance causes disruptionof forest structure and change in species composition whichultimately leads to reduction of tree species richness andabundance which are the major attributes of forests Newrecruits were found in all vegetation types indicating thattheywere not headed to extinction however disturbed standsmay move to new species compositions in the future

Acknowledgments

The authors are thankful to the Ministry of Environmentand Forests for financial support and the Vice Chancellorof University of Delhi and the Director of Kerala ForestResearch Institute for facilities provided The first authorwould like to thank Professor C R Babu for facilities andencouragement The authors are very much obliged to allmembers of the Cholanaikkan tribe who helped duringthe field survey The Kerala Forest Department provided alllogistical support for the floristic and ecological survey of theforest area (trees haminus1) in three different growth phases of sixvegetation

References

[1] M A Huston Biological Diversity The Coexistence of Species inChanging Landscapes Cambridge University Press CambridgeUK 1994

[2] T C Whitmore An Introduction to Tropical Rain ForestsOxfordUniversity Press NewYork NYUSA 2nd edition 1998

[3] M L Khan S Menon and K S Bawa ldquoEffectiveness of theprotected area network in biodiversity conservation a case-study of Meghalaya staterdquo Biodiversity and Conservation vol 6no 6 pp 853ndash868 1997

[4] C M Pringle ldquoNutrient spatial heterogeneity effects on com-munity structure physiognomy and diversity of stream algaerdquoEcology vol 71 no 3 pp 905ndash920 1990

[5] M Parviainen M Marmion M Luoto W Thuiller and RK Heikkinen ldquoUsing summed individual species models andstate-of-the-art modelling techniques to identify threatenedplant species hotspotsrdquo Biological Conservation vol 142 no 11pp 2501ndash2509 2009

[6] J S Singh S P Singh A K Saxena and Y S Ravat ldquoThe forestvegetation of Silent Valleyrdquo in Tropical Rain Forests The LeedsSymposium pp 25ndash52 1984

[7] A O Varghese ldquoAssessment of biodiversity of PepparaWildlifeSanctuary Trivandrum District Keralardquo Journal of Economicand Taxonomic Botany vol 23 pp 117ndash127 1998

[8] M A Suraj Phytosociological and vagetation mapping at chim-mony wildlife Sanctuary (Kerala) using remote sensing technique[PhD thesis] FRI University Dehradun India 1997

[9] N Parthasarathy Studies on the vacular flora structure andnutrient cycling in Kalakad Reserve Forest Western Ghats TamilNadu [PhD thesis] University of Madras Tamil Nadu India1986

[10] S N Rai and J Proctor ldquoEcological studies on four rainforests in Karnataka India environment forest structure andvegetationrdquo Journal of Vegetation Science vol 1 pp 609ndash6141986

[11] U M Chadrashekara A R R Menon K K N Nair NSasidharan and K Swarupanandan ldquoEvaluating plant diversityin different forest types of Kerala by laying out permanent sam-ple plotsrdquo KFRI Research Report 156 Kerala Forest ResearchInstitute Peechi India 1998

[12] C S Jha and J S Singh ldquoComposition and dynamics of drytropical Forest in relation to soil texturerdquo Journal of VegetationScience vol 1 no 5 pp 609ndash614 1990

[13] NVisalakshi ldquoVegetation analysis of two tropical dry evergreenforests in southern IndiardquoTropical Ecology vol 36 no 1 pp 117ndash127 1995

ISRN Ecology 13

[14] T Ganesh R Ganesan M Soubadra Devy P Davidar and K SBawa ldquoAssessment of plant biodiversity at amid-elevation ever-green forest of Kalakad-Mundanthurai Tiger Reserve WesternGhats Indiardquo Current Science vol 71 no 5 pp 379ndash392 1996

[15] S M Sundarapandian and P S Swamy ldquoForest ecosystemstructure and composition along an altitudinal gradient in theWestern Ghats South Indiardquo Journal of Tropical Forest Sciencevol 12 no 1 pp 104ndash123 2000

[16] K Swarupanandan N Sasidharan K C Chacko and SChanduBasha ldquoFloristic and ecological studies on the Sholasof Idukki Districtrdquo in Shola Forests of Kerala Environmentand Biodiverstiy K K N Nair S K Khanduri and K Bala-subramaniayan Eds pp 259ndash286 Kerala Forest DeparmentThiruvanathapuram Kerala Forest Research Institute PeechiIndia 2001

[17] R W Thorington S Tannenbaum A Tarak and R RudranldquoDistribution of trees in Baro Colorado Islands a hectaresamplerdquo in The Ecology of a Tropical Forest-Seasonal Rhythmsand Long-term Changes E G Leigh Jr A S Rand and D MWindsor Eds Smithsonian Institute Press Washington DCUSA 1982

[18] S P Hubbell and R B Foster ldquoDiversity of canopy speciesin a neotropical forest and implications for conservationrdquo inTropical Rain Forest Ecology and Management S L Sutton TCWhitmore andA C Chadwick Eds Blackwell Oxford UK1983

[19] D G Campbell D C Daly G T Prance and U N MacielldquoQuantitative ecological inventory of terra firme and varzeatropical forest on the Rio Xingu Brazilian Amazonrdquo Brittoniavol 38 no 4 pp 369ndash393 1986

[20] S Itow ldquoSpecies diversity of equatorial insular forests on Ponapeand Kosrae Micronesiardquo Ecological Research vol 1 no 2 pp223ndash227 1986

[21] C C Ho D M Newbery and M E D Poore ldquoForestcomposition and inferred dynamics in Jengka Forest ReserveMalaysiardquo Journal of Tropical Ecology vol 3 no 1 pp 25ndash561987

[22] J Proctor Y F Lee A M Langley W R C Munro and TNelson ldquoEcological studies onGunung Silam a small ultrabasicmountain Sabah Malaysiardquo Journal of Ecology vol 74 pp 455ndash463 1988

[23] F R Swan Jr ldquoTree distribution patterns in the Bukittimahnature reserve Singaporerdquo Gardens Bulletin vol 41 pp 59ndash811988

[24] A Heaney and J Proctor ldquoPreliminary studies on foreststructure and floristics on Volcan Barva Costa Ricardquo Journalof Tropical Ecology vol 6 no 3 pp 307ndash320 1990

[25] T Jaffre and J M Veillon ldquoEtude floristique et structuralede deux forets denses humides sur roches ultrabasiques enNouvelle- Caledonierdquo Bulletin du Museum National drsquoHistoireNaturelle vol 12 pp 243ndash273 1990

[26] MMosango ldquoContribution ldquoA lrsquoetude botanic biogeo 1rdquo ecosys-tem Foret en region equatorial (Ile KongoloZaire)rdquo BelgiumJournal of Botany vol 124 pp 167ndash194 1991

[27] M Cao and J Zhang ldquoTree species diversity of tropical forestvegetation in Xishuangbanna SW Chinardquo Biodiversity andConservation vol 6 no 7 pp 995ndash1006 1997

[28] C S Jha L Goparaju A Tripathi B Gharai A S Raghubanshiand J S Singh ldquoForest fragmentation and its impact onspecies diversity an analysis using remote sensing and GISrdquoBiodiversity and Conservation vol 14 no 7 pp 1681ndash1698 2005

[29] P S Roy C B S Dutt and P K Joshi ldquoTropical forest resourceassessment and monitoringrdquo Tropical Ecology vol 43 no 1 pp21ndash37 2002

[30] R Sagar A S Raghubanshi and J S Singh ldquoAsymptoticmodelsof species-area curve for measuring diversity of dry tropicalforest tree speciesrdquo Current Science vol 84 no 12 pp 1555ndash1560 2003

[31] R Sukumar H S Dattaraja H S Suresh et al ldquoLong-termmonitoring of vegetation in a tropical deciduous forest inMudumalai southern Indiardquo Current Science vol 62 pp 608ndash616 1992

[32] UMChandrashekara and P S Ramakrishnan ldquoVegetation andgap dynamics of a tropical wet evergreen forest in the WesternGhats of Kerala Indiardquo Journal of Tropical Ecology vol 10 no3 pp 337ndash354 1994

[33] T Ganesh R Ganesan M Soubadra Devy P Davidar and K SBawa ldquoAssessment of plant biodiversity at amid-elevation ever-green forest of Kalakad-Mundanthurai Tiger Reserve WesternGhats Indiardquo Current Science vol 71 no 5 pp 379ndash392 1996

[34] J P Pascal and R Pelissier ldquoStructure and floristic compositionof a tropical evergreen forest in south-west Indiardquo Journal ofTropical Ecology vol 12 no 2 pp 191ndash210 1996

[35] N Ayyappan and N Parthasarathy ldquoBiodiversity inventory oftrees in a large-scale permanent plot of tropical evergreen forestat Varagalaiar Anamalais Western Ghats Indiardquo Biodiversityand Conservation vol 8 no 11 pp 1533ndash1554 1999

[36] A Kumar B G Marcot and A Saxena ldquoTree species diversityand distribution patterns in tropical forests of Garo HillsrdquoCurrent Science vol 91 no 10 pp 1370ndash1381 2006

[37] N Parthasarathy ldquoTree diversity and distribution in undis-turbed and human-impacted sites of tropical wet evergreenforest in southern Western Ghats Indiardquo Biodiversity andConservation vol 8 no 10 pp 1365ndash1381 1999

[38] M L Khan J P N Rai and R S Tripathi ldquoPopulation structureof some tree species in disturbed and protected subtropicalforests of north-east Indiardquo Acta Oecologica vol 8 no 3 pp247ndash255 1987

[39] R S Tripathi and M L Khan ldquoRegeneration pattern andpopulation structure of trees in subtropical forest of North EastIndiardquo in Tropical Ecosystem-Ecology and Management K PSingh and J S Singh Eds pp 431ndash441 Wiley Eastern LimitedNew Delhi India 1992

[40] A E Scholl and A H Taylor ldquoRegeneration patterns in old-growth red fir-western white pine forests in the northern SierraNevada Lake Tahoe USArdquo Forest Ecology and Managementvol 235 no 1ndash3 pp 143ndash154 2006

[41] D A Clark ldquoRegeneration of canopy trees in tropical wetforestsrdquo Trends in Ecology and Evolution vol 1 no 6 pp 150ndash154 1986

[42] P C J Barker and J B Kirkpatrick ldquoPhyllocladus aspleniifoliusvariability in the population structure the regeneration nicheand dispersion patterns in Tasmanian forestsrdquo Australian Jour-nal of Botany vol 42 no 2 pp 163ndash190 1994

[43] C K Augspurger ldquoSeedling survival of tropical tree speciesinteractions of dispersal distance light-gaps and pathogensrdquoEcology vol 65 no 6 pp 1705ndash1712 1984

[44] O L Phillips ldquoLong-term environmental change in tropicalforests increasing tree turnoverrdquo Environmental Conservationvol 23 no 3 pp 235ndash248 1996

[45] Ministry of Environment and Forests ldquoPlant discoveries 2011newgenera species andnew recordsrdquo Botanical Survey of IndiaMinistry of Environment and Forests New Delhi India 2012

14 ISRN Ecology

[46] ldquoWeblink 2007rdquo httpwwwbiodiversityhotspotsorgxphot-spotshotspots by region

[47] D Mueller-Dombois and H Ellenberg Aims and Methods ofPlant Ecology John Wiley amp Sons New York NY USA 1974

[48] K K N Nair and R Jayakumar ldquoPhytogeography endemismand affinities of the flora of NewAmarambalamReserve Forestsin theWesternGhats of Indiardquo Indian Journal of Forestry vol 31pp 85ndash94 2008

[49] A E Magurran Ecological Diversity and Its MeasurementCroom Helm Ltd London UK 1988

[50] C Raunkiaer The Life Forms of Plants and Statistical PlantGeography Clarendon Press Oxford UK 1934

[51] B Rice andMWestoby ldquoPlant species richness at the 01 hectarescale in Australian vegetation compared to other continentsrdquoVegetatio vol 52 no 3 pp 129ndash140 1983

[52] SM Scheiner ldquoSix types of species-area curvesrdquoGlobal Ecologyand Biogeography vol 12 no 6 pp 441ndash447 2003

[53] H G Jones Plants and Microclimate Cambridge UniversityPress Cambridge UK 1983

[54] N C Nair The Southern Western Ghats A Biodiversity Con-servation Plan Indian National Trust for Arts and CulturalHeritage New Delhi India 1991

[55] AHGentry ldquoChanges in plant community diversity and floris-tic composition on environmental and geographical gradientrdquoAnnals of the Missouri Botanical Garden vol 75 no 1 pp 1ndash341988

[56] T CWhitmore Tropical Rain Forests of the Far East ClarendonPress Oxford UK 1984

[57] N V L Brokaw ldquoGap-phase regeneration of three pioneer treespecies in a tropical forestrdquo Journal of Ecology vol 75 no 1 pp9ndash19 1987

[58] S Itow and D Mueller-Dombois ldquoPopulation structure stand-level dieback and recovery of Scalesia pedunculata forest in theGalapagos Islandsrdquo Ecological Research vol 3 no 3 pp 333ndash339 1988

[59] T CWhitmore ldquoA review of some aspects of tropical rainforestseedling ecology with suggestions for further enquiryrdquo inEcology of Tropical Forest Tree Seedlings M D Swaine Ed pp3ndash39 UNESCOParthenon Paris France 1996

Submit your manuscripts athttpwwwhindawicom

Forestry ResearchInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Environmental and Public Health

Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

EcosystemsJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

MeteorologyAdvances in

EcologyInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Marine BiologyJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom

Applied ampEnvironmentalSoil Science

Volume 2014

Advances in

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Environmental Chemistry

Atmospheric SciencesInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Waste ManagementJournal of

Hindawi Publishing Corporation httpwwwhindawicom Volume 2014

International Journal of

Geophysics

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Geological ResearchJournal of

EarthquakesJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

BiodiversityInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

ScientificaHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

OceanographyInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Journal of Computational Environmental SciencesHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

ClimatologyJournal of

Page 12: Research Article Species Diversity and Tree Regeneration ...downloads.hindawi.com/archive/2013/890862.pdf · Species Diversity and Tree Regeneration Patterns in Tropical Forests of

12 ISRN Ecology

relatively undisturbed or less disturbed conditions in thestands The high annual precipitation rate and optimumtemperature of EVER may have contributed to high treegrowth rate and higher tree basal area

42 Regeneration All other vegetation types had betterregeneration than DECI In WOOD the transition rate ofstems from small girth classes to larger girth classes was lowPoor tree regeneration in DECI and WOOD can probablybe attributed to fuel wood collection frequent fires andgrazing by cattle In all forest types 29ndash47 of tree specieswere present in all three growth phases other species werepresent in either one or two growth phases Dominant speciesoccurred in all girth classes of vegetation types other thanWOOD in whichmost trees were in the smaller girth classesThere were more large trees in vegetation types like SEMIand EVER and in these sapling and seedling densities wereadequate for restocking the complement of canopy trees

Change in species composition across mature and regen-erating tree phases was more frequent in disturbed foresttypes like DECI and WOOD In some cases the dominantspecies in adult and seedling stages were quite differentin these two disturbed forest types Our results are notcongruent with observationsmade in northeastern India [39]where tree seedling survival rate increases with increasingforest disturbance We found species without regeneratingphases these are unlikely to persist Others that occurred onlyin seedling and sapling stages were new entrants to the forestspecies complement These are examples of discontinuouspopulation structures Such structures occur in a number ofother tropical countries [57ndash59] The dominant species in aforest stand is generally present in all size classes [38] Thesize class structures of trees indicate the probability of speciespersistence into the future this information is very valuablein the design of management strategies aiming to improvestand structure and species diversity Changes in speciescomposition and recruitment of new species in differentvegetation types are indicative of future species compositionin changing environments

5 Conclusions

The species diversity of trees varied across vegetation types inthe Western Ghats landscape Rarefaction curves show thatspecies diversity is highest in SEMI and EVER and lowest inWOOD while species abundance is highest in MONT Vege-tation types of study area are in heterogeneous in distributionThere were large differences in species composition of adulttrees and regenerating individuals in the disturbed vegetationtypes as compared to undisturbed stands The present studyreveals that the anthropogenic disturbance causes disruptionof forest structure and change in species composition whichultimately leads to reduction of tree species richness andabundance which are the major attributes of forests Newrecruits were found in all vegetation types indicating thattheywere not headed to extinction however disturbed standsmay move to new species compositions in the future

Acknowledgments

The authors are thankful to the Ministry of Environmentand Forests for financial support and the Vice Chancellorof University of Delhi and the Director of Kerala ForestResearch Institute for facilities provided The first authorwould like to thank Professor C R Babu for facilities andencouragement The authors are very much obliged to allmembers of the Cholanaikkan tribe who helped duringthe field survey The Kerala Forest Department provided alllogistical support for the floristic and ecological survey of theforest area (trees haminus1) in three different growth phases of sixvegetation

References

[1] M A Huston Biological Diversity The Coexistence of Species inChanging Landscapes Cambridge University Press CambridgeUK 1994

[2] T C Whitmore An Introduction to Tropical Rain ForestsOxfordUniversity Press NewYork NYUSA 2nd edition 1998

[3] M L Khan S Menon and K S Bawa ldquoEffectiveness of theprotected area network in biodiversity conservation a case-study of Meghalaya staterdquo Biodiversity and Conservation vol 6no 6 pp 853ndash868 1997

[4] C M Pringle ldquoNutrient spatial heterogeneity effects on com-munity structure physiognomy and diversity of stream algaerdquoEcology vol 71 no 3 pp 905ndash920 1990

[5] M Parviainen M Marmion M Luoto W Thuiller and RK Heikkinen ldquoUsing summed individual species models andstate-of-the-art modelling techniques to identify threatenedplant species hotspotsrdquo Biological Conservation vol 142 no 11pp 2501ndash2509 2009

[6] J S Singh S P Singh A K Saxena and Y S Ravat ldquoThe forestvegetation of Silent Valleyrdquo in Tropical Rain Forests The LeedsSymposium pp 25ndash52 1984

[7] A O Varghese ldquoAssessment of biodiversity of PepparaWildlifeSanctuary Trivandrum District Keralardquo Journal of Economicand Taxonomic Botany vol 23 pp 117ndash127 1998

[8] M A Suraj Phytosociological and vagetation mapping at chim-mony wildlife Sanctuary (Kerala) using remote sensing technique[PhD thesis] FRI University Dehradun India 1997

[9] N Parthasarathy Studies on the vacular flora structure andnutrient cycling in Kalakad Reserve Forest Western Ghats TamilNadu [PhD thesis] University of Madras Tamil Nadu India1986

[10] S N Rai and J Proctor ldquoEcological studies on four rainforests in Karnataka India environment forest structure andvegetationrdquo Journal of Vegetation Science vol 1 pp 609ndash6141986

[11] U M Chadrashekara A R R Menon K K N Nair NSasidharan and K Swarupanandan ldquoEvaluating plant diversityin different forest types of Kerala by laying out permanent sam-ple plotsrdquo KFRI Research Report 156 Kerala Forest ResearchInstitute Peechi India 1998

[12] C S Jha and J S Singh ldquoComposition and dynamics of drytropical Forest in relation to soil texturerdquo Journal of VegetationScience vol 1 no 5 pp 609ndash614 1990

[13] NVisalakshi ldquoVegetation analysis of two tropical dry evergreenforests in southern IndiardquoTropical Ecology vol 36 no 1 pp 117ndash127 1995

ISRN Ecology 13

[14] T Ganesh R Ganesan M Soubadra Devy P Davidar and K SBawa ldquoAssessment of plant biodiversity at amid-elevation ever-green forest of Kalakad-Mundanthurai Tiger Reserve WesternGhats Indiardquo Current Science vol 71 no 5 pp 379ndash392 1996

[15] S M Sundarapandian and P S Swamy ldquoForest ecosystemstructure and composition along an altitudinal gradient in theWestern Ghats South Indiardquo Journal of Tropical Forest Sciencevol 12 no 1 pp 104ndash123 2000

[16] K Swarupanandan N Sasidharan K C Chacko and SChanduBasha ldquoFloristic and ecological studies on the Sholasof Idukki Districtrdquo in Shola Forests of Kerala Environmentand Biodiverstiy K K N Nair S K Khanduri and K Bala-subramaniayan Eds pp 259ndash286 Kerala Forest DeparmentThiruvanathapuram Kerala Forest Research Institute PeechiIndia 2001

[17] R W Thorington S Tannenbaum A Tarak and R RudranldquoDistribution of trees in Baro Colorado Islands a hectaresamplerdquo in The Ecology of a Tropical Forest-Seasonal Rhythmsand Long-term Changes E G Leigh Jr A S Rand and D MWindsor Eds Smithsonian Institute Press Washington DCUSA 1982

[18] S P Hubbell and R B Foster ldquoDiversity of canopy speciesin a neotropical forest and implications for conservationrdquo inTropical Rain Forest Ecology and Management S L Sutton TCWhitmore andA C Chadwick Eds Blackwell Oxford UK1983

[19] D G Campbell D C Daly G T Prance and U N MacielldquoQuantitative ecological inventory of terra firme and varzeatropical forest on the Rio Xingu Brazilian Amazonrdquo Brittoniavol 38 no 4 pp 369ndash393 1986

[20] S Itow ldquoSpecies diversity of equatorial insular forests on Ponapeand Kosrae Micronesiardquo Ecological Research vol 1 no 2 pp223ndash227 1986

[21] C C Ho D M Newbery and M E D Poore ldquoForestcomposition and inferred dynamics in Jengka Forest ReserveMalaysiardquo Journal of Tropical Ecology vol 3 no 1 pp 25ndash561987

[22] J Proctor Y F Lee A M Langley W R C Munro and TNelson ldquoEcological studies onGunung Silam a small ultrabasicmountain Sabah Malaysiardquo Journal of Ecology vol 74 pp 455ndash463 1988

[23] F R Swan Jr ldquoTree distribution patterns in the Bukittimahnature reserve Singaporerdquo Gardens Bulletin vol 41 pp 59ndash811988

[24] A Heaney and J Proctor ldquoPreliminary studies on foreststructure and floristics on Volcan Barva Costa Ricardquo Journalof Tropical Ecology vol 6 no 3 pp 307ndash320 1990

[25] T Jaffre and J M Veillon ldquoEtude floristique et structuralede deux forets denses humides sur roches ultrabasiques enNouvelle- Caledonierdquo Bulletin du Museum National drsquoHistoireNaturelle vol 12 pp 243ndash273 1990

[26] MMosango ldquoContribution ldquoA lrsquoetude botanic biogeo 1rdquo ecosys-tem Foret en region equatorial (Ile KongoloZaire)rdquo BelgiumJournal of Botany vol 124 pp 167ndash194 1991

[27] M Cao and J Zhang ldquoTree species diversity of tropical forestvegetation in Xishuangbanna SW Chinardquo Biodiversity andConservation vol 6 no 7 pp 995ndash1006 1997

[28] C S Jha L Goparaju A Tripathi B Gharai A S Raghubanshiand J S Singh ldquoForest fragmentation and its impact onspecies diversity an analysis using remote sensing and GISrdquoBiodiversity and Conservation vol 14 no 7 pp 1681ndash1698 2005

[29] P S Roy C B S Dutt and P K Joshi ldquoTropical forest resourceassessment and monitoringrdquo Tropical Ecology vol 43 no 1 pp21ndash37 2002

[30] R Sagar A S Raghubanshi and J S Singh ldquoAsymptoticmodelsof species-area curve for measuring diversity of dry tropicalforest tree speciesrdquo Current Science vol 84 no 12 pp 1555ndash1560 2003

[31] R Sukumar H S Dattaraja H S Suresh et al ldquoLong-termmonitoring of vegetation in a tropical deciduous forest inMudumalai southern Indiardquo Current Science vol 62 pp 608ndash616 1992

[32] UMChandrashekara and P S Ramakrishnan ldquoVegetation andgap dynamics of a tropical wet evergreen forest in the WesternGhats of Kerala Indiardquo Journal of Tropical Ecology vol 10 no3 pp 337ndash354 1994

[33] T Ganesh R Ganesan M Soubadra Devy P Davidar and K SBawa ldquoAssessment of plant biodiversity at amid-elevation ever-green forest of Kalakad-Mundanthurai Tiger Reserve WesternGhats Indiardquo Current Science vol 71 no 5 pp 379ndash392 1996

[34] J P Pascal and R Pelissier ldquoStructure and floristic compositionof a tropical evergreen forest in south-west Indiardquo Journal ofTropical Ecology vol 12 no 2 pp 191ndash210 1996

[35] N Ayyappan and N Parthasarathy ldquoBiodiversity inventory oftrees in a large-scale permanent plot of tropical evergreen forestat Varagalaiar Anamalais Western Ghats Indiardquo Biodiversityand Conservation vol 8 no 11 pp 1533ndash1554 1999

[36] A Kumar B G Marcot and A Saxena ldquoTree species diversityand distribution patterns in tropical forests of Garo HillsrdquoCurrent Science vol 91 no 10 pp 1370ndash1381 2006

[37] N Parthasarathy ldquoTree diversity and distribution in undis-turbed and human-impacted sites of tropical wet evergreenforest in southern Western Ghats Indiardquo Biodiversity andConservation vol 8 no 10 pp 1365ndash1381 1999

[38] M L Khan J P N Rai and R S Tripathi ldquoPopulation structureof some tree species in disturbed and protected subtropicalforests of north-east Indiardquo Acta Oecologica vol 8 no 3 pp247ndash255 1987

[39] R S Tripathi and M L Khan ldquoRegeneration pattern andpopulation structure of trees in subtropical forest of North EastIndiardquo in Tropical Ecosystem-Ecology and Management K PSingh and J S Singh Eds pp 431ndash441 Wiley Eastern LimitedNew Delhi India 1992

[40] A E Scholl and A H Taylor ldquoRegeneration patterns in old-growth red fir-western white pine forests in the northern SierraNevada Lake Tahoe USArdquo Forest Ecology and Managementvol 235 no 1ndash3 pp 143ndash154 2006

[41] D A Clark ldquoRegeneration of canopy trees in tropical wetforestsrdquo Trends in Ecology and Evolution vol 1 no 6 pp 150ndash154 1986

[42] P C J Barker and J B Kirkpatrick ldquoPhyllocladus aspleniifoliusvariability in the population structure the regeneration nicheand dispersion patterns in Tasmanian forestsrdquo Australian Jour-nal of Botany vol 42 no 2 pp 163ndash190 1994

[43] C K Augspurger ldquoSeedling survival of tropical tree speciesinteractions of dispersal distance light-gaps and pathogensrdquoEcology vol 65 no 6 pp 1705ndash1712 1984

[44] O L Phillips ldquoLong-term environmental change in tropicalforests increasing tree turnoverrdquo Environmental Conservationvol 23 no 3 pp 235ndash248 1996

[45] Ministry of Environment and Forests ldquoPlant discoveries 2011newgenera species andnew recordsrdquo Botanical Survey of IndiaMinistry of Environment and Forests New Delhi India 2012

14 ISRN Ecology

[46] ldquoWeblink 2007rdquo httpwwwbiodiversityhotspotsorgxphot-spotshotspots by region

[47] D Mueller-Dombois and H Ellenberg Aims and Methods ofPlant Ecology John Wiley amp Sons New York NY USA 1974

[48] K K N Nair and R Jayakumar ldquoPhytogeography endemismand affinities of the flora of NewAmarambalamReserve Forestsin theWesternGhats of Indiardquo Indian Journal of Forestry vol 31pp 85ndash94 2008

[49] A E Magurran Ecological Diversity and Its MeasurementCroom Helm Ltd London UK 1988

[50] C Raunkiaer The Life Forms of Plants and Statistical PlantGeography Clarendon Press Oxford UK 1934

[51] B Rice andMWestoby ldquoPlant species richness at the 01 hectarescale in Australian vegetation compared to other continentsrdquoVegetatio vol 52 no 3 pp 129ndash140 1983

[52] SM Scheiner ldquoSix types of species-area curvesrdquoGlobal Ecologyand Biogeography vol 12 no 6 pp 441ndash447 2003

[53] H G Jones Plants and Microclimate Cambridge UniversityPress Cambridge UK 1983

[54] N C Nair The Southern Western Ghats A Biodiversity Con-servation Plan Indian National Trust for Arts and CulturalHeritage New Delhi India 1991

[55] AHGentry ldquoChanges in plant community diversity and floris-tic composition on environmental and geographical gradientrdquoAnnals of the Missouri Botanical Garden vol 75 no 1 pp 1ndash341988

[56] T CWhitmore Tropical Rain Forests of the Far East ClarendonPress Oxford UK 1984

[57] N V L Brokaw ldquoGap-phase regeneration of three pioneer treespecies in a tropical forestrdquo Journal of Ecology vol 75 no 1 pp9ndash19 1987

[58] S Itow and D Mueller-Dombois ldquoPopulation structure stand-level dieback and recovery of Scalesia pedunculata forest in theGalapagos Islandsrdquo Ecological Research vol 3 no 3 pp 333ndash339 1988

[59] T CWhitmore ldquoA review of some aspects of tropical rainforestseedling ecology with suggestions for further enquiryrdquo inEcology of Tropical Forest Tree Seedlings M D Swaine Ed pp3ndash39 UNESCOParthenon Paris France 1996

Submit your manuscripts athttpwwwhindawicom

Forestry ResearchInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Environmental and Public Health

Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

EcosystemsJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

MeteorologyAdvances in

EcologyInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Marine BiologyJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom

Applied ampEnvironmentalSoil Science

Volume 2014

Advances in

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Environmental Chemistry

Atmospheric SciencesInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Waste ManagementJournal of

Hindawi Publishing Corporation httpwwwhindawicom Volume 2014

International Journal of

Geophysics

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Geological ResearchJournal of

EarthquakesJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

BiodiversityInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

ScientificaHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

OceanographyInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Journal of Computational Environmental SciencesHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

ClimatologyJournal of

Page 13: Research Article Species Diversity and Tree Regeneration ...downloads.hindawi.com/archive/2013/890862.pdf · Species Diversity and Tree Regeneration Patterns in Tropical Forests of

ISRN Ecology 13

[14] T Ganesh R Ganesan M Soubadra Devy P Davidar and K SBawa ldquoAssessment of plant biodiversity at amid-elevation ever-green forest of Kalakad-Mundanthurai Tiger Reserve WesternGhats Indiardquo Current Science vol 71 no 5 pp 379ndash392 1996

[15] S M Sundarapandian and P S Swamy ldquoForest ecosystemstructure and composition along an altitudinal gradient in theWestern Ghats South Indiardquo Journal of Tropical Forest Sciencevol 12 no 1 pp 104ndash123 2000

[16] K Swarupanandan N Sasidharan K C Chacko and SChanduBasha ldquoFloristic and ecological studies on the Sholasof Idukki Districtrdquo in Shola Forests of Kerala Environmentand Biodiverstiy K K N Nair S K Khanduri and K Bala-subramaniayan Eds pp 259ndash286 Kerala Forest DeparmentThiruvanathapuram Kerala Forest Research Institute PeechiIndia 2001

[17] R W Thorington S Tannenbaum A Tarak and R RudranldquoDistribution of trees in Baro Colorado Islands a hectaresamplerdquo in The Ecology of a Tropical Forest-Seasonal Rhythmsand Long-term Changes E G Leigh Jr A S Rand and D MWindsor Eds Smithsonian Institute Press Washington DCUSA 1982

[18] S P Hubbell and R B Foster ldquoDiversity of canopy speciesin a neotropical forest and implications for conservationrdquo inTropical Rain Forest Ecology and Management S L Sutton TCWhitmore andA C Chadwick Eds Blackwell Oxford UK1983

[19] D G Campbell D C Daly G T Prance and U N MacielldquoQuantitative ecological inventory of terra firme and varzeatropical forest on the Rio Xingu Brazilian Amazonrdquo Brittoniavol 38 no 4 pp 369ndash393 1986

[20] S Itow ldquoSpecies diversity of equatorial insular forests on Ponapeand Kosrae Micronesiardquo Ecological Research vol 1 no 2 pp223ndash227 1986

[21] C C Ho D M Newbery and M E D Poore ldquoForestcomposition and inferred dynamics in Jengka Forest ReserveMalaysiardquo Journal of Tropical Ecology vol 3 no 1 pp 25ndash561987

[22] J Proctor Y F Lee A M Langley W R C Munro and TNelson ldquoEcological studies onGunung Silam a small ultrabasicmountain Sabah Malaysiardquo Journal of Ecology vol 74 pp 455ndash463 1988

[23] F R Swan Jr ldquoTree distribution patterns in the Bukittimahnature reserve Singaporerdquo Gardens Bulletin vol 41 pp 59ndash811988

[24] A Heaney and J Proctor ldquoPreliminary studies on foreststructure and floristics on Volcan Barva Costa Ricardquo Journalof Tropical Ecology vol 6 no 3 pp 307ndash320 1990

[25] T Jaffre and J M Veillon ldquoEtude floristique et structuralede deux forets denses humides sur roches ultrabasiques enNouvelle- Caledonierdquo Bulletin du Museum National drsquoHistoireNaturelle vol 12 pp 243ndash273 1990

[26] MMosango ldquoContribution ldquoA lrsquoetude botanic biogeo 1rdquo ecosys-tem Foret en region equatorial (Ile KongoloZaire)rdquo BelgiumJournal of Botany vol 124 pp 167ndash194 1991

[27] M Cao and J Zhang ldquoTree species diversity of tropical forestvegetation in Xishuangbanna SW Chinardquo Biodiversity andConservation vol 6 no 7 pp 995ndash1006 1997

[28] C S Jha L Goparaju A Tripathi B Gharai A S Raghubanshiand J S Singh ldquoForest fragmentation and its impact onspecies diversity an analysis using remote sensing and GISrdquoBiodiversity and Conservation vol 14 no 7 pp 1681ndash1698 2005

[29] P S Roy C B S Dutt and P K Joshi ldquoTropical forest resourceassessment and monitoringrdquo Tropical Ecology vol 43 no 1 pp21ndash37 2002

[30] R Sagar A S Raghubanshi and J S Singh ldquoAsymptoticmodelsof species-area curve for measuring diversity of dry tropicalforest tree speciesrdquo Current Science vol 84 no 12 pp 1555ndash1560 2003

[31] R Sukumar H S Dattaraja H S Suresh et al ldquoLong-termmonitoring of vegetation in a tropical deciduous forest inMudumalai southern Indiardquo Current Science vol 62 pp 608ndash616 1992

[32] UMChandrashekara and P S Ramakrishnan ldquoVegetation andgap dynamics of a tropical wet evergreen forest in the WesternGhats of Kerala Indiardquo Journal of Tropical Ecology vol 10 no3 pp 337ndash354 1994

[33] T Ganesh R Ganesan M Soubadra Devy P Davidar and K SBawa ldquoAssessment of plant biodiversity at amid-elevation ever-green forest of Kalakad-Mundanthurai Tiger Reserve WesternGhats Indiardquo Current Science vol 71 no 5 pp 379ndash392 1996

[34] J P Pascal and R Pelissier ldquoStructure and floristic compositionof a tropical evergreen forest in south-west Indiardquo Journal ofTropical Ecology vol 12 no 2 pp 191ndash210 1996

[35] N Ayyappan and N Parthasarathy ldquoBiodiversity inventory oftrees in a large-scale permanent plot of tropical evergreen forestat Varagalaiar Anamalais Western Ghats Indiardquo Biodiversityand Conservation vol 8 no 11 pp 1533ndash1554 1999

[36] A Kumar B G Marcot and A Saxena ldquoTree species diversityand distribution patterns in tropical forests of Garo HillsrdquoCurrent Science vol 91 no 10 pp 1370ndash1381 2006

[37] N Parthasarathy ldquoTree diversity and distribution in undis-turbed and human-impacted sites of tropical wet evergreenforest in southern Western Ghats Indiardquo Biodiversity andConservation vol 8 no 10 pp 1365ndash1381 1999

[38] M L Khan J P N Rai and R S Tripathi ldquoPopulation structureof some tree species in disturbed and protected subtropicalforests of north-east Indiardquo Acta Oecologica vol 8 no 3 pp247ndash255 1987

[39] R S Tripathi and M L Khan ldquoRegeneration pattern andpopulation structure of trees in subtropical forest of North EastIndiardquo in Tropical Ecosystem-Ecology and Management K PSingh and J S Singh Eds pp 431ndash441 Wiley Eastern LimitedNew Delhi India 1992

[40] A E Scholl and A H Taylor ldquoRegeneration patterns in old-growth red fir-western white pine forests in the northern SierraNevada Lake Tahoe USArdquo Forest Ecology and Managementvol 235 no 1ndash3 pp 143ndash154 2006

[41] D A Clark ldquoRegeneration of canopy trees in tropical wetforestsrdquo Trends in Ecology and Evolution vol 1 no 6 pp 150ndash154 1986

[42] P C J Barker and J B Kirkpatrick ldquoPhyllocladus aspleniifoliusvariability in the population structure the regeneration nicheand dispersion patterns in Tasmanian forestsrdquo Australian Jour-nal of Botany vol 42 no 2 pp 163ndash190 1994

[43] C K Augspurger ldquoSeedling survival of tropical tree speciesinteractions of dispersal distance light-gaps and pathogensrdquoEcology vol 65 no 6 pp 1705ndash1712 1984

[44] O L Phillips ldquoLong-term environmental change in tropicalforests increasing tree turnoverrdquo Environmental Conservationvol 23 no 3 pp 235ndash248 1996

[45] Ministry of Environment and Forests ldquoPlant discoveries 2011newgenera species andnew recordsrdquo Botanical Survey of IndiaMinistry of Environment and Forests New Delhi India 2012

14 ISRN Ecology

[46] ldquoWeblink 2007rdquo httpwwwbiodiversityhotspotsorgxphot-spotshotspots by region

[47] D Mueller-Dombois and H Ellenberg Aims and Methods ofPlant Ecology John Wiley amp Sons New York NY USA 1974

[48] K K N Nair and R Jayakumar ldquoPhytogeography endemismand affinities of the flora of NewAmarambalamReserve Forestsin theWesternGhats of Indiardquo Indian Journal of Forestry vol 31pp 85ndash94 2008

[49] A E Magurran Ecological Diversity and Its MeasurementCroom Helm Ltd London UK 1988

[50] C Raunkiaer The Life Forms of Plants and Statistical PlantGeography Clarendon Press Oxford UK 1934

[51] B Rice andMWestoby ldquoPlant species richness at the 01 hectarescale in Australian vegetation compared to other continentsrdquoVegetatio vol 52 no 3 pp 129ndash140 1983

[52] SM Scheiner ldquoSix types of species-area curvesrdquoGlobal Ecologyand Biogeography vol 12 no 6 pp 441ndash447 2003

[53] H G Jones Plants and Microclimate Cambridge UniversityPress Cambridge UK 1983

[54] N C Nair The Southern Western Ghats A Biodiversity Con-servation Plan Indian National Trust for Arts and CulturalHeritage New Delhi India 1991

[55] AHGentry ldquoChanges in plant community diversity and floris-tic composition on environmental and geographical gradientrdquoAnnals of the Missouri Botanical Garden vol 75 no 1 pp 1ndash341988

[56] T CWhitmore Tropical Rain Forests of the Far East ClarendonPress Oxford UK 1984

[57] N V L Brokaw ldquoGap-phase regeneration of three pioneer treespecies in a tropical forestrdquo Journal of Ecology vol 75 no 1 pp9ndash19 1987

[58] S Itow and D Mueller-Dombois ldquoPopulation structure stand-level dieback and recovery of Scalesia pedunculata forest in theGalapagos Islandsrdquo Ecological Research vol 3 no 3 pp 333ndash339 1988

[59] T CWhitmore ldquoA review of some aspects of tropical rainforestseedling ecology with suggestions for further enquiryrdquo inEcology of Tropical Forest Tree Seedlings M D Swaine Ed pp3ndash39 UNESCOParthenon Paris France 1996

Submit your manuscripts athttpwwwhindawicom

Forestry ResearchInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Environmental and Public Health

Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

EcosystemsJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

MeteorologyAdvances in

EcologyInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Marine BiologyJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom

Applied ampEnvironmentalSoil Science

Volume 2014

Advances in

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Environmental Chemistry

Atmospheric SciencesInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Waste ManagementJournal of

Hindawi Publishing Corporation httpwwwhindawicom Volume 2014

International Journal of

Geophysics

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Geological ResearchJournal of

EarthquakesJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

BiodiversityInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

ScientificaHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

OceanographyInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Journal of Computational Environmental SciencesHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

ClimatologyJournal of

Page 14: Research Article Species Diversity and Tree Regeneration ...downloads.hindawi.com/archive/2013/890862.pdf · Species Diversity and Tree Regeneration Patterns in Tropical Forests of

14 ISRN Ecology

[46] ldquoWeblink 2007rdquo httpwwwbiodiversityhotspotsorgxphot-spotshotspots by region

[47] D Mueller-Dombois and H Ellenberg Aims and Methods ofPlant Ecology John Wiley amp Sons New York NY USA 1974

[48] K K N Nair and R Jayakumar ldquoPhytogeography endemismand affinities of the flora of NewAmarambalamReserve Forestsin theWesternGhats of Indiardquo Indian Journal of Forestry vol 31pp 85ndash94 2008

[49] A E Magurran Ecological Diversity and Its MeasurementCroom Helm Ltd London UK 1988

[50] C Raunkiaer The Life Forms of Plants and Statistical PlantGeography Clarendon Press Oxford UK 1934

[51] B Rice andMWestoby ldquoPlant species richness at the 01 hectarescale in Australian vegetation compared to other continentsrdquoVegetatio vol 52 no 3 pp 129ndash140 1983

[52] SM Scheiner ldquoSix types of species-area curvesrdquoGlobal Ecologyand Biogeography vol 12 no 6 pp 441ndash447 2003

[53] H G Jones Plants and Microclimate Cambridge UniversityPress Cambridge UK 1983

[54] N C Nair The Southern Western Ghats A Biodiversity Con-servation Plan Indian National Trust for Arts and CulturalHeritage New Delhi India 1991

[55] AHGentry ldquoChanges in plant community diversity and floris-tic composition on environmental and geographical gradientrdquoAnnals of the Missouri Botanical Garden vol 75 no 1 pp 1ndash341988

[56] T CWhitmore Tropical Rain Forests of the Far East ClarendonPress Oxford UK 1984

[57] N V L Brokaw ldquoGap-phase regeneration of three pioneer treespecies in a tropical forestrdquo Journal of Ecology vol 75 no 1 pp9ndash19 1987

[58] S Itow and D Mueller-Dombois ldquoPopulation structure stand-level dieback and recovery of Scalesia pedunculata forest in theGalapagos Islandsrdquo Ecological Research vol 3 no 3 pp 333ndash339 1988

[59] T CWhitmore ldquoA review of some aspects of tropical rainforestseedling ecology with suggestions for further enquiryrdquo inEcology of Tropical Forest Tree Seedlings M D Swaine Ed pp3ndash39 UNESCOParthenon Paris France 1996

Submit your manuscripts athttpwwwhindawicom

Forestry ResearchInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Environmental and Public Health

Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

EcosystemsJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

MeteorologyAdvances in

EcologyInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Marine BiologyJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom

Applied ampEnvironmentalSoil Science

Volume 2014

Advances in

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Environmental Chemistry

Atmospheric SciencesInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Waste ManagementJournal of

Hindawi Publishing Corporation httpwwwhindawicom Volume 2014

International Journal of

Geophysics

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Geological ResearchJournal of

EarthquakesJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

BiodiversityInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

ScientificaHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

OceanographyInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Journal of Computational Environmental SciencesHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

ClimatologyJournal of

Page 15: Research Article Species Diversity and Tree Regeneration ...downloads.hindawi.com/archive/2013/890862.pdf · Species Diversity and Tree Regeneration Patterns in Tropical Forests of

Submit your manuscripts athttpwwwhindawicom

Forestry ResearchInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Environmental and Public Health

Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

EcosystemsJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

MeteorologyAdvances in

EcologyInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Marine BiologyJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom

Applied ampEnvironmentalSoil Science

Volume 2014

Advances in

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Environmental Chemistry

Atmospheric SciencesInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Waste ManagementJournal of

Hindawi Publishing Corporation httpwwwhindawicom Volume 2014

International Journal of

Geophysics

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Geological ResearchJournal of

EarthquakesJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

BiodiversityInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

ScientificaHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

OceanographyInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Journal of Computational Environmental SciencesHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

ClimatologyJournal of