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Hindawi Publishing CorporationJournal of Marine BiologyVolume 2013 Article ID 684739 16 pageshttpdxdoiorg1011552013684739

Research ArticleTidal Influence on Nutrients Status and PhytoplanktonPopulation of Okpoka Creek Upper Bonny Estuary Nigeria

O A Davies1 and O A Ugwumba2

1 Department of Fisheries and Aquatic Environment Rivers State University of Science and TechnologyP M B 5080 Port Harcourt Nigeria

2Hydrobiology and Fisheries Unit Department of Zoology University of Ibadan Ibadan 900001 Nigeria

Correspondence should be addressed to O A Davies daviesonomeyahoocom

Received 26 April 2013 Revised 24 July 2013 Accepted 25 July 2013

Academic Editor E A Pakhomov

Copyright copy 2013 O A Davies and O A Ugwumba 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

Okpoka Creek of the Upper Bonny Estuary in the Niger Delta is a tidal creek receiving organic anthropogenic effluents fromits environs The study investigated the influence of tides (low and high) on the species composition diversity abundance anddistribution of phytoplanktonThe surface water and phytoplankton samples were collected monthly fromMay 2004 to April 2006at both tides from ten stations according to standard methods Phytoplankton was identified microscopically Species diversitywas calculated using standard indices Data analyses were done using analysis of variance Duncan multiple range and descriptivestatistics Phosphate and ammonia exceeded international acceptable levels of 010mgL for natural water bodies indicating highnutrient status organicmatter and potential pollutants A total of 158 species of phytoplankton were identified Diatoms dominatedthe phytoplankton (629) Diversity indices of diatoms were 15 plusmn 003 (Margalef) and 08 plusmn 001 (Shannon) Pollution-indicatorspecies such as Navicula microcephala Nitzschia sigma Synedra ulna (diatoms) Cladophora glomerata (green alga) Euglena acus(euglenoid) Anabeana spiroides (blue-green alga) and Ceratium furca (dinoflagellate) were recorded at either only low high orboth tides Concerted environmental surveillance on Upper Bonny Estuary is advocated to reduce the inflow of pollutants fromthe Bonny Estuary into this Creek caused by tidal influence

1 Introduction

Estuaries are unique aquatic environments that have anadditional source of buoyancy input derived from riverinefreshwater inflow and an additional source of mechanicalenergy input from the tides (tidal stirring) Estuarine ecosys-tems are very favourable for algae and animal life Theyplay an important ecological role because they are naturalhabitants of water They are widely used as an indicatorof water pollution [1] The Bonny Estuary is one of theseveral estuaries in the Niger Delta swamps through whichthe Lower Niger and Benue Rivers flow into the ocean Theestuary is richly endowed with abundant aquatic resources(creeks distributaries flood plains and mangrove swampswith finshell fish resources etc) The estuary its creeksand tributaries consist of rich collection of flora and faunaconstituting a unique tropical biodiversity The vegetation of

Bonny Estuary is dominated by the redmangroveRhizophoraracemosa andRmangle [2]Themangrove provides nurseriesand feeding grounds for commercially important species offinfish and shellfish Despite its good environment for aquaticlife forms the area is prone to pollution resulting fromindustries located along the shore of Bonny Estuarywhich areconcentrated in this zone and they discharge their effluentsdirectly into the estuaryThe flushing action of the tidal flowscontributes to moving these pollutants down into the coastalzones Okpoka Creek is a tidal tributary of the Upper BonnyEstuary Tidal influence on this creek is twenty-four hours atinterval of six hours of low and high tides alternatively

Tides play a major role in the functioning of manycoastal systems They are responsible for obvious midterm(spring-neap cycles) and short-term (low-high water cycles)variations in the abiotic and biotic characteristics of these

2 Journal of Marine Biology

systems [3] Tidal flushing is one of the main bottom-up fac-tors controlling phytoplankton biomass in estuaries besidesnutrients [4]Quite a number ofworks had been conducted toevaluate tidal control of plants and animals communities andprocesses in different systems These include tide-inducedphytoplankton and microphytobenthos exchanges [5] tidalinfluence on bacteria microphytoplankton and microzoo-plankton abundance [6] tidal stirring and phytoplanktonbloom dynamic in an estuary [7] tidal influence on zonationand occurrence of resident and temporary zooplankton inMundaka Estuary Bay of Biscay [3] and effects of tidalshallowing and deepening on phytoplankton productiondynamics a modeling study [8] and dancing with the tidesfluctuations of coastal phytoplankton orchestrated by differ-ent oscillatory modes of the tidal cycle [9]

Phytoplankton populations are highly dynamic and inmany environments they experience episodes of rapid bio-mass increase (blooms) either as recurrent seasonal events oras higher frequency phenomena [7] According to Badsi [1]Rajesh et al [10] Ananthan et al [11] Tiwari and Chauhan[12] Tas andGonulol [13] and Saravanakumar et al [14] phy-toplanktonic organism is one of the initial biological compo-nents from which the energy is transferred to higher organ-isms through food chain The density and the diversity ofphytoplankton are biological indicators for evaluating waterquality and the degree of eutrophication [1 15 16]

There are many human activities going on around andin the creek such as slaughtering of animal transportation(boating navigation) fishing and waste disposal Howeverthere has been no information on the influence of tide on thenutrients status and phytoplankton community of OkpokaCreek a tidal tributary of Upper Bonny Estuary In order tobridge the existing gap in knowledge of the biotic and abioticfeatures of this estuary there is therefore the need to provideuseful information on the tidal variations of water nutrientsand phytoplankton population of this Creek Based on thisthe study thus evaluated the influence of low and high tideson nutrients abundance species composition diversity anddistribution of the phytoplankton of Okpoka Creek

2 Materials and Methods

21 Study Area Okpoka Creek is located between longi-tudes 7∘0010158401015840E and 7∘1510158401015840N and latitudes 4∘2810158401015840E and 4∘4010158401015840N(Figure 1) The vegetation is dominated by nypa palm (Nypafrutican) and mangroves red mangrove (Rhizophora race-mosa) and white mangrove (Avicennia nitida) It passesthrough many communities namely Oginigba Woji andAzubiae Many manrsquos activities going on within and aroundthis creek include dredging fishing boating navigationwashing disposal of excreta bathing and swimming tomention but a few This aquatic body receives effluentdischarges from the many industries (Snig Far East paintsRIVOC General-agro Michelin tyres Coca Cola Hallibur-ton Schlumberger Acorn etc) andmain abattoir house sitedclose to itThe stretch of the coastal front of the creek has veryhigh population density without wastemanagement facilities

All the industries in the Trans-Amadi Industrial Layout andthe riverine dwellers discharge their wastes directly to thiscreek

22 Sampling Stations A total of ten stations were chosen atleast 500 metres apart along the main creek course Thesestations were Station 1 (Oginigba) Station 2 (Trans-Amadiby Schlumberger) Station 3 (bymain abattoir house) Station4 (Azubiae) Station 5 (Woji) Station 6 (Okujagu) Station 7(Okuru-ama) Station 8 (Ojimba) Station 9 (Oba-ama) andStation 10 (Kalio-ama) There are many industries sited closeto the river shore discharging effluents into the creek Thedominant vegetation is nypa palm (Nypa frutican) followedby drying up red mangrove Patches of water hyacinth wereseen during the rainy season Manual dredging of sand isconstantly going on

23 Physicochemical Parameters of the Water The followingparameters weremeasured in situ and in laboratory followingstandard methods [17] One-litre clean containers were usedto collect water samples for physicochemical parametersat each station All the kegs containers were kept in ice-chest box for laboratory analyses Nitrate was determinedby the Brucine method [17] Spectrophotometer (spectronic21D) was used to measure the nitrate at 410 nm wavelengthSulphate determination was carried out by turbidimetricprocedure [17] This involved the use of spectrophotometer(Spectronic 21D) The concentration of sulphate (mgL) wasmeasured thus

Sulphate =mgSO

4

times 1000

Volume of sample used (mL) (1)

Phosphate-in-water levels were determined by standardtest [17] It involved the use of spectrophotometer (Spectronic21D) The concentration of phosphate (mgL) was measuredthus

Phosphate =mgPO

4

times 1000


Ammonia concentrations in water samples were deter-mined by the indophenol or phenate (phenol-hypochlorite)method It was spectrophotometrically measured at 630 nmwavelength with spectronic 21D [17] The concentrationof total ammonia in the samples was computed from theequation

1198621

1198622

=1198601

1198602

(3)

where 1198601= the absorbance of the total ammonia-nitrogen

standard 1198602= the absorbance of the sample and 119862

1= the

concentration of the total ammonia-nitrogen standard 1198622=

the concentration of total ammonia nitrogen in the sample(Boyd [18])

Journal of Marine Biology 3

LGA boundaryLocal government headquartersTown

VillageRivers and creekSample points

N N

N N

N N

NN NN

Figure 1 Study area map

24 Collection of Phytoplankton Samples and Analyses Sam-plings were done at low and high tides Surface water sampleswere collected using one one-litre wide mouth plasticcontainer [17] at each station The sample in the containerwas fixed with 10 formalin for phytoplankton identificationand enumeration (standing crop estimation) In the labora-tory samples were allowed to stand for a minimum of 24hours before decanting the supernatantThe supernatant wasremoved carefully until a 50mL concentrated sample wasproperly shaken and 1mL of sub sample was collected fromit and transferred into a Sedgwick-Rafter counting chamberusing a stampel pipette Identification and enumeration(standing crop estimation) was carried out under a binocularcompound microscope with magnification 40 times 400 Threereplicates of the subsamples were analysed For each sampleeach solitary cell or group of cells were counted as oneunit except for the diatoms which were counted in a cell bycell base Results were expressed in a number of organismsper mL of sample The Sedgwick-Rafter counting chambercontains exactly 1mL (50mm long times 20mm wide times 1mmdeep) and has a surface area of 1000mm2 The exact areaviewed within the ocular micrometer grid is also known

The following formula was used for the calculation of plank-ton density

Density of plankton (Number of plankters per mL)

= (T) 1000ANtimesVolume of concentrate mLVolume of sample (mL)

(4)

where119879 = total number of plankters counted119860 = area of gridin mm2119873 = number of grids employed and 1000 = area ofcounting chamber in mm2 (Boyd [18])

Identification and characteristics of planktonic specieswere made by the descriptive keys by J G Needham andP R Needham [19] G E Newell and R C Newell [20]Patrick and Reimer [21] Han [22] Durans and Leveque [23]and Prescott [24] and Kadiri [25] amongst others Margalefspecies diversity index was estimated by this formula

119867 =119878 minus 1

In119873 (5)

where 119878 = the number of species (or other taxonomic group)and119873 = total number of phytoplankters (Boyd [18])


Table 1 Important values assigned to ith species abundance

Range Importance value1ndash10 111ndash20 221ndash30 331ndash40 441ndash50 551ndash60 661ndash70 771ndash80 881ndash90 991ndash100 10100 and above 11

Index of dominance (119862) was determined by the formula

119862 = sum(119899119894

119873)

2

(6)

where 119899119894 = importance value for each species (numberof individual biomass production etc) and 119873 = total ofimportance values

Importance values (Table 1) were assigned to the phyto-plankton species based on the contribution of each species tototal net primary production [26] and also to pollution

Index of similarity (119878) in phytoplankton species diversitybetween the low and high tides was determined by index ofsimilarity (119878) between 2 adjacent samples [26] as follows

119878 =2119862

119860 + 119861 (7)

where 119860 = number of species in sample 119860 119861 = number ofspecies in sample 119861 and 119862 = number of species common inboth samples

Index of dissimilarity = 119868 minus 119878 (8)

Other indices of species diversity calculated are as fol-lows

(1) Shannon index of general diversity (119867) was calculatedthus

119867 = sum(119899119894

119873) log(119899119894119873) or minussum119875119894 log119875119894 (9)

where 119899119894 = importance value for each species 119873 =total of importance values and 119875119894 = importanceprobability for each species = 119899119894119873

(2) Evenness index (119890) is

119890 =119867

log119890

119878 (10)

where119867 = Shannon index and 119878 = number of species

3 Data Analyses

SAS [27] was used to analyse data for analysis of variance(ANOVA) Duncan multiple range (DMR) and descriptivestatistics

Table 2 Variations of water nutrients in relation to tide in OkpokaCreek

Tide Ammonia(mgL)

Nitrate(mgL)

Phosphate(mgL) Sulphate (mgL)

Low 017 plusmn 001a 068 plusmn 002a 077 plusmn 005a 58611 plusmn 3642a

High 019 plusmn 002a 048 plusmn 004b 029 plusmn 007b 45909 plusmn 3389a

Means with the same letter in the same column are not significantly different(119875 gt 005)

4 Results and Discussion

41 Nutrients of Surface Water from Okpoka Creek Gener-ally phytoplankton growth is limited by inorganic nutrients(phosphorous nitrogen silicon iron etc) Nutrients statusaffects the composition of phytoplankton as its composi-tion changes with the nutrient fluxes because individualtaxa have different requirements High tide ammonia level(019 plusmn 002mgL) was not significantly (119875 gt 005 DMR)higher than low tide ammonia (017 plusmn 001mgL) with amean of 017 plusmn 001mgL (Table 2) This possibly indicatedanthropogenic inputs from the numerous industries andriverine dwellers located along the water course of OkpokaCreek at high tide Higher concentration of ammonia athigh tide favoured the observed diatoms green algae blue-green algae dinoflagellates and xanthophytes especially thedominant diatoms at high tide The lower concentrationof ammonia at low tide favoured the other phytoplanktongroups (chrysophytes and euglenoids) Ammonia is oneof the nutrients required by phytoplankton for primaryproductivity Others are nitrate phosphorus and sulphate[28] Furthermore ammonia is a source of nitrogen andcontributes to the fertility of water since nitrogen is anessential plant nutrient It is also one of the most importantpollutants in aquatic environment because of its relative hightoxic nature and its ubiquity in surface water systems [29]Ammonia enters natural water systems from several sourcesincluding industrial wastes sewage effluents coal gasificationand liquefaction conversion process plants and agriculturaldischarge including feedlot runoff The study ammoniaexceeded the concentration of less than 01mgL found innatural waters [30] This possibly indicates anthropogenicand domestic inputs The mean ammonia concentration isalso higher than the level of 002mgL unionized ammonia(NH3) required for the protection of aquatic life [31] How-

ever the recorded range of ammonia in this creek is withinthe range of 0093mgL to 265mgL reported by ChindahandNduaguibe [32] andObunwo et al [33] in theNigerDelta

Nitrate nitrogen and ammonia nitrogen determine com-munity productive levels The lower concentrations of sul-phate nitrate and phosphate at high tide might signified lowprimary productivity Tides cause a pattern of stabilization-destabilization in circulation that results in the highest ratesof primary production in many estuarine coastal oceanicor frontal environments [34] Destabilization period occursduring flood or ebb tides or during fast current movementThis results in a replenishment of nutrients to the photiczone from more nutrient-rich underlying waters During


and following the destabilization period photosynthesis isdecreased by a shortage of light due to increased turbidity andmixing of the phytoplankton to deeper waters Circulationpatterns are vital in establishing the balance between lightlevels and nutrient availability necessary to maintain highprimary productivity rates in marine systems

The higher concentration of nitrate phosphate and sul-phate at low tide might be attributed to the higher abundanceof chrysophytes and euglenoids at low tide These nutrientsindicated high primary productivity and that these phyto-plankters are primary producers At low tide stabilizationin circulation leads to increased rate of photosynthesisStabilization period occurs during slack tides or slow currentsand results in increased rates of photosynthesis and nutrientuptake [34] Nutrients availability especially phosphorusstructures the algae community [35] In addition primaryproductivity (phytoplankton productivity) is expected to behigh at low tide (low water) as turbidity is low and solar andlight penetrations are high

Nitrate concentration (068 plusmn 002mgL) was high atlow tide and low (048 plusmn 004mgL) at high tide with amean of 064 plusmn 002mgL The highest nitrate recordedat low tide might be indicative of high human excrementand industrial discharges Stabilization period occurs duringslack tides or slow currents and results in increased rates ofnutrient uptake [34] This also might be the possible reasonfor this observation Tidal effect was highly significant (119875 lt0001 DMR) The observed mean nitrate is below 100mgLexpected to be found in natural surface water Nitrogen ismost often limiting inmarine systems [36]The reasons beingthat molybdenum phosphorus or energy constraint can belimiting to nitrogen fixers which makes for lower nitrogenfixation [37] The range of nitrate recorded in this studywas below the statutory limit of 25ndash50mgL given by theEuropean Economic Community (EEC) [38] and 20mgLUnited State Environment Protection Agency (USEPA) [39]Low tide phosphate level (077 plusmn 005mgL) was higher thanthat of high tide (029 plusmn 007mgL) with a mean of 070 plusmn005mgLThe effect of tide was significant (119875 lt 005 DMR)

The higher phosphate at low tide could be due to highdecomposition of organic matter and stabilization periodTide influence on the sulphate concentrations was not sig-nificant (119875 gt 005) The recorded phosphate concentra-tions in this study were higher than the acceptable limitof 010mgL in flowing waters recommended by USEPA[39] and United States Geological Survey (USGS) [40] Thisobservation agrees with that of 043 to 352mgL of Chindahand Nduaguibe [32]

Low tide mean sulphate level was 58611 plusmn 3642mgL(higher) and high tide level was 45909 plusmn 3389mgL (lower)with a mean value of 56005 plusmn 2887mgL This couldbe attributed to the higher biological oxygen demand andstabilization period at low tide than at high tide Oxidationof the organic materials and burning of fossil fuel used upoxygen thereby exerting higher biological oxygen demandin the creek The high sulphate level observed in this studyis characteristic of brackish water Ebere [41] reported thatmarine waters are known to contain relatively high concen-trations of sulphate McNeely et al [30] observed 2650mgL

7166

8

1672

97

457

26

382

31

964

6

286

74 1330

48

0

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8000

Den

sity

(No

mL)

Baci

llario

phyc

eae

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roph

ycea

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soph

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ophy

ceae

Eugl

enop

hyce

ae

Pyrr

ophy

ceae

Xant

hoph

ycea

e

Phytoplankton class

Figure 2 Overall mean value of phytoplankton density in OkpokaCreek

sulphate in seawater The recorded sulphate is below thesulphate values in seawater that is within the acceptablelevels

42 Phytoplankton Community of Okpoka Creek Phytoplan-kton are free-floating and mostly microscopic plants andthey cannot swim instead they are transported by tides andcurrents A total of forty-nine thousand four hundred andseventy nine (48479) phytoplankton consisting of seven (7)families seventy-nine (79 genera) and one hundred andfifty-eight (158) species were identified These values weremore than the values reported for studies on other waters ofthe Niger Delta This could be due to environmental influ-ence The algae were Bacillariophyceae (diatoms) 80 speciesChlorophyceae (green algae) 44 species Cyanophyceae(blue-green algae) 21 species Euglenophyceae (euglenin)6 species Pyrrophyceae (dinoflagellates) 4 species Xan-thophyceae (xanthophytes) 2 species and Chrysophyceae(chrysophytes) 1 species The observed abundance of phy-toplankton differs with that of Edoghotu [42] for OkpokaCreek though it agrees with that study in terms of diatomsbeing the most abundant phytoplankton Other studies inthe Niger Delta of Nigeria are those of Chindah andKeremah [43] Chindah and Braide [44 45] on the BonnyEstuary Diatom dominance in this creek corresponded withthe study of Badsi et al [1] on Massa Estuary Diatomsrecorded the highest density (Figure 2) and this indicatedhigh productivity ofOkpokaCreek accordingwith Badsi et al[1] Also Moser et al [46] stated that diatoms are sensitiveto a wide range of limnological and environmental variablesand that their community structure may quickly respondto changing physical chemical and biological conditionsin the environment This might be the possible reason forthe dominance of diatoms in Okpoka Creek In additionreasons for the varied tidal abundance distribution species


Low tide High tide

BacillariophyceaeChlorophyceaeChrysophyceaeCyanophyceae

EuglenophyceaePyrrophyceaeXanthophyceae

0

1000

2000

3000

4000

5000

6000

7000

8000

9000

Den

sity

(No

ml)

Phyto

plank

ton c

lass

BacillariophyceaeChlorophyceae

ChrysophyceaeCyanophyceae

EuglenophyceaePyrrophyceae

Xanthophyceae

Figure 3 Variation of phytoplankton density Variations of phyto-plankton parameters in relation to tide in Okpoka Creek

composition and diversity of diatoms could be ascribed totheir resilient ability to withstand organic pollution Fur-thermore dominance of diatoms in terms of abundance andspecies composition indicates pollution [47] This shows thatdiatoms are resilient to the increased anthropogenic inputsand high turbidity at high tide The recorded abundance ofthe other phytoplankton classes explains this resilient abilityof diatoms Nevertheless some algae inhibit the growth ofothers for example Pyrmnesium parvum suppresses otheralgae by production of allelopathic chemical [48] Passy et al[49] reported that diatoms distribution is associated with adownstream increase in nutrient level and organic pollution

Chrysophytes and euglenoid flagellates recorded higherdensity at low tide (49531 plusmn 7933 nomL and 10574 plusmn1955 nomL) than at high tide (12425 plusmn 3399 nomL and6863 plusmn 1778 nomL) (Figure 3) This could possibly beexplained by the stabilization in circulationThe stabilizationin circulation favoured these algae The other observed algaerecorded higher densities at high tide than at low tide Tidalcycle is a major determinant of phytoplankton fluctuationsat several different time scales [9] A pattern of stabilization-destabilization in circulation results in the highest rates ofprimary production in many estuarine coastal oceanic orfrontal environments [34] Stabilization period occurs duringslack tides or slow currents and results in increased ratesof photosynthesis and nutrient uptake On the other handdestabilization period is experienced during flood or ebbtides or during fast current movement results in a replenish-ment of nutrients to the photic zone frommore nutrient-richunderlying waters During and following the destabilizationperiod photosynthesis is decreased by a shortage of light due

0

02

04

06

08

1

12

14

16

Mar

gale

f ind

ex

Baci

llario

phyc

eae

Chlo

roph

ycea

e

Chry

soph

ycea

e

Cyan

ophy

ceae

Eugl

enop

hyce

ae

Pyrr

ophy

ceae

Xant

hoph

ycea

e

Phytoplankton class

Low tideHigh tide

Figure 4 Variation of phytoplankton Margalef index Variations ofphytoplankton parameters in relation to tide in Okpoka Creek

to increased turbidity and mixing of the phytoplankton todeeper waters [34] Therefore circulation patterns are vitalin establishing the balance between light levels and nutrientavailability necessary to maintain high primary productivityrates inmarine systemsThehigher phytoplankton biomass atlow tide than at high tide was also reported by Okpuruka [50]of Elechi Creek in the Niger Delta Okpuruka [50] reportedthat Elechi Creek of the Upper Bonny Estuary in the NigerDelta had higher phytoplankton diversity during spring tidesthan neap tides

43 Bacillariophyceae (Diatoms) Diatoms density rangedfrom 690892 plusmn 39437 nomL (low tide) to 814029 plusmn72963 nomL (high tide) with a mean value of 716680 plusmn34773 nomL which was 6291 total abundance of phy-toplankton (Figures 2 and 3) High tide phytoplanktonparameters [density (814029 plusmn 72963 nomL) Margalef(153 plusmn 005) Shannon (084 plusmn 002) Evenness (042 plusmn 001)]were higher except Dominance (015 plusmn 001) than at lowtide [density (690892 plusmn 39437 nomL) Margalef (144 plusmn003) Shannon (077 plusmn 001) and Evenness (040 plusmn 001)and Dominance (018 plusmn 001)] (Figures 2 4 5 6 and 7)Tidal effects were significant on all phytoplankton parametersexcept Margalef and Dominance indices (119875 lt 001 DMR)

The presence of diatoms at both tides indicated thatspecies are euryhaline High values of these parametersexcept Dominance index signified high diversity of diatomsat high tide This observation could be attributed to tidal


0

01

02

03

04

05

06

07

08

09

Shan

non

inde

x

Baci

llario

phyc

eae

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roph

ycea

e

Chry

soph

ycea

e

Cyan

ophy

ceae

Eugl

enop

hyce

ae

Pyrr

ophy

ceae

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hoph

ycea

e

Phytoplankton class

Low tideHigh tide

Figure 5 Variation of phytoplankton Shannon index Variations ofphytoplankton parameters in relation to tide in Okpoka Creek

influence At high tide there is inflow of water from thesea into Okpoka Creek via the Upper Bonny Estuary thatbrings in phytoplanktonic organisms and other aquaticlife Phytoplankton are passively drifted microscopic plantsthus some marine diatom species might moved into thiscreek Tidal flushing is one of the main bottom-up fac-tors controlling phytoplankton biomass in estuaries besidesnutrients [4] According to Villate [3] tides are responsiblefor obvious midterm (spring-neap cycles) and short-term(low-high water cycles) variations in the abiotic and bioticcharacteristics of estuaries The recorded higher dominanceindex at low tide might indicate that the observed diatomspecies were true species (permanent residents) of this creekThe Shannon index value below 3 up to 3 at both tides showeda low specific structure of this group Based on principlea low diversity is a feature of young settlements of specieswhile a high diversity indicates mature settlements the lowdiversity index shows aweak internal structure of populations[1] The lower abundance and species diversity of diatoms atlow tide could be linked with the cycle of advection settlingand resuspension that follow the suspended particles duringthe ebb slack and flood tidal stages This cycle facilitatesthe retention of passive diatoms by physical trapping inthe Okpoka Creek In this creek the pattern of abundanceand species diversity of diatoms match the tidal cyclessuggesting that diatoms are displaced along the creekwithin adeterminate mass of waterThis means that physical trapping

0

005

01

015

02

025

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035

04

045

Even

ness

inde

x

Baci

llario

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roph

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e

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soph

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ophy

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ophy

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hoph

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e

Phytoplankton classLow tideHigh tide

Figure 6 Variation of phytoplankton evenness index Variations ofphytoplankton parameters in relation to tide in Okpoka Creek

and high water residence times serve to trap passively sinkingparticles such as diatoms without migrating behaviours intheir optimum estuarine environments [4]

There were 4 dominant genera and 10 prominent diatomsspecies out of the 80 observed species (Table 3) The specieswereMelosira undulata (2603 plusmn 1605) Cyclotella opercu-lata (1724 plusmn 163) M pusilla (1766 plusmn 096) Nitzschiasigma (1515 plusmn 164)M distans (1216 plusmn 413)N bilobata(1139 plusmn 195)M varians (1254 plusmn 073) Navicula bacil-lum (1137 plusmn 118) Cyclotella comta (1089 plusmn 132) andNitzschia filiforms (1132plusmn085) Tide had varied significanteffects on these 10 dominant species (119875 lt 005 DMR)Percentage abundances of C comta Nitzschia bilobata Nsigma andNavicula bacillum were significantly higher at lowtide than at high tide except N sigma (119875 lt 005) whilethe opposite was observed for C operculataM varians andM distans Percentage abundances of C operculata and Mdistanswere not significantly different (119875 gt 005)N filiformsM undulate andM pusilla were absent at low tide NaviculagracilisN cuspidataN placentulaNmicrocephalaN bacil-lumN amphibolaNitzschia sigmaN bilobataN lanceolataN paradoxa filiforms N longissima Cymbella cuspidataC lata Synedra ulna Cyclotella meneghiniana Tabellariafenestrate Cocconeis placentula and Pinnularia major areorganic pollution indicator species and were present at bothtides [51ndash56] These species signified that Okpoka Creek isunder stress or suggested organic pollution at both tides fromanthropogenic inputs from the surrounding industries andwaterfront dwellers Also the presence of these species might


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e


Figure 7 Variation of phytoplankton dominance index Variationsof phytoplankton parameters in relation to tide in Okpoka Creek

further highlight inefficient disposal of domestic wastes inthis creek Nitzschia lanceolata N filiforms N longissima Nspp Navicula amphibola and N spp were present only athigh tide while Tabellaria fenestrate Cymbella cuspidata Pin-nulariamajorN paradoxaNavicula gracilisN cuspidataNplacentula and N microcephala were significantly abundantat high tide Cyclotella meneghiniana was not significantlyabundant at both tides but higher at high tide This showedthat these species exhibit migratory behaviour which is aidedby passive transport Cocconeis placentulawas present only atlow tide while Synedra ulna Nitzschia bilobata and Naviculabacillum were significantly abundant at low tide Nitzschiasigma was insignificantly abundant at both tides but higherat low tide Advection cycle settling and resuspension thatfollow the suspended particles during the ebb slack andflood tidal stages may explain this observationThese speciescould be autochthonous phytoplankton so they were able toremain and possibly grew at a very high rate at low tideAutochthonous phytoplankton population has the ability tomaintain itself within an estuarine segment and is determinedmainly by its rate of growth relative to the proportion of popu-lation biomass lost through flushing from the segment duringeach tidal cycle [4] Phytoplankton organisms may also usethe capacity to grow at very high rates as a physiologicalresponse in order to compensate for advective losses duringthe ebb tide Diatoms have the capacity for rapid cell divisionwith growth rates (up to 59 dayminus1) The flushing actionof the tidal flows contributed to movement of pollutants

(discharged into estuary by industries concentrated along it)down into the Okpoka Creek Tide had significant effect onsimilarity index (119875 lt 005 DMR) higher at low tide (7058 plusmn220) than at high tide (5935 plusmn 410) This showed thatdiatoms were similarly distributed at low tide (Table 4)

44 Chlorophyceae (Green Algae) Green algae densityranged between 165508 plusmn 12662 nomL (low tide) and172959 plusmn 2046 nomL (high tide) with a mean of 167297 plusmn10789 nomL which was 1468 total phytoplankton abun-dance Tide had significant impact on parameters except den-sity and Dominance index (119875 lt 005) The insignificant tidaldifferences in the density and dominance species indexmightbe that the passive drifting of green algae from the sea intotheOkpoka Creek via theUpper Bonny Estuary was probablylow These further suggested that tide had little or no effecton green algae populations Also it might be that the greenalgae of the Upper Bonny Estuary are environment selectiveor low in abundance Diversity indices varied betweenlow and high tides as follows Margalef (052 plusmn 050 and067 plusmn 051) Shannon (030 plusmn 002 and 037 plusmn 003) Evenness(027 plusmn 001 and 033 plusmn 002) and Dominance (025 plusmn 001and 025 plusmn 002)

Nine genera and 10 species out of the 44 observedgreen algae species were abundant (Table 5) The specieswere as follows Coelochaeta nitellarum (7616 plusmn 1616)Netrium digitus (4419 plusmn 472) Draparnaldia sp (42392 plusmn192) Entransia dichloroplastes (2385plusmn1616)Crucigeniafenestrata (3639 plusmn 270) Bulbochaeta sp (2048 plusmn 1286)Gonatozygon aculeatum (2969 plusmn 323) Microspora villena(2235 plusmn 233) C rectangularis (2147 plusmn 283) andCoelastrum microsporum (2004 plusmn 914) Tidal effects onthese green algae were different (119875 lt 005) It was observedthat Coleochaete nitellarum E dichloroplastes GonatozygonaculeatumNetrium digitus and Bulbochaeta sp were presentonly at low tide while C fenestrata and Microspora villeanawere significantly present at both tides (119875 lt 005) buttheir abundances were higher at low tide This probablysignified that at high tide these dominant green algae speciesmight rarely drift into the creek thus the higher percentagedistributions at low tide The variation of abundant of Dra-parnaldia sp C rectangularis and Coelastrum microsporumwere significantly higher at high tide than low tide Thepresence of Cladophora glomerata (especially at low tide)and Scenedesmus species (only at low tide) confirms thepolluted nature of Okpoka Creek and agrees with Nwankwoand Akinsoji [51] that C glomerata is tolerant to organicpollution and weak salinity Weak salinity is expected at lowtide as there is no inflow of sea water into the Okpoka Creekvia the Bonny Estuary The mean species similarity index of4360 plusmn 292 and dissimilarity index of 5640 plusmn 290 wererecorded Green algae species were similarly distributed atboth tides

45 Cyanophyceae (Blue-Green Algae) Cyanophytes rangedfrom 36947 plusmn 3152 nomL (low tide) to 41818 plusmn 5331 nomL (high tide) with a mean of 38231 plusmn 2710 nomLand represented 336 of the phytoplankton population


Table 3 Variations of Bacillariophyceae species under tidal influence in Okpoka Creek

Sno Species Means plusmn SEM () Statistical difference (ANOVA)Overall Low tide High tide

1 Cyclotella comta 1089 plusmn 132 1126 plusmn 154a 891 plusmn 122b 119875 lt 005

2 C meneghiniana 934 plusmn 097 934 plusmn 114a 936 plusmn 194 a119875 gt 005

3 C striata 731 plusmn 124 596 plusmn 136b 865 plusmn 202 a119875 gt 005

4 C operculata 1724 plusmn 163 1703 plusmn 198a 1833 plusmn 000a 119875 gt 005

5 C 119904119901119890119888119894119890119904lowast 396 plusmn 032 396 plusmn 032 mdash6 Fragilaria intermedia 194 plusmn 054 185 plusmn 032a 212 plusmn 191a 119875 gt 005

7 F capucina 266 plusmn 159 266 plusmn 159 mdash8 F construens 039 plusmn 000 mdash 039 plusmn 0009 F 119904119901119890119888119894119890119904lowast 302 plusmn 000 mdash 302 plusmn 00010 Epithermia zebra 047 plusmn 000 047 plusmn 000 mdash11 Attheya zacharias 079 plusmn 000 mdash 079 plusmn 00012 Stauroneis acuta 321 plusmn 000 321 plusmn 000 mdash13 S parvula 271 plusmn 000 mdash 271 plusmn 00014 S 119904119901119890119888119894119890119904lowast 197 plusmn 000 mdash 436 plusmn 10315 Diatoma vulgare 435 plusmn 077 433 plusmn 121a 065 plusmn 036b 119875 lt 005

16 Rhizosolenia sp 065 plusmn 036 mdash 169 plusmn 03417 Tabellaria fenestrate 162 plusmn 026 134 plusmn 002b 1281 plusmn 184a 119875 lt 005

18 Synedria ulna 1208 plusmn 171 880 plusmn 464a 382 plusmn 000b 119875 lt 005

19 S acus 451 plusmn 069 519 plusmn 000b 833 plusmn 141a 119875 lt 005

20 S affinis 729 plusmn 155 212 plusmn 000 b 881 plusmn 127a 119875 lt 005

21 S 119904119901119890119888119894119890119904lowast 1026 plusmn 126 1414 plusmn 196a 990 plusmn 122b 119875 lt 005

22 Coscinodiscus lacustris 946 plusmn 100 781 plusmn 152 a 564 plusmn 155b 119875 lt 005

23 C radiate 639 plusmn 118 790 plusmn 171a 096 plusmn 000b 119875 lt 005

24 C excentricus 096 plusmn 000 mdash 741 plusmn 66125 C 119904119901119890119888119894119890119904lowast 741 plusmn 661 mdash 253 plusmn 06626 Amphora ovalis 268 plusmn 054 317 plusmn 086b 1548 plusmn 176a 119875 lt 005

27 Nitzschia sigma 1515 plusmn 164 1184 plusmn 446a 1016 plusmn 278a 119875 gt 005

28 N bilobata 1139 plusmn 195 1386 plusmn 155a 850 plusmn 245b 119875 lt 005

29 N lanceolata 850 plusmn 245 mdash 664 plusmn 07030 N paradoxa 683 plusmn 060 775 plusmn 000b 1133 plusmn 085a 119875 lt 005

31 N filiforms 1133 plusmn 085 mdash 1017 plusmn 00032 N longissima 1017 plusmn 000 mdash 708 plusmn 34733 N 119904119901119890119888119894119890119904lowast 708 plusmn 347 mdash 806 plusmn 16034 Navicula gracilis 715 plusmn 154 349 plusmn 000b 1129 plusmn 173a 119875 lt 005

35 N cuspidata 1074 plusmn 160 691 plusmn 000b 1021 plusmn 071a 119875 lt 005

36 N placentula 1009 plusmn 060 953 plusmn 107b 1241 plusmn 111a 119875 lt 005

37 N microcephala 1033 plusmn 172 721 plusmn 309b 1018 plusmn 211a 119875 lt 005

38 N bacillum 1137 plusmn 118 1255 plusmn 106a 037 plusmn 000b 119875 lt 005

39 N amphibola 037 plusmn 000 mdash 953 plusmn 29540 N 119904119901119890119888119894119890119904lowast 953 plusmn 295 mdash 1314 plusmn 07341 Melosira varians 1254 plusmn 073 1013 plusmn 207b 2603 plusmn 1605a 119875 gt 005

42 M undulate 2603 plusmn 1605 mdash 1766 plusmn 09643 M pusilla 1766 plusmn 096 mdash 1462 plusmn 57344 M distans 1216 plusmn 413 723 plusmn 000a 785 plusmn 025a 119875 gt 005

45 M listans 908 plusmn 099 1092 plusmn 201 mdash46 M granulate 160 plusmn 000 160 plusmn 000a 077 plusmn 000a 119875 gt 005


Table 3 Continued


47 M 119904119901119890119888119894119890119904lowast 077 plusmn 000 mdash 316 plusmn 00148 Cymbella cuspidata 234 plusmn 082 070 plusmn 000b 220 plusmn 000a 119875 lt 005

49 C lata 220 plusmn 000 mdash 359 plusmn 00150 Asterionella formosa 084 plusmn 000 084 plusmn 1000b 241 plusmn 000a 119875 lt 005

51 Surirella 119904119901119890119888119894119890119904lowast 241 plusmn 000 mdash 194 plusmn 00052 S tenera 125 plusmn 070 055 plusmn 000 099 plusmn 00053 S elegans 099 plusmn 000 mdash 466 plusmn 22554 S robusta 549 plusmn 208 1048 plusmn 000a 027 plusmn 000b 119875 lt 005

55 Cymatopleura 119904119901119890119888119894119890119904lowast 027 plusmn 000 mdash 116 plusmn 00056 Campylodiscus hibernicus 116 plusmn 000 mdash 230 plusmn 11857 Pinnularia viridis 203 plusmn 073 mdash 175 plusmn 03058 P horealis 290 plusmn 082 405 plusmn 139a 056 plusmn 021b 119875 lt 005

59 P major 087 plusmn 033 149 plusmn 000b 669 plusmn 110a 119875 lt 005

60 P 119904119901119890119888119894119890119904lowast 669 plusmn 110 mdash 700 plusmn 11261 Frustulia rhomboides 735 plusmn 096 840 plusmn 204a 708 plusmn 081a 119875 gt 005

62 Gyrosigma acuminatum 724 plusmn 075 776 plusmn 188b 1576 plusmn 000a 119875 lt 005

63 G 119904119901119890119888119894119890119904lowast 1576 plusmn 000 mdash 1146 plusmn 00064 G attenuatum 1146 plusmn 000 mdash 353 plusmn 00065 G paradoxa 353 plusmn 000 mdash 561 plusmn 10866 Stephanodiscus astraea 610 plusmn 107 998 plusmn 000 mdash67 S 119904119901119890119888119894119890119904lowast 170 plusmn 000 170 plusmn 000 mdash68 Cocconeis placentula 038 plusmn 000 038 plusmn 000 mdash69 Bacteriastrum 010 plusmn 000 010 plusmn 000 mdash70 Bacillaria 119904119901119890119888119894119890119904lowast 157 plusmn 000 152 plusmn 000 mdash71 Biddulphia 119904119901119890119888119894119890119904lowast 030 plusmn 000 030 plusmn 000 mdash72 Corethron hystrix 1082 plusmn 000 1082 plusmn 000 mdash73 Cylindrotheca 119904119901119890119888119894119890119904lowast 467 plusmn 000 467 plusmn 000 mdash74 C gracilis 267 plusmn 000 267 plusmn 000 mdash75 Diploneis 119904119901119890119888119894119890119904lowast 007 plusmn 000 007 plusmn 000 mdash76 Ditylum 119904119901119890119888119894119890119904lowast 010 plusmn 000 010 plusmn 000 mdash77 Hydrosera 119904119901119890119888119894119890119904lowast 100 plusmn 000 100 plusmn 000 mdash78 Skeletonema 119904119901119890119888119894119890119904lowast 084 plusmn 000 084 plusmn 000 mdash79 Thalassiothrix 119904119901119890119888119894119890119904lowast 013 plusmn 000 013 plusmn 000 mdash80 T longissimum 017 plusmn 000 017 plusmn 000 mdashMeans with the same letter in the same row are not significantly different (119875 gt 005)lowastMeans unidentified mdash absent

Table 4 Variations of phytoplankton similarity and dissimilarity indices in relation to tide in Okpoka Creek

Tide Bacillariophyceae Chlorophyceae Cyanophyceae Xantophyceae Pyrrophyceae Chrysophyceae EuglenophyceaeSimilarity index ()

Low 7058 plusmn 220a

4375 plusmn 340a1738 plusmn 344

a3868 plusmn 557

a1232 plusmn 485

b1724 plusmn 714

a982 plusmn 419

a

High 5935 plusmn 410b


a1340 plusmn 716

a4000 plusmn 2450

a0000 plusmn 000

a957 plusmn 650

a

Dissimilarity index ()Low 2942 plusmn 215

b5625 plusmn 339

a8262 plusmn 343

a6132 plusmn 562

a8768 plusmn 686

a8276 plusmn 714

a9018 plusmn 687

a

High 4065 plusmn 410a


a8660 plusmn 716

a6000 plusmn 2450

a10000 plusmn 000

a9043 plusmn 558

a

Means with the same letter in the same column are not significantly different (119875 gt 005)


Table 5 Variations of Chlorophyceae species under tidal influence in Okpoka Creek


1 Microspora villeana 2235 plusmn 233 2315 plusmn 289a 1918 plusmn 061b 119875 lt 005

2 Spirotaenia 119904119901119890119888119894119890119904lowast 1188 plusmn 412 1188 plusmn 412 mdash3 Coelochaeta nitellarum 7616 plusmn 1616 7616 plusmn 1616 mdash4 Mesotaenium 119904119901119890119888119894119890119904lowast 1608 plusmn 817 2655 plusmn 1346 a 559 plusmn 024 b

119875 lt 005

5 Entransia dichloroplastes 2385 plusmn 1616 2385 plusmn 1616 mdash6 Chactosphora 119904119901119890119888119894119890119904lowast 147 plusmn 000 147 plusmn 000 mdash7 Tetraedron tumidulum 753 plusmn 251 848 plusmn 304 a 376 plusmn 245 b

119875 lt 005

8 Tetmemorus 119904119901119890119888119894119890119904lowast 177 plusmn 000 mdash 177 plusmn 0009 Penium 119904119901119890119888119894119890119904lowast 207 plusmn 000 207 plusmn 000 mdash10 Crucigenia rectangularis 2147 plusmn 283 1813 plusmn 203b 2815 plusmn 681a 119875 lt 005

11 C fenestrate 3639 plusmn 270 3762 plusmn 273 a 2656 plusmn 000 b119875 lt 005

12 C puadrata 1365 plusmn 362 1266 plusmn 492 b 1661 plusmn 000 a119875 lt 005

13 Gonatozygon aculeatum 2969 plusmn 323 2969 plusmn 323 mdash14 G 119904119901119890119888119894119890119904lowast 1218 plusmn 639 1218 plusmn 639 mdash15 Staurastrum grande 590 plusmn 221 736 plusmn 288 a 299 plusmn 000 b

119875 lt 005

16 S natator 1429 plusmn 000 1429 plusmn 000a 618 plusmn 002 b119875 lt 005

17 Closterium dianae 618 plusmn 002 mdash 2159 plusmn 09218 C parvulum 1616 plusmn 249 1074 plusmn 292 a 721 plusmn 212 b

119875 lt 005

19 C gracile 781 plusmn 175 1019 plusmn 211 a 236 plusmn 000 b119875 lt 005

20 C kuetzingii 236 plusmn 000 mdash 181 plusmn 00021 C macilentus 181 plusmn 000 mdash 472 plusmn 00022 C strigosum 472 plusmn 000 mdash 501 plusmn 00123 Cosmarium 119904119901119890119888119894119890119904lowast 714 plusmn 000 714 plusmn 000b 2000 plusmn 000a 119875 lt 005

24 C granatum 1140 plusmn 860 280 plusmn 000b 1342 plusmn 000a 119875 lt 005

25 Cladophora glomerata 1594 plusmn 252 1845 plusmn 000 a 973 plusmn 555 b119875 lt 005

26 C elegans 1221 plusmn 298 1469 plusmn 271 b 6499 plusmn 3082 a119875 lt 005

27 Draparnaldia 119904119901119890119888119894119890119904lowast 4239 plusmn 2192 850 plusmn 647 b 2489 plusmn 1858 a119875 lt 005

28 Coelastrummicroporum 2004 plusmn 914 1580 plusmn 1095 b 1896 plusmn 396 a119875 lt 005

29 C recticulatum 1662 plusmn 328 882 plusmn 244 b 1333 plusmn 000 a119875 lt 005

30 Rhizodonium hookeri 1298 plusmn 036 1262 plusmn 000 a 101 plusmn 000 b119875 lt 005

31 Desmidium grevillii 152 plusmn 051 203 plusmn 000 b 1153 plusmn 229 a119875 lt 005

32 D aptogonum 862 plusmn 319 280 plusmn 000 b 509 plusmn 000 a119875 lt 005

33 Planktosphaeria gelatinosa 521 plusmn 012 533 plusmn 000 b 4371 plusmn 506 a119875 lt 005

34 Netrium digitus 4419 plusmn 472 172 plusmn 000 mdash35 Treubaria crassispina 172 plusmn 000 2048 plusmn 1286 mdash36 Bulbochaeta 119904119901119890119888119894119890119904lowast 2048 plusmn 1286 1290 plusmn 044 mdash37 Clostridium lunula 1290 plusmn 044 762 plusmn 000 mdash38 Docidium 119904119901119890119888119894119890119904lowast 762 plusmn 000 4444 plusmn 000 mdash39 Ankistrodesmus 119904119901119890119888119894119890119904lowast 4444 plusmn 000 741 plusmn 000 mdash40 Oedogonium 119904119901119890119888119894119890119904lowast 741 plusmn 000 3833 plusmn 000 mdash41 Scenedesmus 119904119901119890119888119894119890119904lowast 3833 plusmn 000 1482 plusmn 000 mdash42 Spirogyra 119904119901119890119888119894119890119904lowast 1482 plusmn 000 207 plusmn 000 mdash43 Cladophora 119904119901119890119888119894119890119904lowast 207 plusmn 000 1715 plusmn 286 mdash44 Netrium 119904119901119890119888119894119890119904lowast 1715 plusmn 286 1805 plusmn 305 mdashMeans with the same letter in the same row are not significantly different (119875 gt 005)lowastMeans unidentified mdash absent


0102030405060708090

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Cyanophyceae phytoplankton Species

Figure 8 Overall mean values of Cyanophyceae species in OkpokaCreek (1 =A sp 2 =A affinis 3 =A arnoldii 4 =A spiroides 5 =Aarnoldii 6 = S subsalsa 7 = S laxissima 8 = S major 9 = S princeps10 =M pulverea 11 =O princeps 12 =O lacustris 13 =O tenuis 14 =O sp 15 = R sp 16 = L hieronymussi 17 = L limnetica 18 = L major19 = R curvata 20 = P musicola and 21 = N sp)

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LowDry

Figure 9 Variation of Cyanophyceae species in relation to tide inOkpoka Creek (1 = A sp 2 = A affinis 3 = A arnoldii 4 = Aspiroides 5 =A arnoldii 6 = S subsalsa 7 = S laxissima 8 = Smajor9 = S princeps 10 = M pulverea 11 = O princeps 12 = O lacustris13 = O tenuis 14 = O sp 15 = R sp 16 = L hieronymussi 17 = Llimnetica 18 = L major 19 = R curvata 20 = P musicola and 21 =N sp)

The ANOVA for these phytoplankton parameters showedinsignificant difference (119875 gt 005) The insignificant higherdensity of blue-green algae at high tide might be traced toinflow of these plants from the Upper Bonny Estuary intothis creek The slightly higher Margalef species richness anddominance index at lowwater showed that green algae speciesmight have the ability to sink and settle vertically downwithin the water column thus they were retained in OkpokaCreek at low tide Also this observation might indicate astable green algae community at low tide From Figure 8the dominant cyanophytes genera were Spirulina RivulariaOscillatoria and Anabaena There were 10 salient speciesnamely Spirulina major (6739 plusmn 265) S subsalsa (5372 plusmn790) Rivularia sp (4812 plusmn 1051) Oscillatoria lacustris(4331 plusmn 1010) Anabaena spiroides Spirulina princeps(3827 plusmn 1011) O tenuis (3421 plusmn 1182) and A arnoldii(3265 plusmn 265) Tide had varied influence on these speciesA arnoldii S major and O tenuis were only present at lowtide S affinis O lacustris and Rivularia sp were higher in

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Euglenophyceae phytoplankton speciesD

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)Figure 10 Overall mean values of Euglenophyceae species inOkpoka Creek

distribution at high tide than at low tide while other speciesshowed opposite response to tidal effect (Figure 9)Anabaenaspiroides and Microcystis pulverea are pollution indicatorspecies and were more abundant at low tide These speciesare associated with eutrophic water bodies [56] and mighthave occurred in Okpoka Creek due to the increased influx ofnutrients from anthropogenic inputs Their presence at bothtides except Microcystis pulverea could suggest pollution atboth tides At high tide pollutants from the Upper BonnyEstuary moved into the creek while at low tide pollutantsfrom the different industries and residential buildings werepronounced The mean species similarity index (1841 plusmn308) and dissimilarity index of (8159 plusmn 3349) indicateddifferent distributions of species at low and high tides Therewas a higher insignificant dissimilarity index at low tide(8262 plusmn 343) than at high tide (7829 plusmn 694) (119875 gt 005)

46 Euglenophyceae (Euglenoid Flagellates) Euglenophyceaeaccounted for 085 (the least) of the phytoplankton pop-ulation Insignificant higher density of algae (10574 plusmn1955 nomL) was recorded at low tide than at high tide(6863 plusmn 1778 nomL) (119875 gt 005) Diversity indices weresignificantly higher at high tide than at low tide (119875 lt005) Shannon index was insignificantly higher at low tidewhile evenness index was significantly higher at low tide(119875 lt 005 DMR) This indicated that euglenoid speciesdiversity was higher and unevenly distributed at high tideThis might be attributed to tidal turbulence owning to theinflow of sea water into the creek Three genera and 6species namely Phacus acuminata (8095 plusmn 375) Euglenagracilis (7674 plusmn 861) E acus (5572 plusmn 1572) E viridis(5432plusmn932) E wangi (5909plusmn000) and Trachelomonasafricana (5714 plusmn 000) were observed (Figure 10) Tide


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Figure 11 Variations of Euglenophyceae species in relation to tidein Okpoka Creek

had significant different effects on these species (119875 lt 005)(Figure 11)

P acuminata and E gracilis were higher at low tide thanat high tide T africana E viridis and E wangi were absentat low tide Only one species (E acus) was higher at hightide (7143 plusmn 000) than at low tide (4000 plusmn 000) Eacus E gracilis E viridis E wangi and Phacus acuminataare implicated to organic matter Organic matter and ironare implicated to be among the ecological factors that affectthe euglenoids [51] Pollution by dissolved organic nutrientsis best interpreted by the saprobic system The presence ofhigher abundance of E acus at high tide might be a pointerthat Okpoka Creek is undergoing deterioration especially athigh waterThe influx of sea water from the sea via the BonnyEstuary brings in effluents from the numerous industries andwaterfront dwellers sited along the water course The meansimilarity index was 807 plusmn 337 and dissimilarity index9193 plusmn 459 Tide had no significant effect on similarityand dissimilarity indices Species composition of euglenoidflagellates was dissimilar between the low tide (9018 plusmn687) and high tide (9043 plusmn 558)

47 Pyrrophyceae (Dinoflagellates) Dinoflagellates account-ed for 252 of the phytoplankton abundance and rangedbetween 27700 plusmn 6580 nomL (low tide) and 31457 plusmn11799 nomL (high tide) with a mean of 28674 plusmn 5646 nomL Tidal influence on dinoflagellates parameters was insig-nificant (119875 gt 005) Other parameters ranged betweenlow tide and high tide as follows Margalef (019 plusmn 009 and026 plusmn 013) Shannon (008 plusmn 003 and 013 plusmn 006) Evenness

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Figure 12 Overall mean values of Pyrrophyceae species in OkpokaCreek

(012 plusmn 005 and 019 plusmn 009) and Dominance (013 plusmn 005and 021 plusmn 010) Two genera and 4 species of dinoflagellateswere observed (Figure 12) They were Ceratium furca(10000 plusmn 000) C hirudinella (8142 plusmn 111) Perid-inium cinctum (4973 plusmn 1270) andP umbonatum (10000 plusmn000) Figure 13 shows that C furca and P umbonatumwere present only at low tide The absence of these species athigh tide might probably be adduced to tidally phototacticvertical migration pattern and endogenous tidal rhythm [4]Before high tide these organisms disappeared swimmingdown and attaching themselves to the dark underside of solidobjects so as not to be affected by the high water or rise inwater level C hirudinella distribution percentage was high athigh tide (8044 plusmn 1957) than at low tide (8175 plusmn 829)P cinctum tidal mean ranged between 3913 plusmn 000 (hightide) and 5238 plusmn 1603 (low tide) These species that werepresent at both tides could indicate resilience of these algaeThe observed higher abundances of dinoflagellates at lowtide could suggest passive transport process and it is themain factor controlling the permanence of these species Inaddition the ability these algae to grow at a faster rate mightbe the possible reason Dinoflagellates have the capacityfor rapid cell division with growth rates up to 27 dayminus1based on equivalent body mass [4] Ceratium furca has beenimplicated to organic pollution

The mean similarity index ranged from 000 plusmn 000to 3900 plusmn 1812 with a mean of 1808 plusmn 664 anddissimilarity index ranged from 6100 plusmn 1812 to 10000 plusmn000 with a mean of 8192 plusmn 751 The ANOVA showedno significant differences Tide had no significant effecton similarity and dissimilarity indices of dinoflagellatesSimilarity index ranged between 1232 plusmn 485 (low tide)and 4000 plusmn 2450 (high tide) while dissimilarity index was6000 plusmn 2450 (high tide) and 8768 plusmn 686 (low tide)


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Figure 13 Variation of Pyrrophyceae species in relation to tide inOkpoka Creek

48 Xanthophyceae (Xanthophytes) Xanthophytes densityranged significantly between 109703 plusmn 10382 nomL (lowtide) and 237264 plusmn 24352 nomL (high tide) (119875 lt 005DMR) The mean diversity indices were significantly high(DMR) at low tide than at high tide as follows Margalef003 plusmn 002 and 014 plusmn 002 Shannon 004 plusmn 002 and 009 plusmn001 Evenness 004 plusmn 003 and 013 plusmn 002 and Dominance005 plusmn 016 and 016 plusmn 002 Passive transport processadvection cycle settling and resuspension that follow thesuspended particles during the ebb slack and flood tidalstages could be the possible reasons for this observation Lowtide similarity and dissimilarity indices were 3868 plusmn 557and 6132 plusmn 562 respectively while high tide similarity anddissimilarity indices were 1340 plusmn 716 and 8660 plusmn 716respectively Tidal influences on these indices were notsignificant (119875 gt 005 DMR) This indicated that xantho-phytes were not similarly distributed at low tide

One genus and 2 species of xanthophyceae namelyTribonema viride (5321 plusmn 1058) and T vulgare (8155 plusmn633) were observed (Figure 14) From Figure 15 high tidedistribution percentages were significantly higher than thatof low tide percentages of abundance of species (119875 lt 005DMR) T viride had distribution percentages of 5029 plusmn1139 at low tide and 6490 plusmn 3511 at high tide T vulgarehad distribution percentages of 7985 plusmn 737 at low tide and9007 plusmn 993 at high tide

49 Chrysophyceae (Chrysophytes) Chrysophytes rangedinsignificantly (119875 gt 005 DMR) from 12425 plusmn 3399 nomL

Xanthophyceaephytoplankton

Tribonemavulgare 8155


Tribonemaviride 5321

Tribonema virideTribonema vulgare

Figure 14 Overall mean values of Xanthophyceae species inOkpoka Creek

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ion

()

Figure 15 Variation of Xanthophyceae species in relation to tide inOkpoka Creek

(high tide) to 49531plusmn7933 nomL (low tide) with a mean of457267 plusmn 346 nomL which was 401 total phytoplanktonabundance The possible reasons for this observation aresimilar to those of xanthophytes Also it could indicate thestress condition of Okpoka Creek and that they are notresilient algae All species diversity indices were zero signi-fying very low species diversity Only 1 species Dinobryonsertularia was observed This might mean similarity index(1515 plusmn 634) and dissimilarity index (8485 plusmn 634)of chrysophytes were recorded Tide had no significanteffects on similarity and dissimilarity indices (119875 gt 005DMR) Dissimilarity index of species was higher at high tideindicating that chrysophytes were differently distributed athigh tide


5 Conclusion

Tide has varied effects on the nutrients status and phyto-plankton community (in terms of species composition diver-sity abundance and distribution) of Okpoka Creek Phos-phate and ammonia (organic pollutants) exceeded FEPAand USEPA acceptable levels of 010mgL and 010mgLrespectively for natural water bodies indicating high nutrientstatus organic matter and potential pollutants in this creekDiatoms are the dominant phytoplankton while euglenoidsare the passive (least) phytoplankters They are sensitive andresilient to both low and high tides Organic pollution indi-cator species Navicula gracilis N cuspidata N placentulaN microcephala N bacillum N amphibola Nitzschia sigmaN bilobata N lanceolata N filiforms N longissima Cym-bella cuspidata C lata Tabellaria fenestrate Synedra ulnaCyclotella meneghiniana Cocconeis placentula Pinnulariamajor (diatoms) Cladophora glomerata Scenedesmus spp(green algae) Euglena acus (euglenoid) Anabaena spiroidesMicrocystis pulverea (blue-green algae) and Ceratium furca(dinoflagellate) were recorded at either only low high or bothtides The flushing action of the tidal flows contributes tomoving these pollutants down into this creek

Recommendation

Tide is a major determinant of tidal variations This studytherefore suggests the high-resolution monitoring programsthat are essential to capture the natural variability of phyto-plankton in coastal waters Concerted environmental surveil-lance on Upper Bonny Estuary is advocated to reducethe inflow of pollutants from the Bonny Estuary into thiscreek caused by tidal influence Aquatic scientists should beencouraged to conduct further researches on tidal effects onother aspects of the biology and ecology of phytoplankton inOkpoka Creek and other tributaries of Bonny Estuary as wellas the Bonny Estuary at large in order to bridge the gap inknowledge of the abiotic and biotic properties of this estuary

References

[1] H Badsi H Oulad Ali M Loudiki and A Aamiri ldquoPhyto-plankton diversity and community composition along thesalinity gradient of the massa estuaryrdquo American Journal ofHuman Ecology vol 1 no 2 pp 58ndash64 2012

[2] B H Wilcox ldquoAngiosperm flora of the Niger Delta mangala taxonomic reviewrdquo in Proceedings of Workshop on the NigerDelta Mangrove Ecosystem pp 19ndash23 Port Harcourt NigeriaOctober 1980

[3] F Villate ldquoTidal influence on zonation and occurrence of resi-dent and temporary zooplankton in a shallow system (Estuaryof Mundaka Bay of Biscay)rdquo Scientia Marina vol 61 no 2 pp173ndash188 1997

[4] J M Trigueros and E Orive ldquoTidally driven distribution ofphytoplankton blooms in a shallowmacrotidal estuaryrdquo Journalof Plankton Research vol 22 no 5 pp 969ndash986 2000

[5] C Riaux-Gobin ldquoPhytoplankton tripton et microphytoben-thos echanges au cours de la maree dans un estuaire du Nord-Finistererdquo Cahiers de Biologie Marine vol 28 pp 159ndash184 1987

[6] L A Morales-Zamorano R Cajal-Medrano E Orellana-Cepeda and L C Jimenez-Perez ldquoEffect of tidal dynamics ona planktonic community in a coastal lagoon of Baja CaliforniaMexicordquoMarine Ecology Progress Series vol 78 no 3 pp 229ndash239 1991

[7] J E Cloern ldquoTidal stirring and phytoplankton bloomdynamicsin an estuaryrdquo Journal ofMarine Research vol 49 no 1 pp 203ndash221 1991

[8] L V Lucas and J E Cloern ldquoEffects of tidal shallowing anddeepening on phytoplankton production dynamics a modelingstudyrdquo Estuaries A vol 25 no 4 pp 497ndash507 2002

[9] A N Blauw E Beninca R W P M Laane N Greenwood andJ Huisman ldquoDancing with the tides fluctuations of coastalphytoplankton orchestrated by different oscillatory modes ofthe tidal cyclerdquo PLoS ONE vol 7 no 11 Article ID e49319 2012

[10] K M Rajesh G Gowda and R M Mridula ldquoPrimary produc-tivity of the brackishwater impoundments along Nethravathiestuary Mangalore in relation to some physico-chemicalparametersrdquo Fishery Technology vol 39 no 2 pp 85ndash87 2002

[11] G Ananthan P Sampathkumar P Soundarapandian and LKannan ldquoObservations on environmental characteristics ofAriyankuppam estuary and Verampattinam coast of Pondi-cherryrdquo Journal of Aquatic Biology vol 19 pp 67ndash72 2004

[12] A Tiwari and S V S Chauhan ldquoSeasonal phytoplanktonicdiversity of Kitham lake Agrardquo Journal of EnvironmentalBiology vol 27 no 1 pp 35ndash38 2006

[13] B Tas and A Gonulol ldquoAn ecologic and taxonomic study onphytoplankton of a shallow lake Turkeyrdquo Journal of Environ-mental Biology vol 28 no 2 pp 439ndash445 2007

[14] A Saravanakumar J Sesh Serebiah G A Thivakaran and MRajkumar ldquoBenthic macrofaunal assemblage in the arid zonemangroves of gulf of Kachchh-Gujaratrdquo Journal of OceanUniversity of China vol 6 no 3 pp 303ndash309 2007

[15] P Ponmanickam T Rajagopal M K Rajan S Achiraman andK Palanivelu ldquoAssessment of drinking water quality of Vem-bakottai reservoir Virudhunagar district Tamil Nadurdquo Journalof Experimental Zoology vol 10 no 2 pp 485ndash488 2007

[16] T R Shashi Shekhar B R Kiran E T Puttaiah Y ShivarajandKMMahadevan ldquoPhytoplankton as index of water qualitywith reference to industrial pollutionrdquo Journal of EnvironmentalBiology vol 29 no 2 pp 233ndash236 2008

[17] AmericanPublicHealthAssociation (APHA) StandardMethodfor the Examination of Water and WasteWater McGraw-HillWashington DC USA 16th edition 1985

[18] C E BoydWater Quality in Warmwater Fish Ponds Craftmas-ter Auburn Alabama USA 2nd edition 1981

[19] J G Needham and P R Needham A Guide to the Study ofFreshwater Biology Holden-Day San Francisco Calif USA 2ndedition 1962

[20] G E Newell and R C Newell Marine Plankton A PracticalGuide Hutchinson Publishing Limited London UK 1st edi-tion 1963

[21] R Patrick andC ReimerTheDiatoms of theUnited States Exclu-sive Alaska and Hawaii T Fragillariaceae Eunoticeae Achnan-thaceaeNaviculaceae Livingstone Philadelphia PaUSA 1966

[22] M Han Illustration of Freshwater Plankton Agricultural PressAuburn Alabama USA 1st edition 1978

[23] J R Durans and C Leveque ldquoFlore et farune aquatiquesde 1afrique-an-off erchrdquo Science Technica Qutre-Mer vol 1 pp 5ndash46 1980


[24] GW PrescottHow to Know the Freshwater Algae McGrawHillWashington DC USA 1982

[25] M O Kadiri ldquoA taxonomic study of the genus Closterium(Nizch 1919) Ralfs 1945 (Desmichaceae Chlorophyta) in smallNigeria Reservoir with ecological notesrdquo Tropical FreshwaterBiology vol 1 pp 71ndash90 1988

[26] E P Odum Fundamentals of Ecology WB Saunders LondonUK 3rd edition 1971

[27] Statistical Analysis System (SAS) Userrsquos Guide SASSTA-Tversion SAS Institute Cary NC USA 8th edition 2003

[28] M Yamamuro I Koike and H Iizumi ldquoPartitioning of thenitrogen stock in the vicinity of a Fijian seagrass bed dominatedby Syringodium isoetifolium (Ascherson) Dandyrdquo AustralianJournal of Marine amp Freshwater Research vol 44 no 1 pp 101ndash115 1993

[29] R V Thurston R C Russo and G A Vinogradov ldquoAmmoniatoxicity to fishes Effect of pH on the toxicity of the un-ionizedammonia speciesrdquo Environmental Science and Technology vol15 no 7 pp 837ndash840 1981

[30] R N McNeely V P Neimanis and L Dwyer Water QualitySourcebook A Guide to Water Quality Parameters InlandWaters Directorate Water Quality Branch Ottawa Canada1979

[31] Environmental Studies Board (ESB) ldquoWater quality criteria1972rdquo Committee of Water Quality Criteria Report EPA-R3-73-033 Environmental Protection Agency Washington DC USA1973

[32] A C Chindah andU Nduaguibe ldquoEffect of tank farmwastewa-ter onwater quality and periphyton of Lower BonnyRiverNigerDelta Nigeriardquo Journal of Nigeria Environmental Society vol 1no 2 pp 206ndash222 2003

[33] C C Obunwo S A Braide W A L Izonfuo and A CChindah ldquoInfluence of urban activities on the water qualityof a fresh water stream in the Niger Delta Nigeriardquo Journal ofNigerian Environmental Society vol 2 no 2 pp 196ndash209 2004

[34] L Zimmerman ldquoPhytoplankton-national estuarine researchreserverdquo 2013 httpnerrsnoaagovdocsiteprofileacebasinhtmlbioresphy

[35] T A Frankovich E E Gaiser J C Zieman and A HWachnicka ldquoSpatial and temporal distributions of epiphyticdiatoms growing on Thalassia testudinum Banks ex Konigrelationships to water qualityrdquoHydrobiologia vol 569 no 1 pp259ndash271 2006

[36] J Creswell R Karasack R Johnson and H Shayler ldquoNitrogenand phosphorus in limitation in Mill and Green ponds andthe effects of nutrient enrichmentrdquo Macalester EnvironmentalReview 2001

[37] PM Vitousek and RWHowarth ldquoNitrogen limitation on landand in the sea how can it occurrdquo Biogeochemistry vol 13 no2 pp 87ndash115 1991

[38] European Economic Community (EEC) ldquoCouncil directive onthe quality of freshwater needing protection or improvementin order to support fish liferdquo Offshore Journal of EuropeanCommununities L259 pp 1ndash10 1979

[39] United States Environmental Protection Agency (USEPA)ldquoNitrate-Waterrdquo 2000 httpwaterepagovtyperslmonitor-ingvms57cfm

[40] United States Geological Survey (USGS) ldquoNutrients in theNationrsquos WatersmdashToo Much of a Good Thingrdquo 2013 httppubsusgsgovcirccirc1136circ1136html

[41] N EbereThe impact of oil refinery effluents on the distributionabundance and community structure of macro-benthos in OkrikaCreek [PhD thesis] Department of Biological Sciences Riversstate University of Science and Technology 2002

[42] A J Edoghotu The ecological quotients (EQ) of point sourceof pollution along Okpoka Creek Port Harcourt [MS thesis]Department of Biological Sciences Rivers State University ofScience and Technology 1998

[43] A C Chindah and R I Keremah ldquoPhysico-chemistry andphytoplankton of a brackish water fish pond of the BonnyEstuary Nigeriardquo African Journal of Environmental Studies vol2 no 2 pp 63ndash67 2001

[44] A C Chindah and S A Braide ldquoCrude oil spill and the phyto-plankton community of a swamp forest streamrdquoAfrican Journalof Environmental Studies vol 2 no 1 pp 1ndash8 2001

[45] A C Chindah and S A Braide ldquoThe physico-chemical qualityand phytoplankton community of tropical waters a case of4 Biotopes in the Lower Bonny River Niger Delta NigeriardquoCaderno de Pesquisa vol 16 no 2 pp 7ndash35 2004

[46] K A Moser G M MacDonald and J P Smol ldquoApplications offreshwater diatoms to geographical researchrdquo Progress in Physi-cal Geography vol 20 no 1 pp 21ndash52 1996

[47] U Krumme and T H Liang ldquoTidal-induced changes in acopepod-dominated zooplankton community in a macrotidalmangrove channel in northern Brazilrdquo Zoological Studies vol43 no 2 pp 404ndash414 2004

[48] D L Roelke R M Errera R Riesling et al ldquoEffects of nutrientenrichment on Prymnesium parvum population dynamics andtoxicity results from field experiments Lake PossumKingdomUSArdquo Aquatic Microbial Ecology vol 46 no 2 pp 125ndash1402007

[49] S I Passy R W Bode D M Carlson andM A Novak ldquoCom-parative environmental assessment in the studies of benthicdiatom macroinvertebrate and fish communitiesrdquo Interna-tional Review of Hydrobiology vol 89 no 2 pp 121ndash138 2004

[50] D U Okpuruka ldquoTidal and semi-lunar variations in the sur-face phytoplankton of a Port Harcourt mangrove creekrdquo inProceedings of the Workshop on Nigerian Wetlands T V IAkpata and D U U Okali Eds pp 1ndash183 Lagos NigeriaAugust 1986

[51] D I Nwankwo and A Akinsoji ldquoPeriphyton algae of aeutrophic Creek and their possible use as indicatorrdquo NigerianJournal of Botany vol 1 pp 47ndash54 1988

[52] D I Nwankwo and A O Onitiri ldquoPeriphyton community onsubmerged aquatic macrophytes (Hornwort and Bladderwort)in Epe Lagoon Nigeriardquo Journal of Agricultural Science Technol-ogy vol 2 no 2 pp 135ndash141 1992

[53] D I Nwankwo and S A Amuda ldquoPeriphytic diatoms on threefloating aquatic macrophytes in a polluted south-west Nigeriancreekrdquo International Journal of Ecology amp Environmental Sci-ences vol 19 no 1 pp 1ndash10 1993

[54] D I Nwankwo ldquoHydrochemical properties and bottom-dwell-ing diatoms of a Lagos lagoon sewage disposal siterdquo PolskieArchiwum Hydrobiologii vol 41 no 1 pp 35ndash47 1994

[55] D I Nwankwo and K A Kasumu-Iginla ldquoContributions to thediatom flora of Nigeria 11 Tube-dwelling pinnate diatoms fromLagos Molesrdquo Nigeria Journal of Botany vol 10 pp 61ndash69 1997

[56] D I Nwankwo ldquoSeasonal changes in phytoplankton composi-tion and diversity in the Epe lagoon Nigeriardquo Acta Hydrobiol-ogy vol 40 no 2 pp 83ndash92 1998

Submit your manuscripts athttpwwwhindawicom

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Anatomy Research International

PeptidesInternational Journal of


Hindawi Publishing Corporation httpwwwhindawicom

International Journal of

Volume 2014

Zoology


Molecular Biology International

GenomicsInternational Journal of


The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014


BioinformaticsAdvances in

Marine BiologyJournal of



Signal TransductionJournal of


BioMed Research International

Evolutionary BiologyInternational Journal of



Biochemistry Research International

ArchaeaHindawi Publishing Corporationhttpwwwhindawicom Volume 2014


Genetics Research International


Advances in

Virolog y

Hindawi Publishing Corporationhttpwwwhindawicom

Nucleic AcidsJournal of

Volume 2014

Stem CellsInternational



Enzyme Research



Microbiology


systems [3] Tidal flushing is one of the main bottom-up fac-tors controlling phytoplankton biomass in estuaries besidesnutrients [4]Quite a number ofworks had been conducted toevaluate tidal control of plants and animals communities andprocesses in different systems These include tide-inducedphytoplankton and microphytobenthos exchanges [5] tidalinfluence on bacteria microphytoplankton and microzoo-plankton abundance [6] tidal stirring and phytoplanktonbloom dynamic in an estuary [7] tidal influence on zonationand occurrence of resident and temporary zooplankton inMundaka Estuary Bay of Biscay [3] and effects of tidalshallowing and deepening on phytoplankton productiondynamics a modeling study [8] and dancing with the tidesfluctuations of coastal phytoplankton orchestrated by differ-ent oscillatory modes of the tidal cycle [9]

Phytoplankton populations are highly dynamic and inmany environments they experience episodes of rapid bio-mass increase (blooms) either as recurrent seasonal events oras higher frequency phenomena [7] According to Badsi [1]Rajesh et al [10] Ananthan et al [11] Tiwari and Chauhan[12] Tas andGonulol [13] and Saravanakumar et al [14] phy-toplanktonic organism is one of the initial biological compo-nents from which the energy is transferred to higher organ-isms through food chain The density and the diversity ofphytoplankton are biological indicators for evaluating waterquality and the degree of eutrophication [1 15 16]

There are many human activities going on around andin the creek such as slaughtering of animal transportation(boating navigation) fishing and waste disposal Howeverthere has been no information on the influence of tide on thenutrients status and phytoplankton community of OkpokaCreek a tidal tributary of Upper Bonny Estuary In order tobridge the existing gap in knowledge of the biotic and abioticfeatures of this estuary there is therefore the need to provideuseful information on the tidal variations of water nutrientsand phytoplankton population of this Creek Based on thisthe study thus evaluated the influence of low and high tideson nutrients abundance species composition diversity anddistribution of the phytoplankton of Okpoka Creek

2 Materials and Methods

21 Study Area Okpoka Creek is located between longi-tudes 7∘0010158401015840E and 7∘1510158401015840N and latitudes 4∘2810158401015840E and 4∘4010158401015840N(Figure 1) The vegetation is dominated by nypa palm (Nypafrutican) and mangroves red mangrove (Rhizophora race-mosa) and white mangrove (Avicennia nitida) It passesthrough many communities namely Oginigba Woji andAzubiae Many manrsquos activities going on within and aroundthis creek include dredging fishing boating navigationwashing disposal of excreta bathing and swimming tomention but a few This aquatic body receives effluentdischarges from the many industries (Snig Far East paintsRIVOC General-agro Michelin tyres Coca Cola Hallibur-ton Schlumberger Acorn etc) andmain abattoir house sitedclose to itThe stretch of the coastal front of the creek has veryhigh population density without wastemanagement facilities

All the industries in the Trans-Amadi Industrial Layout andthe riverine dwellers discharge their wastes directly to thiscreek

22 Sampling Stations A total of ten stations were chosen atleast 500 metres apart along the main creek course Thesestations were Station 1 (Oginigba) Station 2 (Trans-Amadiby Schlumberger) Station 3 (bymain abattoir house) Station4 (Azubiae) Station 5 (Woji) Station 6 (Okujagu) Station 7(Okuru-ama) Station 8 (Ojimba) Station 9 (Oba-ama) andStation 10 (Kalio-ama) There are many industries sited closeto the river shore discharging effluents into the creek Thedominant vegetation is nypa palm (Nypa frutican) followedby drying up red mangrove Patches of water hyacinth wereseen during the rainy season Manual dredging of sand isconstantly going on

23 Physicochemical Parameters of the Water The followingparameters weremeasured in situ and in laboratory followingstandard methods [17] One-litre clean containers were usedto collect water samples for physicochemical parametersat each station All the kegs containers were kept in ice-chest box for laboratory analyses Nitrate was determinedby the Brucine method [17] Spectrophotometer (spectronic21D) was used to measure the nitrate at 410 nm wavelengthSulphate determination was carried out by turbidimetricprocedure [17] This involved the use of spectrophotometer(Spectronic 21D) The concentration of sulphate (mgL) wasmeasured thus

Sulphate =mgSO

4

times 1000


Phosphate-in-water levels were determined by standardtest [17] It involved the use of spectrophotometer (Spectronic21D) The concentration of phosphate (mgL) was measuredthus

Phosphate =mgPO

4

times 1000


Ammonia concentrations in water samples were deter-mined by the indophenol or phenate (phenol-hypochlorite)method It was spectrophotometrically measured at 630 nmwavelength with spectronic 21D [17] The concentrationof total ammonia in the samples was computed from theequation

1198621

1198622

=1198601

1198602

(3)

where 1198601= the absorbance of the total ammonia-nitrogen

standard 1198602= the absorbance of the sample and 119862

1= the

concentration of the total ammonia-nitrogen standard 1198622=

the concentration of total ammonia nitrogen in the sample(Boyd [18])




N N

N N

N N

NN NN






(4)



119867 =119878 minus 1

In119873 (5)






119862 = sum(119899119894

119873)

2

(6)




119878 =2119862

119860 + 119861 (7)





119867 = sum(119899119894




119890 =119867

log119890

119878 (10)


3 Data Analyses



Tide Ammonia(mgL)

Nitrate(mgL)















7166

8

1672

97

457

26

382

31

964

6

286

74 1330

48

0

1000

2000

3000

4000

5000

6000

7000

8000

Den

sity

(No

mL)

Baci

llario

phyc

eae

Chlo

roph

ycea

e

Chry

soph

ycea

e

Cyan

ophy

ceae

Eugl

enop

hyce

ae

Pyrr

ophy

ceae

Xant

hoph

ycea

e

Phytoplankton class





Low tide High tide



0

1000

2000

3000

4000

5000

6000

7000

8000

9000

Den

sity

(No

ml)

Phyto

plank

ton c

lass




Xanthophyceae




0

02

04

06

08

1

12

14

16

Mar

gale

f ind

ex

Baci

llario

phyc

eae

Chlo

roph

ycea

e

Chry

soph

ycea

e

Cyan

ophy

ceae

Eugl

enop

hyce

ae

Pyrr

ophy

ceae

Xant

hoph

ycea

e

Phytoplankton class

Low tideHigh tide






0

01

02

03

04

05

06

07

08

09

Shan

non

inde

x

Baci

llario

phyc

eae

Chlo

roph

ycea

e

Chry

soph

ycea

e

Cyan

ophy

ceae

Eugl

enop

hyce

ae

Pyrr

ophy

ceae

Xant

hoph

ycea

e

Phytoplankton class

Low tideHigh tide



0

005

01

015

02

025

03

035

04

045

Even

ness

inde

x

Baci

llario

phyc

eae

Chlo

roph

ycea

e

Chry

soph

ycea

e

Cyan

ophy

ceae

Eugl

enop

hyce

ae

Pyrr

ophy

ceae

Xant

hoph

ycea

e






0

005

01

015

02

025

Dom

inan

ce in

dex

Baci

llario

phyc

eae

Chlo

roph

ycea

e

Chry

soph

ycea

e

Cyan

ophy

ceae

Eugl

enop

hyce

ae

Pyrr

ophy

ceae

Xant

hoph

ycea

e





































Table 3 Continued














a3868 plusmn 557

a1232 plusmn 485

b1724 plusmn 714

a982 plusmn 419

a



a1340 plusmn 716

a4000 plusmn 2450

a0000 plusmn 000

a957 plusmn 650

a


b5625 plusmn 339

a8262 plusmn 343

a6132 plusmn 562

a8768 plusmn 686

a8276 plusmn 714

a9018 plusmn 687

a



a8660 plusmn 716

a6000 plusmn 2450

a10000 plusmn 000

a9043 plusmn 558

a







119875 lt 005


119875 lt 005





119875 lt 005



119875 lt 005















0102030405060708090

1 3 5 7 9 11 13 15 17 19 21

Dist

ribut

ion

()



0102030405060708090

1 3 5 7 9 11 13 15 17 19 21

Dist

ribut

ion

()


LowDry



0

10

20

30

40

50

60

70

80

90

Phac

us a

cum

inat

a

Trac

helo

mon

asaf

rican

a

Eugle

na a

cus

Eugle

na gr

acili

s

Eugle

na v

iridi

s

Eugle

na w

angi


istrib

utio

n (





0

20

40

60

80

100

120

Phac

usac

umin

ata

Trac

helo

mon

asaf

rican

a

Eugle

na a

cus

Eugle

nagr

acili

s

Eugle

na v

iridi

s

Eugle

na w

angi


Dist

ribut

ion

()

LowHigh





0

20

40

60

80

100

120

Cera

tium

furc

a

Cera

tium

hiru

dine

lla

Perid

iniu

m ci

nctu

m

Perid

iniu

mum

bona

tum


Dist

ribut

ion

()





0

20

40

60

80

100

120

Low High

Tide



Dist

ribut

ion

()











0

20

40

60

80

100

120

140

Low HighTide


Dist

ribut

ion

()




5 Conclusion


Recommendation


References

































































Volume 2014

Zoology






















Advances in

Virolog y



Volume 2014




Enzyme Research



Microbiology




N N

N N

N N

NN NN






(4)



119867 =119878 minus 1

In119873 (5)






119862 = sum(119899119894

119873)

2

(6)




119878 =2119862

119860 + 119861 (7)





119867 = sum(119899119894




119890 =119867

log119890

119878 (10)


3 Data Analyses



Tide Ammonia(mgL)

Nitrate(mgL)















7166

8

1672

97

457

26

382

31

964

6

286

74 1330

48

0

1000

2000

3000

4000

5000

6000

7000

8000

Den

sity

(No

mL)

Baci

llario

phyc

eae

Chlo

roph

ycea

e

Chry

soph

ycea

e

Cyan

ophy

ceae

Eugl

enop

hyce

ae

Pyrr

ophy

ceae

Xant

hoph

ycea

e

Phytoplankton class





Low tide High tide



0

1000

2000

3000

4000

5000

6000

7000

8000

9000

Den

sity

(No

ml)

Phyto

plank

ton c

lass




Xanthophyceae




0

02

04

06

08

1

12

14

16

Mar

gale

f ind

ex

Baci

llario

phyc

eae

Chlo

roph

ycea

e

Chry

soph

ycea

e

Cyan

ophy

ceae

Eugl

enop

hyce

ae

Pyrr

ophy

ceae

Xant

hoph

ycea

e

Phytoplankton class

Low tideHigh tide






0

01

02

03

04

05

06

07

08

09

Shan

non

inde

x

Baci

llario

phyc

eae

Chlo

roph

ycea

e

Chry

soph

ycea

e

Cyan

ophy

ceae

Eugl

enop

hyce

ae

Pyrr

ophy

ceae

Xant

hoph

ycea

e

Phytoplankton class

Low tideHigh tide



0

005

01

015

02

025

03

035

04

045

Even

ness

inde

x

Baci

llario

phyc

eae

Chlo

roph

ycea

e

Chry

soph

ycea

e

Cyan

ophy

ceae

Eugl

enop

hyce

ae

Pyrr

ophy

ceae

Xant

hoph

ycea

e






0

005

01

015

02

025

Dom

inan

ce in

dex

Baci

llario

phyc

eae

Chlo

roph

ycea

e

Chry

soph

ycea

e

Cyan

ophy

ceae

Eugl

enop

hyce

ae

Pyrr

ophy

ceae

Xant

hoph

ycea

e





































Table 3 Continued














a3868 plusmn 557

a1232 plusmn 485

b1724 plusmn 714

a982 plusmn 419

a



a1340 plusmn 716

a4000 plusmn 2450

a0000 plusmn 000

a957 plusmn 650

a


b5625 plusmn 339

a8262 plusmn 343

a6132 plusmn 562

a8768 plusmn 686

a8276 plusmn 714

a9018 plusmn 687

a



a8660 plusmn 716

a6000 plusmn 2450

a10000 plusmn 000

a9043 plusmn 558

a







119875 lt 005


119875 lt 005





119875 lt 005



119875 lt 005















0102030405060708090

1 3 5 7 9 11 13 15 17 19 21

Dist

ribut

ion

()



0102030405060708090

1 3 5 7 9 11 13 15 17 19 21

Dist

ribut

ion

()


LowDry



0

10

20

30

40

50

60

70

80

90

Phac

us a

cum

inat

a

Trac

helo

mon

asaf

rican

a

Eugle

na a

cus

Eugle

na gr

acili

s

Eugle

na v

iridi

s

Eugle

na w

angi


istrib

utio

n (





0

20

40

60

80

100

120

Phac

usac

umin

ata

Trac

helo

mon

asaf

rican

a

Eugle

na a

cus

Eugle

nagr

acili

s

Eugle

na v

iridi

s

Eugle

na w

angi


Dist

ribut

ion

()

LowHigh





0

20

40

60

80

100

120

Cera

tium

furc

a

Cera

tium

hiru

dine

lla

Perid

iniu

m ci

nctu

m

Perid

iniu

mum

bona

tum


Dist

ribut

ion

()





0

20

40

60

80

100

120

Low High

Tide



Dist

ribut

ion

()











0

20

40

60

80

100

120

140

Low HighTide


Dist

ribut

ion

()




5 Conclusion


Recommendation


References

































































Volume 2014

Zoology






















Advances in

Virolog y



Volume 2014




Enzyme Research



Microbiology





119862 = sum(119899119894

119873)

2

(6)




119878 =2119862

119860 + 119861 (7)





119867 = sum(119899119894




119890 =119867

log119890

119878 (10)


3 Data Analyses



Tide Ammonia(mgL)

Nitrate(mgL)















7166

8

1672

97

457

26

382

31

964

6

286

74 1330

48

0

1000

2000

3000

4000

5000

6000

7000

8000

Den

sity

(No

mL)

Baci

llario

phyc

eae

Chlo

roph

ycea

e

Chry

soph

ycea

e

Cyan

ophy

ceae

Eugl

enop

hyce

ae

Pyrr

ophy

ceae

Xant

hoph

ycea

e

Phytoplankton class





Low tide High tide



0

1000

2000

3000

4000

5000

6000

7000

8000

9000

Den

sity

(No

ml)

Phyto

plank

ton c

lass




Xanthophyceae




0

02

04

06

08

1

12

14

16

Mar

gale

f ind

ex

Baci

llario

phyc

eae

Chlo

roph

ycea

e

Chry

soph

ycea

e

Cyan

ophy

ceae

Eugl

enop

hyce

ae

Pyrr

ophy

ceae

Xant

hoph

ycea

e

Phytoplankton class

Low tideHigh tide






0

01

02

03

04

05

06

07

08

09

Shan

non

inde

x

Baci

llario

phyc

eae

Chlo

roph

ycea

e

Chry

soph

ycea

e

Cyan

ophy

ceae

Eugl

enop

hyce

ae

Pyrr

ophy

ceae

Xant

hoph

ycea

e

Phytoplankton class

Low tideHigh tide



0

005

01

015

02

025

03

035

04

045

Even

ness

inde

x

Baci

llario

phyc

eae

Chlo

roph

ycea

e

Chry

soph

ycea

e

Cyan

ophy

ceae

Eugl

enop

hyce

ae

Pyrr

ophy

ceae

Xant

hoph

ycea

e






0

005

01

015

02

025

Dom

inan

ce in

dex

Baci

llario

phyc

eae

Chlo

roph

ycea

e

Chry

soph

ycea

e

Cyan

ophy

ceae

Eugl

enop

hyce

ae

Pyrr

ophy

ceae

Xant

hoph

ycea

e





































Table 3 Continued














a3868 plusmn 557

a1232 plusmn 485

b1724 plusmn 714

a982 plusmn 419

a



a1340 plusmn 716

a4000 plusmn 2450

a0000 plusmn 000

a957 plusmn 650

a


b5625 plusmn 339

a8262 plusmn 343

a6132 plusmn 562

a8768 plusmn 686

a8276 plusmn 714

a9018 plusmn 687

a



a8660 plusmn 716

a6000 plusmn 2450

a10000 plusmn 000

a9043 plusmn 558

a







119875 lt 005


119875 lt 005





119875 lt 005



119875 lt 005















0102030405060708090

1 3 5 7 9 11 13 15 17 19 21

Dist

ribut

ion

()



0102030405060708090

1 3 5 7 9 11 13 15 17 19 21

Dist

ribut

ion

()


LowDry



0

10

20

30

40

50

60

70

80

90

Phac

us a

cum

inat

a

Trac

helo

mon

asaf

rican

a

Eugle

na a

cus

Eugle

na gr

acili

s

Eugle

na v

iridi

s

Eugle

na w

angi


istrib

utio

n (





0

20

40

60

80

100

120

Phac

usac

umin

ata

Trac

helo

mon

asaf

rican

a

Eugle

na a

cus

Eugle

nagr

acili

s

Eugle

na v

iridi

s

Eugle

na w

angi


Dist

ribut

ion

()

LowHigh





0

20

40

60

80

100

120

Cera

tium

furc

a

Cera

tium

hiru

dine

lla

Perid

iniu

m ci

nctu

m

Perid

iniu

mum

bona

tum


Dist

ribut

ion

()





0

20

40

60

80

100

120

Low High

Tide



Dist

ribut

ion

()











0

20

40

60

80

100

120

140

Low HighTide


Dist

ribut

ion

()




5 Conclusion


Recommendation


References

































































Volume 2014

Zoology






















Advances in

Virolog y



Volume 2014




Enzyme Research



Microbiology







7166

8

1672

97

457

26

382

31

964

6

286

74 1330

48

0

1000

2000

3000

4000

5000

6000

7000

8000

Den

sity

(No

mL)

Baci

llario

phyc

eae

Chlo

roph

ycea

e

Chry

soph

ycea

e

Cyan

ophy

ceae

Eugl

enop

hyce

ae

Pyrr

ophy

ceae

Xant

hoph

ycea

e

Phytoplankton class





Low tide High tide



0

1000

2000

3000

4000

5000

6000

7000

8000

9000

Den

sity

(No

ml)

Phyto

plank

ton c

lass




Xanthophyceae




0

02

04

06

08

1

12

14

16

Mar

gale

f ind

ex

Baci

llario

phyc

eae

Chlo

roph

ycea

e

Chry

soph

ycea

e

Cyan

ophy

ceae

Eugl

enop

hyce

ae

Pyrr

ophy

ceae

Xant

hoph

ycea

e

Phytoplankton class

Low tideHigh tide






0

01

02

03

04

05

06

07

08

09

Shan

non

inde

x

Baci

llario

phyc

eae

Chlo

roph

ycea

e

Chry

soph

ycea

e

Cyan

ophy

ceae

Eugl

enop

hyce

ae

Pyrr

ophy

ceae

Xant

hoph

ycea

e

Phytoplankton class

Low tideHigh tide



0

005

01

015

02

025

03

035

04

045

Even

ness

inde

x

Baci

llario

phyc

eae

Chlo

roph

ycea

e

Chry

soph

ycea

e

Cyan

ophy

ceae

Eugl

enop

hyce

ae

Pyrr

ophy

ceae

Xant

hoph

ycea

e






0

005

01

015

02

025

Dom

inan

ce in

dex

Baci

llario

phyc

eae

Chlo

roph

ycea

e

Chry

soph

ycea

e

Cyan

ophy

ceae

Eugl

enop

hyce

ae

Pyrr

ophy

ceae

Xant

hoph

ycea

e





































Table 3 Continued














a3868 plusmn 557

a1232 plusmn 485

b1724 plusmn 714

a982 plusmn 419

a



a1340 plusmn 716

a4000 plusmn 2450

a0000 plusmn 000

a957 plusmn 650

a


b5625 plusmn 339

a8262 plusmn 343

a6132 plusmn 562

a8768 plusmn 686

a8276 plusmn 714

a9018 plusmn 687

a



a8660 plusmn 716

a6000 plusmn 2450

a10000 plusmn 000

a9043 plusmn 558

a







119875 lt 005


119875 lt 005





119875 lt 005



119875 lt 005















0102030405060708090

1 3 5 7 9 11 13 15 17 19 21

Dist

ribut

ion

()



0102030405060708090

1 3 5 7 9 11 13 15 17 19 21

Dist

ribut

ion

()


LowDry



0

10

20

30

40

50

60

70

80

90

Phac

us a

cum

inat

a

Trac

helo

mon

asaf

rican

a

Eugle

na a

cus

Eugle

na gr

acili

s

Eugle

na v

iridi

s

Eugle

na w

angi


istrib

utio

n (





0

20

40

60

80

100

120

Phac

usac

umin

ata

Trac

helo

mon

asaf

rican

a

Eugle

na a

cus

Eugle

nagr

acili

s

Eugle

na v

iridi

s

Eugle

na w

angi


Dist

ribut

ion

()

LowHigh





0

20

40

60

80

100

120

Cera

tium

furc

a

Cera

tium

hiru

dine

lla

Perid

iniu

m ci

nctu

m

Perid

iniu

mum

bona

tum


Dist

ribut

ion

()





0

20

40

60

80

100

120

Low High

Tide



Dist

ribut

ion

()











0

20

40

60

80

100

120

140

Low HighTide


Dist

ribut

ion

()




5 Conclusion


Recommendation


References

































































Volume 2014

Zoology






















Advances in

Virolog y



Volume 2014




Enzyme Research



Microbiology


Low tide High tide



0

1000

2000

3000

4000

5000

6000

7000

8000

9000

Den

sity

(No

ml)

Phyto

plank

ton c

lass




Xanthophyceae




0

02

04

06

08

1

12

14

16

Mar

gale

f ind

ex

Baci

llario

phyc

eae

Chlo

roph

ycea

e

Chry

soph

ycea

e

Cyan

ophy

ceae

Eugl

enop

hyce

ae

Pyrr

ophy

ceae

Xant

hoph

ycea

e

Phytoplankton class

Low tideHigh tide






0

01

02

03

04

05

06

07

08

09

Shan

non

inde

x

Baci

llario

phyc

eae

Chlo

roph

ycea

e

Chry

soph

ycea

e

Cyan

ophy

ceae

Eugl

enop

hyce

ae

Pyrr

ophy

ceae

Xant

hoph

ycea

e

Phytoplankton class

Low tideHigh tide



0

005

01

015

02

025

03

035

04

045

Even

ness

inde

x

Baci

llario

phyc

eae

Chlo

roph

ycea

e

Chry

soph

ycea

e

Cyan

ophy

ceae

Eugl

enop

hyce

ae

Pyrr

ophy

ceae

Xant

hoph

ycea

e






0

005

01

015

02

025

Dom

inan

ce in

dex

Baci

llario

phyc

eae

Chlo

roph

ycea

e

Chry

soph

ycea

e

Cyan

ophy

ceae

Eugl

enop

hyce

ae

Pyrr

ophy

ceae

Xant

hoph

ycea

e





































Table 3 Continued














a3868 plusmn 557

a1232 plusmn 485

b1724 plusmn 714

a982 plusmn 419

a



a1340 plusmn 716

a4000 plusmn 2450

a0000 plusmn 000

a957 plusmn 650

a


b5625 plusmn 339

a8262 plusmn 343

a6132 plusmn 562

a8768 plusmn 686

a8276 plusmn 714

a9018 plusmn 687

a



a8660 plusmn 716

a6000 plusmn 2450

a10000 plusmn 000

a9043 plusmn 558

a







119875 lt 005


119875 lt 005





119875 lt 005



119875 lt 005















0102030405060708090

1 3 5 7 9 11 13 15 17 19 21

Dist

ribut

ion

()



0102030405060708090

1 3 5 7 9 11 13 15 17 19 21

Dist

ribut

ion

()


LowDry



0

10

20

30

40

50

60

70

80

90

Phac

us a

cum

inat

a

Trac

helo

mon

asaf

rican

a

Eugle

na a

cus

Eugle

na gr

acili

s

Eugle

na v

iridi

s

Eugle

na w

angi


istrib

utio

n (





0

20

40

60

80

100

120

Phac

usac

umin

ata

Trac

helo

mon

asaf

rican

a

Eugle

na a

cus

Eugle

nagr

acili

s

Eugle

na v

iridi

s

Eugle

na w

angi


Dist

ribut

ion

()

LowHigh





0

20

40

60

80

100

120

Cera

tium

furc

a

Cera

tium

hiru

dine

lla

Perid

iniu

m ci

nctu

m

Perid

iniu

mum

bona

tum


Dist

ribut

ion

()





0

20

40

60

80

100

120

Low High

Tide



Dist

ribut

ion

()











0

20

40

60

80

100

120

140

Low HighTide


Dist

ribut

ion

()




5 Conclusion


Recommendation


References

































































Volume 2014

Zoology






















Advances in

Virolog y



Volume 2014




Enzyme Research



Microbiology


0

01

02

03

04

05

06

07

08

09

Shan

non

inde

x

Baci

llario

phyc

eae

Chlo

roph

ycea

e

Chry

soph

ycea

e

Cyan

ophy

ceae

Eugl

enop

hyce

ae

Pyrr

ophy

ceae

Xant

hoph

ycea

e

Phytoplankton class

Low tideHigh tide



0

005

01

015

02

025

03

035

04

045

Even

ness

inde

x

Baci

llario

phyc

eae

Chlo

roph

ycea

e

Chry

soph

ycea

e

Cyan

ophy

ceae

Eugl

enop

hyce

ae

Pyrr

ophy

ceae

Xant

hoph

ycea

e






0

005

01

015

02

025

Dom

inan

ce in

dex

Baci

llario

phyc

eae

Chlo

roph

ycea

e

Chry

soph

ycea

e

Cyan

ophy

ceae

Eugl

enop

hyce

ae

Pyrr

ophy

ceae

Xant

hoph

ycea

e





































Table 3 Continued














a3868 plusmn 557

a1232 plusmn 485

b1724 plusmn 714

a982 plusmn 419

a



a1340 plusmn 716

a4000 plusmn 2450

a0000 plusmn 000

a957 plusmn 650

a


b5625 plusmn 339

a8262 plusmn 343

a6132 plusmn 562

a8768 plusmn 686

a8276 plusmn 714

a9018 plusmn 687

a



a8660 plusmn 716

a6000 plusmn 2450

a10000 plusmn 000

a9043 plusmn 558

a







119875 lt 005


119875 lt 005





119875 lt 005



119875 lt 005















0102030405060708090

1 3 5 7 9 11 13 15 17 19 21

Dist

ribut

ion

()



0102030405060708090

1 3 5 7 9 11 13 15 17 19 21

Dist

ribut

ion

()


LowDry



0

10

20

30

40

50

60

70

80

90

Phac

us a

cum

inat

a

Trac

helo

mon

asaf

rican

a

Eugle

na a

cus

Eugle

na gr

acili

s

Eugle

na v

iridi

s

Eugle

na w

angi


istrib

utio

n (





0

20

40

60

80

100

120

Phac

usac

umin

ata

Trac

helo

mon

asaf

rican

a

Eugle

na a

cus

Eugle

nagr

acili

s

Eugle

na v

iridi

s

Eugle

na w

angi


Dist

ribut

ion

()

LowHigh





0

20

40

60

80

100

120

Cera

tium

furc

a

Cera

tium

hiru

dine

lla

Perid

iniu

m ci

nctu

m

Perid

iniu

mum

bona

tum


Dist

ribut

ion

()





0

20

40

60

80

100

120

Low High

Tide



Dist

ribut

ion

()











0

20

40

60

80

100

120

140

Low HighTide


Dist

ribut

ion

()




5 Conclusion


Recommendation


References

































































Volume 2014

Zoology






















Advances in

Virolog y



Volume 2014




Enzyme Research



Microbiology


0

005

01

015

02

025

Dom

inan

ce in

dex

Baci

llario

phyc

eae

Chlo

roph

ycea

e

Chry

soph

ycea

e

Cyan

ophy

ceae

Eugl

enop

hyce

ae

Pyrr

ophy

ceae

Xant

hoph

ycea

e





































Table 3 Continued














a3868 plusmn 557

a1232 plusmn 485

b1724 plusmn 714

a982 plusmn 419

a



a1340 plusmn 716

a4000 plusmn 2450

a0000 plusmn 000

a957 plusmn 650

a


b5625 plusmn 339

a8262 plusmn 343

a6132 plusmn 562

a8768 plusmn 686

a8276 plusmn 714

a9018 plusmn 687

a



a8660 plusmn 716

a6000 plusmn 2450

a10000 plusmn 000

a9043 plusmn 558

a







119875 lt 005


119875 lt 005





119875 lt 005



119875 lt 005















0102030405060708090

1 3 5 7 9 11 13 15 17 19 21

Dist

ribut

ion

()



0102030405060708090

1 3 5 7 9 11 13 15 17 19 21

Dist

ribut

ion

()


LowDry



0

10

20

30

40

50

60

70

80

90

Phac

us a

cum

inat

a

Trac

helo

mon

asaf

rican

a

Eugle

na a

cus

Eugle

na gr

acili

s

Eugle

na v

iridi

s

Eugle

na w

angi


istrib

utio

n (





0

20

40

60

80

100

120

Phac

usac

umin

ata

Trac

helo

mon

asaf

rican

a

Eugle

na a

cus

Eugle

nagr

acili

s

Eugle

na v

iridi

s

Eugle

na w

angi


Dist

ribut

ion

()

LowHigh





0

20

40

60

80

100

120

Cera

tium

furc

a

Cera

tium

hiru

dine

lla

Perid

iniu

m ci

nctu

m

Perid

iniu

mum

bona

tum


Dist

ribut

ion

()





0

20

40

60

80

100

120

Low High

Tide



Dist

ribut

ion

()











0

20

40

60

80

100

120

140

Low HighTide


Dist

ribut

ion

()




5 Conclusion


Recommendation


References

































































Volume 2014

Zoology






















Advances in

Virolog y



Volume 2014




Enzyme Research



Microbiology






























Table 3 Continued














a3868 plusmn 557

a1232 plusmn 485

b1724 plusmn 714

a982 plusmn 419

a



a1340 plusmn 716

a4000 plusmn 2450

a0000 plusmn 000

a957 plusmn 650

a


b5625 plusmn 339

a8262 plusmn 343

a6132 plusmn 562

a8768 plusmn 686

a8276 plusmn 714

a9018 plusmn 687

a



a8660 plusmn 716

a6000 plusmn 2450

a10000 plusmn 000

a9043 plusmn 558

a







119875 lt 005


119875 lt 005





119875 lt 005



119875 lt 005















0102030405060708090

1 3 5 7 9 11 13 15 17 19 21

Dist

ribut

ion

()



0102030405060708090

1 3 5 7 9 11 13 15 17 19 21

Dist

ribut

ion

()


LowDry



0

10

20

30

40

50

60

70

80

90

Phac

us a

cum

inat

a

Trac

helo

mon

asaf

rican

a

Eugle

na a

cus

Eugle

na gr

acili

s

Eugle

na v

iridi

s

Eugle

na w

angi


istrib

utio

n (





0

20

40

60

80

100

120

Phac

usac

umin

ata

Trac

helo

mon

asaf

rican

a

Eugle

na a

cus

Eugle

nagr

acili

s

Eugle

na v

iridi

s

Eugle

na w

angi


Dist

ribut

ion

()

LowHigh





0

20

40

60

80

100

120

Cera

tium

furc

a

Cera

tium

hiru

dine

lla

Perid

iniu

m ci

nctu

m

Perid

iniu

mum

bona

tum


Dist

ribut

ion

()





0

20

40

60

80

100

120

Low High

Tide



Dist

ribut

ion

()











0

20

40

60

80

100

120

140

Low HighTide


Dist

ribut

ion

()




5 Conclusion


Recommendation


References

































































Volume 2014

Zoology






















Advances in

Virolog y



Volume 2014




Enzyme Research



Microbiology


Table 3 Continued














a3868 plusmn 557

a1232 plusmn 485

b1724 plusmn 714

a982 plusmn 419

a



a1340 plusmn 716

a4000 plusmn 2450

a0000 plusmn 000

a957 plusmn 650

a


b5625 plusmn 339

a8262 plusmn 343

a6132 plusmn 562

a8768 plusmn 686

a8276 plusmn 714

a9018 plusmn 687

a



a8660 plusmn 716

a6000 plusmn 2450

a10000 plusmn 000

a9043 plusmn 558

a







119875 lt 005


119875 lt 005





119875 lt 005



119875 lt 005















0102030405060708090

1 3 5 7 9 11 13 15 17 19 21

Dist

ribut

ion

()



0102030405060708090

1 3 5 7 9 11 13 15 17 19 21

Dist

ribut

ion

()


LowDry



0

10

20

30

40

50

60

70

80

90

Phac

us a

cum

inat

a

Trac

helo

mon

asaf

rican

a

Eugle

na a

cus

Eugle

na gr

acili

s

Eugle

na v

iridi

s

Eugle

na w

angi


istrib

utio

n (





0

20

40

60

80

100

120

Phac

usac

umin

ata

Trac

helo

mon

asaf

rican

a

Eugle

na a

cus

Eugle

nagr

acili

s

Eugle

na v

iridi

s

Eugle

na w

angi


Dist

ribut

ion

()

LowHigh





0

20

40

60

80

100

120

Cera

tium

furc

a

Cera

tium

hiru

dine

lla

Perid

iniu

m ci

nctu

m

Perid

iniu

mum

bona

tum


Dist

ribut

ion

()





0

20

40

60

80

100

120

Low High

Tide



Dist

ribut

ion

()











0

20

40

60

80

100

120

140

Low HighTide


Dist

ribut

ion

()




5 Conclusion


Recommendation


References

































































Volume 2014

Zoology






















Advances in

Virolog y



Volume 2014




Enzyme Research



Microbiology






119875 lt 005


119875 lt 005





119875 lt 005



119875 lt 005















0102030405060708090

1 3 5 7 9 11 13 15 17 19 21

Dist

ribut

ion

()



0102030405060708090

1 3 5 7 9 11 13 15 17 19 21

Dist

ribut

ion

()


LowDry



0

10

20

30

40

50

60

70

80

90

Phac

us a

cum

inat

a

Trac

helo

mon

asaf

rican

a

Eugle

na a

cus

Eugle

na gr

acili

s

Eugle

na v

iridi

s

Eugle

na w

angi


istrib

utio

n (





0

20

40

60

80

100

120

Phac

usac

umin

ata

Trac

helo

mon

asaf

rican

a

Eugle

na a

cus

Eugle

nagr

acili

s

Eugle

na v

iridi

s

Eugle

na w

angi


Dist

ribut

ion

()

LowHigh





0

20

40

60

80

100

120

Cera

tium

furc

a

Cera

tium

hiru

dine

lla

Perid

iniu

m ci

nctu

m

Perid

iniu

mum

bona

tum


Dist

ribut

ion

()





0

20

40

60

80

100

120

Low High

Tide



Dist

ribut

ion

()











0

20

40

60

80

100

120

140

Low HighTide


Dist

ribut

ion

()




5 Conclusion


Recommendation


References

































































Volume 2014

Zoology






















Advances in

Virolog y



Volume 2014




Enzyme Research



Microbiology


0102030405060708090

1 3 5 7 9 11 13 15 17 19 21

Dist

ribut

ion

()



0102030405060708090

1 3 5 7 9 11 13 15 17 19 21

Dist

ribut

ion

()


LowDry



0

10

20

30

40

50

60

70

80

90

Phac

us a

cum

inat

a

Trac

helo

mon

asaf

rican

a

Eugle

na a

cus

Eugle

na gr

acili

s

Eugle

na v

iridi

s

Eugle

na w

angi


istrib

utio

n (





0

20

40

60

80

100

120

Phac

usac

umin

ata

Trac

helo

mon

asaf

rican

a

Eugle

na a

cus

Eugle

nagr

acili

s

Eugle

na v

iridi

s

Eugle

na w

angi


Dist

ribut

ion

()

LowHigh





0

20

40

60

80

100

120

Cera

tium

furc

a

Cera

tium

hiru

dine

lla

Perid

iniu

m ci

nctu

m

Perid

iniu

mum

bona

tum


Dist

ribut

ion

()





0

20

40

60

80

100

120

Low High

Tide



Dist

ribut

ion

()











0

20

40

60

80

100

120

140

Low HighTide


Dist

ribut

ion

()




5 Conclusion


Recommendation


References

































































Volume 2014

Zoology






















Advances in

Virolog y



Volume 2014




Enzyme Research



Microbiology


0

20

40

60

80

100

120

Phac

usac

umin

ata

Trac

helo

mon

asaf

rican

a

Eugle

na a

cus

Eugle

nagr

acili

s

Eugle

na v

iridi

s

Eugle

na w

angi


Dist

ribut

ion

()

LowHigh





0

20

40

60

80

100

120

Cera

tium

furc

a

Cera

tium

hiru

dine

lla

Perid

iniu

m ci

nctu

m

Perid

iniu

mum

bona

tum


Dist

ribut

ion

()





0

20

40

60

80

100

120

Low High

Tide



Dist

ribut

ion

()











0

20

40

60

80

100

120

140

Low HighTide


Dist

ribut

ion

()




5 Conclusion


Recommendation


References

































































Volume 2014

Zoology






















Advances in

Virolog y



Volume 2014




Enzyme Research



Microbiology


0

20

40

60

80

100

120

Low High

Tide



Dist

ribut

ion

()











0

20

40

60

80

100

120

140

Low HighTide


Dist

ribut

ion

()




5 Conclusion


Recommendation


References

































































Volume 2014

Zoology






















Advances in

Virolog y



Volume 2014




Enzyme Research



Microbiology


5 Conclusion


Recommendation


References

































































Volume 2014

Zoology






















Advances in

Virolog y



Volume 2014




Enzyme Research



Microbiology










































Volume 2014

Zoology






















Advances in

Virolog y



Volume 2014




Enzyme Research



Microbiology








Volume 2014

Zoology






















Advances in

Virolog y



Volume 2014




Enzyme Research



Microbiology

Documents

Research Article Tidal Influence on Nutrients Status and ...downloads.hindawi.com/journals/jmb/2013/684739.pdfJournalof Marine Biology L.G.A boundary Local government headquarters