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Climate Change Impacts: Vegetation And Plant Responses In Gujarat
144
Chapter 5: Identifying Tree Species with Maximum Carbon Sequestration Capabilities as Future Sinks of Carbon in the Scenario
of Changing Climate.
Azadirachta indica A Juss tree with a girth of 4.1 m
Bombax ceiba L with a girth of 3 m
Figure-32: Largest trees of Gujarat University Campus
Climate Change Impacts: Vegetation And Plant Responses In Gujarat
145
Introduction
CO2 emissions
Anthropogenic activities, especially fossil fuel burning and land use changes
(Pandey, 2002) are currently responsible for an annual emission of 9 Gt C (33 Gt
CO2). Terrestrial and oceanic systems manage to absorb 3 and 2 Gt of this
anthropogenic C release, respectively, but the rest, 4 Gt, remains in the atmosphere
(Kumar et al., 2009; Jansson et al., 2010) which have resulted in an increase in the
concentration of GHGs particularly CO2 (Jina et al, 2008). Since the beginning of the
industrial revolution, carbon dioxide concentration in the atmosphere has been rising
alarmingly. Prior to the industrial revolution carbon concentration was around
270ppm which increased to 372ppm in 2005 (Kumar et al., 2006; Ramachandran et
al., 2007). The rising level of atmospheric CO2 is believed to cause global warming
at an alarming rate of 0.2°C per decade with an estimated average rise in global
temperature of 3°C by 2100 (Hamburg et al., 1997; Phani Kumar et al., 2009; Jana et
al., 2009; Lavania and Lavania, 2009; Chavan, 2010). Impact of climate change on
the ecology, economy and society is increasing (Pandey, 2002).
CO2 mitigation options
Carbon dioxide is among the most important anthropogenic greenhouse gases
(Houghton et al., 1991). Potential actions to mitigate fossil fuel emissions include
increased energy conservation and efficiency, employment of renewable energy
systems and use of alternative fuels. Other greenhouse gas mitigation options include
sequestration of CO2 in biologic sinks such as plant biomass. For example, C can be
sequestered in trees and durable forest products, in agronomic crops, in halophytes
(salt-tolerant plants), as organic matter in soil, and in marine plants such as
microalgae for decades or centuries (Wisniewskil et al., 1993; Moura-Costa et al.,
1994).
The problem of anthropogenic carbon dioxide accumulation in the atmosphere can
be addressed either by reducing CO2 emission or by developing carbon sinks. The
Kyoto Protocol of the UN framework convention on climate change (UNFCCC) was
Climate Change Impacts: Vegetation And Plant Responses In Gujarat
146
the first step taken by the international community in this direction. For developing
carbon sinks, much of the emphasis was given at Kyoto pertained to afforestation
and reforestation programmes (Ravindranath et al., 1997; Jina et al., 2008). Large
scale reforestation can offset fossil fuel based CO2 emissions. It is suggested that the
global climate problem could be solved by planting a total of 500 million hectares of
plantations even without parallel efforts to minimize carbon emissions from fossil
fuel combustion. CO2 emissions from deforestation are about 2 billion tC/year over
three times the emission from motor cars (Baral and Guha, 2004).
Jansson et al., (2010) has included the statement of Freeman Dyson (2008) which
states that, “If we can control what the plants do with carbon, the fate of the carbon
in the atmosphere is in our hands.”
Forests as carbon sinks
Global carbon is held in a variety of different stocks. Natural stocks include oceans,
fossil fuel deposits, the terrestrial system and the atmosphere. In the terrestrial
system carbon is sequestered in rocks and sediments, in swamps, wetlands and
forests, and in the soils of forests, grasslands and agriculture. About two-thirds of the
globe’s terrestrial carbon, exclusive of that sequestered in rocks and sediments, is
sequestered in the standing forests, forest under-storey plants, leaf and forest debris,
and in forest soils (Warran & Patwardhan, 2001).
Global carbon (C) cycling depends largely on the photosynthetic uptake of
atmospheric carbon dioxide (CO2). The total C stock (i.e., organic and inorganic C)
in terrestrial systems is estimated to be around 3170 gigatons, 2500 Gt in the soil and
560 Gt and 110 Gt in plant and microbial biomass, respectively. Total C in the
oceans is 38,000 Gt (Tuskan and Walsh, 2001; Lal, 2004, 2008; Houghton, 2007).
The soil C pool, which is 3.3 times the size of the atmospheric C pool of 760 Gt,
includes about 1550 Gt of soil organic carbon (SOC) and 950 Gt of soil inorganic
carbon (SIC) (Lal 2004, 2008). Of the C present in the world’s biota, 99.9% is
contributed by vegetation and microbial biomass; animals constitute a negligible C
reservoir (Jana et al., 2009; Jansson et al, 2010).
Climate Change Impacts: Vegetation And Plant Responses In Gujarat
147
Forests play a significant role in climate change as it emits as well as sequesters CO2.
Trees absorb atmospheric CO2 for their growth and also increase the carbon content
in the soil as well. Revitalizing degraded forest lands and soils in the global
terrestrial ecosystem can sequester 50-70% of the historic losses. Forests play a
profound role in reducing ambient CO2 levels as they sequester 20-100 times more
carbon per unit area than croplands (Karky and Banskota, 2006).
A substantial amount of C can be sequestered in plant biomass. As about 90% of the
world’s terrestrial C is stored in forests, forest plantations and the preservation of old
forests are of chief importance in controlling the size of the overall terrestrial C sink
(Jansson et al., 2010). Carbon capture and sequestration through forests can play an
important role in reducing India’s GHG emissions. Managing forests to sequester
carbon has a combined advantage of producing woods and conserving biodiversity
while preventing soil erosion. Absorbing CO2 from air and transferring it into the
biomass could be a cost effective and practical way of removing large volumes of
GHGs from the atmosphere. It has been estimated that managing the world’s
vegetation could turn the terrestrial biosphere from a source of carbon (0.1-4.2 Pg
carbon per year) to a carbon sink (1.3-3 Pg carbon per year) (Mohapatra, 2008).
Forest ecosystem plays very important role in the global carbon cycle. It stores about
80% of all above-ground and 40% of all below-ground terrestrial organic carbon
(Houghton et al., 2001, Sulistyawati et al., 2007). During productive season, CO2
from the atmosphere is taken up by vegetation (Losi et al., 2003) and stored as plant
biomass (Samalca et al., 2007). However the global forest cover is declining at an
alarming rate as about 13 million hectares of global forests are lost annually (Singh
and Lodhiyal, 2009)
Current estimate of annual terrestrial plant uptake of C due to CO2 fertilization are
within the range 0.5-2.0×1015g, which is about 8-33% of annual fossil fuel
emissions. Currently, total aboveground biomass in the world’s forest is 421×109
tonnes distributed over 3869 Mha. Of this, 3682×106 ha or 95% is natural forest and
187×106 ha or 5% is plantation area. Forests store 1200 GtC in vegetation and soil
globally. C in forest constitutes 54% of the 2200 Gt of the total C pool in terrestrial
ecosystem. Forests sequester 1-3 GtC annually through the combined effect of
Climate Change Impacts: Vegetation And Plant Responses In Gujarat
148
reforestation, regeneration and enhanced growth of existing forest, offsetting the
global CO2 emissions from deforestation. Terrestrial and marine environment are
currently absorbing about half of the CO2 that is emitted by fossil fuel combustion
(Pandey, 2002). The total aboveground and below ground biomass in the Indian
forest has been estimated as 6865.1 and 1818.7 Mt contributing 79 and 21% to the
total biomass respectively. The C pool for the Indian forest has been estimated to be
2026.72 Mt for the year 1995. Further mitigation of about 3.32 Gt in the next 50
years at an annual reduction of about 0.072 Gt of C is possible (Pandey, 2002).
Lal et al. (2000) reported that estimated annual carbon uptake increment by Indian
forests and plantations have been able to remove about 0.125 Gt of CO2 from the
atmosphere in the year 1995. Ravindranath et al. (1997) reported the Indian forests
based on the forest sector of the year 1986 could sequester around 5 Tg C (1 Tg
=Tera gram, 10-12 g). Haripriya (2003) noted on the average biomass carbon of the
forest ecosystems in India for the year 1994 was 46 Mg C ha-1, of which nearly 76%
was in aboveground biomass and the rest was in fine and coarse root biomass (Jana
et al., 2009).
Vegetation as Carbon Sink
Carbon sequestration involves the capture and storage of the carbon from the
atmosphere which would otherwise go on accumulating in the atmosphere. Carbon
dioxide is captured and stored naturally by the plants by the process of
photosynthesis where they take in CO2 and sequester it in the form of sugars and
finally contribute to organic matter in the soil (Kumar et al., 2006; Phani Kumar et
al., 2009). Hence, estimation of this C content both in vegetation and in soil becomes
imperative to access the Carbon sequestration potential. Later on, the glucose in trees
gets converted to other forms of food material, i.e. starch, lignin, hemicelluloses,
amino acids, protein, etc. and is diverted to other tree components for storage. It is a
well-established fact that food is stored either in the roots or bole and branches.
Generally, the plants allocate more of the energy in the root system under stress
conditions and in the aboveground components in normal conditions (Negi et al.,
2003). This results in an increase in their biomass, indicative of an increase in carbon
Climate Change Impacts: Vegetation And Plant Responses In Gujarat
149
sequestered by them (Kumar et al., 2006; Ramachandran et al., 2007; Jana et al.,
2009; Jeff and Hill, 2009). In the case of carbon sequestration in a permanent stand,
the C accumulation rate in above ground biomass is linear initially but declines due
to saturation effect. Carbon sequestered in soil and litter over 100 years represents
about 20% of carbon sequestered in aboveground biomass in the case of direct
sequestration (Baral and Guha, 2004). Soil-vegetation systems play an important role
in the global carbon cycle. Soil contains about three times more organic carbon than
vegetation and about twice as much carbon than is present in the atmosphere.
Vegetation stands next only to soil in sequestering carbon (Dinakaran et al., 2008;
Kumar et al., 2006; Batjes & Sombroek, 1997). Plants can contribute to mitigate
GHE and global warming. Terrestrial vegetation and soil currently absorb 40% of
global CO2 emission from human activities (Sheikh and Kumar, 2010).
Carbon sequestration by trees
Tree, shrub, soil and sea water play crucial role in absorbing atmospheric carbon
dioxide (Chavan, 2010). Trees act as a sink for CO2 by fixing carbon during
photosynthesis and storing excess carbon as biomass. The net long term CO2
source/sink dynamics of forests change through time as trees grow, die and decay. In
addition, human influences on forests can further affect CO2 source/sink dynamics of
forests through such factors as fossil fuel emissions and harvesting/utilization of
biomass (Nowak and Crane, 2002). As the tree biomass experience growth, the
carbon held by the plant also increases carbon stock. The rate of carbon storage
increases in young stands, but then declines as the stand ages. An observation from a
study on pine species planted on cropland in the southeastern U.S., the rate of carbon
storage begins to decline at approximately age 20 and is close to zero by 100.
Increasing the atmospheric CO2 concentration stimulates the photosynthetic rate of
trees and can result in increased growth rates and biomass production. Results from
free air CO2 enrichment (FACE) experiments show a 25% increase in growth in
twice normal concentrations of CO2. Growth is therefore almost always higher in air
with an elevated concentration of CO2 (Burley et al., 2004). Scientific evidence
suggests that increased atmospheric CO2 could have positive effect such as improved
Climate Change Impacts: Vegetation And Plant Responses In Gujarat
150
plant productivity (Schaffer et al., 1997; Pan et al., 1998; Centritto et al., 1999; Idso
and Kimball, 2001; Keutgen and Chen, 2001; Jana et al., 2009)
Biological fixation of CO2 is an attractive option because plants naturally capture
and use CO2 as a part of the photosynthetic process. Terrestrial plants sequester vast
amounts of CO2 from the atmosphere (Khan, 2008). Meanwhile, plants have the
ability to absorb carbon dioxide for carbonxylation and subsequently for production
of carbohydrates (especially by the tuberous plants) and for production of woods and
fibres (by trees) through photosynthesis. Photosynthesis is the major process by
which plants produced carbohydrates, and the major ingredient in this process is
carbon dioxide (Abdulrahaman and Oladeley, 2008). As trees grow and their
biomass increases, they absorb carbon from the atmosphere and store it in the plant
tissues (Mathews et al., 2000) resulting in growth of different parts. Active
absorption of CO2 from the atmosphere in photosynthetic process and its subsequent
storage in the biomass of growing trees or plants is the carbon storage (Baes et al.,
1977). In terms of atmospheric carbon reduction, trees in urban areas offer the
double benefit of direct carbon storage and stability of natural ecosystem with
increased recycling of nutrient along with maintenance of climatic conditions by the
biogeochemical processes (Chavan, 2010). Plants can play two fundamentally
different roles as C sinks. By capturing atmospheric CO2 through photosynthesis
plants store large amounts of organic C in above and belowground biomass. This is
particularly relevant for perennial trees and herbaceous plants with extensive root
systems (Jansson et al., 2010). Biological growth involves the shifting of carbon
from one stock to another. Plants fix atmospheric carbon in cell tissues as they grow,
thereby transforming carbon from the atmosphere to the biotic system (Warran &
Patwardhan, 2001).
Trees take atmospheric CO2 during photosynthesis and fix it in woody (branches,
stem and woody roots) and non-woody (foliage and fine roots) parts (Baral and
Guha, 2004). The trees act as major CO2 sink which captures carbon from the
atmosphere and acts as sink, stores the same in the form of fixed biomass during the
growth process. Therefore, growing trees in urban areas can be a potential
Climate Change Impacts: Vegetation And Plant Responses In Gujarat
151
contributor in reducing the concentration of CO2 in atmosphere by its accumulation
in the form of biomass (Chavan, 2010).
Factors influencing carbon sequestration capacity of trees
Forests are the large terrestrial reservoir for atmospheric carbon. They remove CO2
from the atmosphere and store it in the organic matter of the soil and trees. The
amount of carbon stored in the forest depends on its age and productivity (Sheikh
and Kumar, 2010). The concept of sequestering atmospheric carbon by forestry is
based on the principle that trees extract CO2 from the atmosphere in the process of
photosynthesis, and use it to produce structural compounds for their growth. The
amount of carbon stored in trees in a forest can be calculated by determining the
amount of biomass in the forest and applying a conversion factor. As longer-lived,
high density trees store more carbon than short-lived, low density, fast-growing trees
or other vegetation, enrichment planting logged forests with hardwood trees make it
possible to obtain dense stands which accumulate higher amounts of carbon per area
than logged forests which are left untreated (Moura-Costa et al., 1994).
The rate of carbon sequestration depends on the growth characteristics of the tree
species, the conditions for growth where the tree is planted, and the density of the
tree’s wood (Jana et al., 2009). Ability of the terrestrial biosphere to sequester and
store atmospheric CO2 has been recognized as an effective and low cost method of
offsetting carbon emissions. C sequestration potential differs with the kind of land
use. It is a proven fact that forest ecosystems are the best way to sequester carbon.
Carbon sequestration depends upon the biomass production capacity, which in turn
depends upon interaction between edaphic, climatic and topographic factors of the
area (Koul and Panwar, 2008). The potential of individual trees to act as a C sink
may be highly dependent on response to soil nutrition and environmental stress
rather than to atmospheric CO2 concentration (Norby et al., 1992; Wisniewskil et al.,
1993). Carbon storage is linked with the site quality, nature of the land use, choice of
species and other crop management practices adopted (Koul and Panwar, 2008). The
variation in carbon sequestration capacity of plantations depended on DBH, height,
number of branches and crown canopy of individual plants. Increase in annual
Climate Change Impacts: Vegetation And Plant Responses In Gujarat
152
productivity of plantations directly indicates an increase in forest biomass and hence
higher carbon sequestration potential (Phani Kumar et al., 2009). The amount of
carbon sequestered by trees depends on the biomass accumulation rate and rotation
length (Baral and Guha, 2004). The carbon sequestration capacity of a tree species
depends upon its age, height, girth size, biomass accumulation capacity, canopy
diameter and most important wood specific density (Rathore and Jasrai, 2013).
Climate Change Impacts: Vegetation And Plant Responses In Gujarat
153
Literature Review
Carbon sequestration
Concern about an enhanced greenhouse effect has prompted several attempts to
calculate the net release of CO2 to the atmosphere resulting from deforestation
(Emanuel et al., 1984; Houghton et al., 1991; Houghton 1991). Similar efforts have
been made to calculate the amount of CO2 that can be sequestered by planting trees
(Cooper, 1983; Cropper and Ewe1, 1984; Thompson and Matthews, 1989). Workers
have variously concentrated on the amount of carbon stored in the living trees
(Cooper, 1983; Johnson and Sharpe, 1983; Matthews et al., 1991), the wood
products (Row and Phelps, 1990), the tree-soil ecosystem (Cropper and Ewe1, 1984),
or the trees and wood products (Thompson and Matthews, 1989). Few studies have
encompassed the entire tree-soil-products system, and few have tracked the flow of
carbon from the trees to soils and products in a dynamic fashion, as outlined in a
model proposed by Dewar (1991).
Carbon sequestration involves the capture of carbon dioxide from the atmosphere
and storage in the plant tissue in the form of carbohydrates by the process of
photosynthesis (Kumar et al., 2006; Phani Kumar et al., 2009). The biomass of the
tree also increases and can be computed to know the amount of carbon sequestered.
There are many destructive and non-destructive methods to compute it which have
been developed through centuries.
Moura-Coasta (1996) worked on the carbon sequestration potential of the
Dipterocarp forest ecosystem in tropical forestry practices in New Jersey.
MacDicken (1997) analysed and constructed a guide for monitoring carbon storage
in forestry and agroforestry, USA. Ramachandran et al., (2007) estimated the carbon
stock of wood biomass and soil in natural forest using geospacial technology in the
Eastern Ghats of Tamil Nadu, India. Phani Kumar et al., (2009) analysed the carbon
stock of willow and poplar species by non-destructive method and also organic
carbon in soil samples in the Nubra valley, Ladakh, India. Jana et al., (2009)
measured the carbon sequestration rate and above ground biomass carbon potential
of four young species of Shorea robusta, Albizzia lebbek, Tectona grandis and
Climate Change Impacts: Vegetation And Plant Responses In Gujarat
154
Artocarpus integrifolia by the non destructive method in West Bengal and observed
that carbon sequestration rate of Albizzia lebbek was higher than Shorea robusta
followed by A. integrifolia and T. grandis.
Chan (1982), Chaturvedi and Singh (1987) and Rawat and Singh (1988) determined
the below ground biomass to be 25% of the above ground biomass. Of the total
carbon stored in the 8-year-old Poplar plantation, 78.68% carbon was allocated in the
above ground components whereas 21.32 % carbon was allocated in the below
ground components of the trees.
Total carbon stock of a tree has been evaluated by adding all the carbon contents of
stems, branches and leaves of the tree (Jana et al., 2009; Phani Kumar et al., 2009).
Trees are important sinks for atmospheric carbon i.e. carbon dioxide, since 50% of
their standing biomass is carbon itself (Ravindranath et al., 1997; Warran &
Patwardhan, 2001). Most of the information for carbon estimation described in the
literature suggests that carbon constitutes between 45 to 50 percent of dry matter
(Schlesinger, 1991; Chan, 1982) and it can be estimated by simply taking a fraction
of biomass as C = 0.475 × B. Where C is the carbon content and B is oven dry
biomass (Singh and Lodhiyal, 2009).
Chan (1982), Pettersen (1984), Losi et al., (2003), Koul and Panwar, (2008) analysed
the carbon percentage of the wood to be 50% of the total biomass. Work of Losi et
al., (2003) obtained that measured carbon content of dry sample was 47.8% for A.
excelsum and 48.5% for D. panamensis. West (2003) reported in his paper that
extensive studies in Australia recently of a variety of tree species showed that above
ground dry biomass generally contain 50% carbon. These proportions of carbon in
aboveground biomass agreed closely with values of 49% and 47% reported from
other parts of the world for Pinus taeda (Kinerson et al., 1977) and Populus spp.
(Deraedt and Ceulemans, 1998) (Jana et al., 2009). The carbon content of vegetation
is surprisingly constant across a wide variety of species.
A field experiment conducted by Mutanal et al., (2007) to assess the performance of
10 multipurpose tree species (viz., Casuarina equisetifolia, Eucalyptus tereticornis,
Grevillea robusta, Tectona grandis, Dalbergia sissoo, Anogeissus latifolia, Albizia
lebbek, Hardwickia binata, Azadirachta indica and Acacia nilotica) suitable for
Climate Change Impacts: Vegetation And Plant Responses In Gujarat
155
agroforestry system in degraded gravelly soils at Main Agricultural Research Station,
University of Agricultural Sciences, Dharwad during the year 1990.
The observations of Negi et al., (2003) revealed that the wood, which constitutes
maximum portion of total biomass, stored maximum amount of carbon. While
comparing the different life forms, it was observed that the maximum carbon is
stored in the order of conifers > deciduous > evergreen > bamboos. Thus it can be
said that the conifers are more efficient in carbon sequestration.
The study investigated by Sheikh and Kumar (2010) with respect to the species
composition and tree carbon stock in two different aspects (northern and southern) of
sub-tropical regions in the Garhwal Himalayas showed that northern aspect have
more carbon sequestration potential especially conifers (Pinus dominant) than that of
broadleaved forest (dominant Anogeissus latifolia) on the southern aspect.
Utilization of biomass as a substitute for fossil fuels is one method to minimize
greenhouse gas emissions Trees also can be used to help conserve energy in urban
areas. Strategic planting of shade trees in cities with substantial air condtioning
requirements can reduce energy use and fossil fuel CO2 emissions. Similarly, trees
may also serve as wind breaks and reduce winter heating needs by 4 to 22%. Akbari
et al., (1988) asserted that urban trees are 15 times more important in reducing CO2
build-up than rural trees. It has been estimated that improving the existing urban
forests in the United States could result in lowering total C emissions by 1 to 3 %
(Sampson et al., 1992; Wisniewskil et al., 1993).
Climate Change Impacts: Vegetation And Plant Responses In Gujarat
156
Significance of the study
In the present day scenario, the enhancement of atmospheric CO2 coupled with the
rise in temperature is the main reason behind the global climate change which has
evidently raised the global mean temperature by 0.5°C during the last hundred years
and 0.4°C in the last 70 years for the Indian sub-continent (Negi et al., 2003). Global
warming risks from emissions of greenhouse gases (GHGs) by anthropogenic
activities have increased the need for the identification of ecosystems (Phani Kumar
et al., 2009; Chavan, 2010) and classifying the plant species for their efficient
responses to enhanced CO2 to climate change in terms of high carbon sink capacity
as an alternative mitigation strategy of terrestrial carbon sequestration (Negi et al.,
2003).
Climate Change Impacts: Vegetation And Plant Responses In Gujarat
157
Material and Method
Study area
Figure-33: Google image of Gujarat University Campus, the study site
Gujarat University, situated in Ahmedabad (Fig-33) has a campus which spreads
over an area of 1.1km2. It is situated between 23°02'11.44"N latitude and
72°32'46.63"E longitude at an elevation of 180 feet. It is subjected to a dry semi-arid
type of the climate according to the Koppen system of classification. The average
summer minimum to maximum temperature varies from 23 to 45°C. The south-
western monsoon results in a humid climate from mid-June to mid-September and
the average annual rainfall is about 76cms.
Methods of tree biomass computation
Trees of ≥ 30cm dbh were considered for the biomass computation.
For the carbon stock estimation, each tree was measured for its height, bole, GBH
(girth at breast height) and diameter of the canopy.
The height of the tree was measured using Haga’s Altimeter. The GBH and canopy
diameter were measured using a measuring tape (Fig-34).
Total sequestered carbon stock of the trees was therefore measured by non-
destructive method using equations involving the total volume, total biomass,
percentage of carbon sequestered and wood density of the plants studied.
Climate Change Impacts: Vegetation And Plant Responses In Gujarat
The total biomass was determined by analyzing both the above ground biomass
(AGB), below ground biomass (BGB) and tree canopy biomass values specific to
each tree species.
The AGB was measured by calculating the volume of the above ground plant and
wood density (Phani
BGB was determined as per the method of
accordance with the work and result of
Singh (1988).
The biomass of foliage cover of each tree was determined with the he
volume calculation (
The total volume is then multiplied by the specific density of the tree to get the total
biomass (Chowdhury
The carbon percentage of the trees was calculated by
by 50% (Chan 1982;
Climate Change Impacts: Vegetation And Plant Responses In Gujarat
ass was determined by analyzing both the above ground biomass
(AGB), below ground biomass (BGB) and tree canopy biomass values specific to
each tree species.
The AGB was measured by calculating the volume of the above ground plant and
Phani Kumar et al., 2009).
was determined as per the method of MacDicken,
the work and result of Chaturvedi and Singh (1
The biomass of foliage cover of each tree was determined with the he
volume calculation (Phani Kumar et al., 2009).
The total volume is then multiplied by the specific density of the tree to get the total
(Chowdhury and Ghosh, 1958, 1963).
The carbon percentage of the trees was calculated by multiplying the total biomass
Chan 1982; Pettersen, 1984; Jina et al., 2008).
Climate Change Impacts: Vegetation And Plant Responses In Gujarat
158
ass was determined by analyzing both the above ground biomass
(AGB), below ground biomass (BGB) and tree canopy biomass values specific to
The AGB was measured by calculating the volume of the above ground plant and
MacDicken, (1997) which is in
Chaturvedi and Singh (1987) and Rawat and
The biomass of foliage cover of each tree was determined with the help of crown
The total volume is then multiplied by the specific density of the tree to get the total
multiplying the total biomass
Climate Change Impacts: Vegetation And Plant Responses In Gujarat
159
Terminalia chebula Retz Pithecellobium dulce (Roxb) Bth
Limonia acidissima L Ficus benghalensis L
Tamarindus indica L Ailanthus excelsa Roxb
Syzygium cumini (L) Skeel Azadirachta indica A Juss
Figure-35 a): Trees of Gujarat University campus
Climate Change Impacts: Vegetation And Plant Responses In Gujarat
160
Ficus religiosa L Albizia lebbeck (L) Bth
Terminalia arjuna (Roxb) W & A Eucalyptus globulus Labill
Cassia fistula L Casuarina equisetifolia L
Mimusops elengi L Peltophorum pterocarpum (DC) Baker
Figure-35 b): Trees of Gujarat University Campus
Climate Change Impacts: Vegetation And Plant Responses In Gujarat
161
Result and Discussion
The Gujarat University campus has a rich floral diversity. The main tree species
comprise of Azadirachta indica (neem), Peltophorum ferrugineum (copper pod tree),
Alianthus excelsa (arduso), Ficus sps., Cassia fistula (amaltas), Polialthia longifolia
(asopalav), Limonia acidissima (wood apple) and Pongamia pinnata (karanj).
The total number of trees in the Gujarat University was counted to be 3379
belonging to 60 species comprising 28 families and 47 genera (Fig-35a,b) and their
carbon stock was measured. Azadirachta indica A Juss (910) trees were most
dominant followed by Peltophorum pterocarpum (DC) Baker (752), Polyalthia
longifolia (Sonner) Thwaites (504), Pongamia pinnata (132), Eucalyptus globulus
Labill (97) and Ailanthus excelsa Roxb (89).
The average carbon stock (t) determined for all the 60 tree species (Table-5 and Fig-
36) shows that trees belonging to Terminalia chebula Retz (76.93 t) had the
maximum amount of C stock followed by Pithecellobium dulce (Roxb) Bth (65.88 t)
Limonia acidissima L (61.31 t) , Ficus benghalensis L (54.03 t), Tamarindus indica
L (52.84 t), Morus alba L (47.92 t), Ailanthus excelsa Roxb (43.89 t), Syzygium
cumini (L) Skeel (43.64 t), Azadirachta indica A Juss (43.11 t), F. religiosa L (42.79
t), Albizzia lebbeck (L) Bth (40.57 t) followed by Terminalia arjuna (Roxb) W & A
(38.21 t), Eucalyptus globulus Labill (35.9 t), Mangifera indica L (35.75 t),
Casuarina equisetifolia L (34.59 t) have the maximum carbon sequestration
capability and therefore are ideal selection for sequestering CO2 in the present
scenario to prevent climate change. While the trees like Acacia nilotica (L) Del (2.48
t) and the members of family Palmae like Phoenix sylvestris (L) Roxb (2.18 t),
Roystonea regia (1.24 t), Musa paradisiaca (0.87 t), Dicrostachys cinerea (DC)
(0.63 t) are found to sequester least amount of carbon (Fig-36). Similar work has
been done by Warran and Patwardhan (2001) on trees of Pune city, Mutanal et al.,
(2007) on selected tree species for agroforestry at Dharwad, Karnataka, Jina et al.,
(2008) on the Oak and Pine forest of Central Himalaya, Jana et al., (2009) on
Albizzia lebbek and Shorea robusta trees in West Bengal, Phani Kumar et al., (2009)
on Poplar and Willow tree plantation in Ladakh, Singh and Lodhiyal (2009) on
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162
Populus tree plantation in central Himalaya, Chavan, (2010) on selected 20 tree
species in the University campus at Aurangabad, Maharashtra, India; Chavan and
Rasal, (2012) for Albizzia lebbek and Delonix regia in Aurangabad, Ullah and Al-
Amin (2012) of trees in natural forest of Bangladesh and Mariappan et al., (2012) on
the urban forest in Chennai.
The carbon stock for each and every tree belonging to the 60 tree species in Gujarat
University campus was calculated. The trees based on their girth sizes and also on
the basis of number of tree species in a particular girth range, were divided into
various girth classes (0-30, 31-40, 41-50, 51-60, 61-70, 71-80, 81-90, 91-100, 101-
110, 111-120, 121-130, 131-140, 141-150, 151-160, 161-170, 171-180, 181-190,
191-200, 201-250, 251-300, 301-350, 351-400 cms).
Table-5: Carbon stock of the selected tree species of Gujarat University
Campus.
Family Scientific name of tree No. of Trees
Avg. Carbon stock (t)
Annonaceae Polyalthia longifolia (Sonner) Thwaites 504 9.66
Malvaceae Thespesia populnea (L) Sol ex Correa 6 16.13
Bombacaceae Bombax ceiba L 2 11.64
Sterculiaceae Guazuma ulmifolia Lam 19 9.42
Rutaceae Aegle marmelos (L) Correa 1 15.17
Limonia acidissima L 15 61.31
Simarubiaceae Ailanthus excelsa Roxb 89 43.89
Meliaceae Azadirachta indica A Juss 910 43.11
Rhamnaceae Zizyphus mauritiana Lam 4 27.55
Anacardiaceae Mangifera indica L 3 35.75
Moringaceae Moringa oleifera Lam 44 5.92
Fabaceae Derris indica (Lam) Bennet 132 16.851
Gliricidia sepium (Jacq) Walp 15 9.38
Caesalpinaceae Bauhinia purpurea L 2 11.64
Cassia fistula L 24 28.27
Cassia javanica L var javanica 2 21.75
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Cassia siamea Lam 29 41.66
Delonix elata (L) Gamble 6 39.74
Delonix regia (Boj) 34 23.2
Peltophorum pterocarpum (DC) Baker 752 28.27
Tamarindus indica L 26 52.84
Mimosaceae Acacia auriculiformis A Cunn ex Benth 8 21.94
Acacia nilotica (L) Del 41 2.48
Albizia lebbeck (L) Bth 102 40.58
Albizia odoratissima (L f) Bth 28 15.69
Albizia procera (Roxb) Bth 64 9.58
Dichrostachys cinerea (DC) 7 0.63
Pithecellobium dulce (Roxb) Bth 10 65.88
Prosopis cineraria (L) Druce 17 10.58
Combretaceae Terminalia arjuna (Roxb) W & A 9 38.21
Terminalia catappa L 7 24.08
Terminalia chebula Retz 5 76.928
Myrtaceae Callistemon citrinus (Curtis) Skeel 3 26.37
Eucalyptus globulus Labill 97 35.91
Psidium guazava L 5 4.23
Syzygium cumini (L) Skeel 10 43.64
Sapotaceae Manilkara hexandra (Roxb) Dub 3 13.52
Manilkara zapota (L) van Royen 1 19.14
Mimusops elengi L 14 32.61
Salvadoraceae Salvadora persica L 9 2.93
Apocynaceae Plumeria alba L 7 4.55
Ehretiaceae Cordia dichotoma Forst f 67 23.38
Cordia gharaf (Forsk) Ehrenb & Asch 5 9.53
Bignoniaceae Kigelia pinnata (Jacq) DC 33 31.17
Euphorbiaceae Emblica officinalis Gaertn 8 43.57
Ulmaceae Holoptelea integrifolia (Roxb) Planch 48 15.45
Moraceae Ficus benghalensis L 3 54.03
Ficus hispida Lf 8 12.07
Ficus drupacea Thunb 8 9.74
Ficus religiosa L 22 42.79
Morus alba L 2 47.92
Streblus asper Lour 1 33.05
Climate Change Impacts: Vegetation And Plant Responses In Gujarat
Casuarinaceae
Arecaceae
Zygophyllaceae
Nyctagenaceae
Musaceae
Climate Change Impacts: Vegetation And Plant Responses In Gujarat
Casuarina equsetifolia L
Borassus flabellifer L
Cocos nucifera L
Phoenix sylvestris (L) Roxb
Roystonea regia (H B & K) O F Cook
Zygophyllaceae Balanites roxburghii (L) Del
Bougainvillea spectabilis Willd
Musa paradisiaca L
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164
9 34.59
4 17.36
2 28.68
1 2.18
25 1.24
11 2.43
1 8.46
55 0.87
Climate Change Impacts: Vegetation And Plant Responses In Gujarat
The correlation and regression analysis were then done for all the 60 tree species to
compare the girth class with the carbon stock (t), height (m) and canopy diameter
(m). The average
taken for all the 60 tree species belonging to each girth class. The
plotted showed a linear
vs carbon stock shows a linear positive correlation and regression of R
girth class vs height shows a linear positive correlation and regression of R
Girth class vs canopy diameter also shows a linear positive correlation and
regression of R2= 0.863. The correlation is a little lesser with height than with other
two parameters. But still, t
stock, height and canopy diameter.
Figure-37: Correlation between girth classes and Carbon stock/ height/ canopy
The result shows
increases, resulting in a simultaneous increase in the amount of carbon
tree. The similar work and result has been done by
(2001) found that ther
diameter and leaf area with dbh in San Joaquin Valley street trees.
Climate Change Impacts: Vegetation And Plant Responses In Gujarat
The correlation and regression analysis were then done for all the 60 tree species to
compare the girth class with the carbon stock (t), height (m) and canopy diameter
(m). The average of the carbon stock (t), height (m) and canopy diameter (m) was
taken for all the 60 tree species belonging to each girth class. The
a linear positive correlation in all aspects (Figure
vs carbon stock shows a linear positive correlation and regression of R
girth class vs height shows a linear positive correlation and regression of R
irth class vs canopy diameter also shows a linear positive correlation and
= 0.863. The correlation is a little lesser with height than with other
parameters. But still, the girth classes are positively correlated with the carbon
stock, height and canopy diameter.
: Correlation between girth classes and Carbon stock/ height/ canopy
diameter
that as the girth increases the height and canopy of a tree also
resulting in a simultaneous increase in the amount of carbon
The similar work and result has been done by some researchers. Peper
(2001) found that there was strong correlation (R2 > 0.70) for total height, crown
diameter and leaf area with dbh in San Joaquin Valley street trees.
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165
The correlation and regression analysis were then done for all the 60 tree species to
compare the girth class with the carbon stock (t), height (m) and canopy diameter
(m) and canopy diameter (m) was
taken for all the 60 tree species belonging to each girth class. The scatter graph
(Figure-37). The girth class
vs carbon stock shows a linear positive correlation and regression of R2= 0.903. The
girth class vs height shows a linear positive correlation and regression of R2= 0.798.
irth class vs canopy diameter also shows a linear positive correlation and
= 0.863. The correlation is a little lesser with height than with other
he girth classes are positively correlated with the carbon
: Correlation between girth classes and Carbon stock/ height/ canopy
eight and canopy of a tree also
resulting in a simultaneous increase in the amount of carbon stock of the
some researchers. Peper et al.,
> 0.70) for total height, crown
diameter and leaf area with dbh in San Joaquin Valley street trees. Alamgir and Al-
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166
Amin (2008) in Chittagong forest division of Bangladesh also developed models
using height alone; DBH alone; height and DBH together; height, DBH and wood
density but found poor correlation. A stratified random sample of street trees was
drawn by Peper and McPherson (2012) from 22 U.S. cities municipal tree inventory
and measured to establish relations between tree age (number of years after planting)
and DBH; DBH and tree height, crown height, average crown diameter, and leaf area
and average crown diameter and DBH. Using DBH to predict tree height and crown
diameter showed the strongest correlations of more than 0.8.
From the various girth classes formed, the maximum number of tree species (37) was
found to be in the girth class of 60-70 cm. Hence, the carbon stock, height and
canopy diameter were compared for all these 37 tree species for that particular girth
class (Fig-38).
The carbon stock (t) determined for all the 37 tree species (Fig-38) in the girth class
of 60-70 cms showed that Limonia acidissima L (50.28 t) had the maximum amount
of C stock followed by Terminalia chebula Retz (45.49 t), Mimusops elengi L
(45.28), Morus alba L (43.75 t), Holoptelea integrifolia (Roxb) Planch (37.4 t),
Cassia fistula (37.22 t), Emblica officinalis Gaertn (36 t), Terminalia arjuna (Roxb)
W & A (34.39 t), Albizia lebbeck (L) Bth (33.65 t), Tamarindus indica L (33.4 t),
Pithecellobium dulce (Roxb) Bth (33.39 t), Syzygium cumini (L) Skeel (32.88 t),
Casuarina equisetifolia L (30.25 t), Mangifera indica L (26 t), Ailanthus excelsa
Roxb (23.19 tC), Azadirachta indica A Juss (20.67 t), followed by Eucalyptus
globulus Labill (13.64 t) and F. religiosa L (11.19 t).
This result when compared to the above results for the average carbon stock of 60
tree species shows similarity, but to a certain extent, owing to the variation in the
factors related to height and canopy diameter. The maximum height was reported in
Emblica officinalis Gaertn (13 m) while, minimum height was measured in
Terminalia arjuna (Roxb) W & A (5 m) and Zizyphus sps (5 m). The largest canopy
diameter was measured in Terminalia chebula Retz (12.5 m) and smallest canopy in
Terminalia cadappa (3.63 m). The result shows that all the trees in a similar girth
class do not have the same height or canopy diameter as well as the specific density
Climate Change Impacts: Vegetation And Plant Responses In Gujarat
and hence the carbon stock is also not the same.
maximum carbon stock
Bth, Limonia acidissima
Ailanthus excelsa
Azadirachta indica
A, Eucalyptus globulus
come out to be almost
species and hence
recommended for plantations in the scenario of climate change for a tropical state
like Gujarat.
Figure-38: Carbon stock, height and canopy diameter of the 37 tree species
Jana et al., (2009) measured the carbon sequestration rate and above ground biomass
carbon potential of four young species of
grandis and Artocarpus integrifolia
3.33 t C/ha/yr respectively
C stock 5.22, 6.26, 7.97 and 7.28 t C/ha in the state of West Bengal. This can be
observed that carbon sequestration rate of
robusta followed by
Climate Change Impacts: Vegetation And Plant Responses In Gujarat
and hence the carbon stock is also not the same. But still the first few species
maximum carbon stock like Terminalia chebula Retz, Pithecellobium dulce
Limonia acidissima L, Cassia fistula L, Tamarindus indica
Ailanthus excelsa Roxb, Syzygium cumini (L) Skeel, Emblica officinalis
Azadirachta indica A Juss, Albizia lebbeck (L) Bth, Terminalia arjuna
Eucalyptus globulus Labill, Mangifera indica L and Casuarina equsetifolia
almost the same, as the result above, with respect to the 60 tree
and hence, these tree species can be considered as ultimate tree species to be
recommended for plantations in the scenario of climate change for a tropical state
: Carbon stock, height and canopy diameter of the 37 tree species
within the girth class of 60-70 cms
(2009) measured the carbon sequestration rate and above ground biomass
of four young species of Shorea robusta, Albi
Artocarpus integrifolia and was estimated to be 8.97, 11.9
respectively; % C content 47.45, 47.12, 45.45 and 43.33
C stock 5.22, 6.26, 7.97 and 7.28 t C/ha in the state of West Bengal. This can be
observed that carbon sequestration rate of Albizia lebbek was higher than
followed by A. integrifolia and T. grandis.
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167
But still the first few species with
Pithecellobium dulce (Roxb)
Tamarindus indica L, Morus alba L,
Emblica officinalis Gaertn,
Terminalia arjuna (Roxb) W &
Casuarina equsetifolia L
with respect to the 60 tree
imate tree species to be
recommended for plantations in the scenario of climate change for a tropical state
: Carbon stock, height and canopy diameter of the 37 tree species
(2009) measured the carbon sequestration rate and above ground biomass
Albizia lebbek, Tectona
and was estimated to be 8.97, 11.97, 2.07 and
; % C content 47.45, 47.12, 45.45 and 43.33 respectively;
C stock 5.22, 6.26, 7.97 and 7.28 t C/ha in the state of West Bengal. This can be
was higher than Shorea
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168
A field experiment conducted by Mutanal et al., (2007) to assess the performance of
10 multipurpose tree species (viz., Casuarina equisetifolia, Eucalyptus tereticornis,
Grevillea robusta, Tectona grandis, Dalbergia sissoo, Anogeissus latifolia, Albizia
lebbek, Hardwickia binata, Azadirachta indica and Acacia nilotica) suitable for
agroforestry system in degraded gravelly soils at Main Agricultural Research Station,
University of Agricultural Sciences, Dharwad during the year 1990. At the end of
tenth year they found that height was significantly higher in C.equisetifolia followed
by E.tereticornis as compared to rest of tree species tried. Diameter of breast height
was higher in E.tereticornis as compared to other tree species. Biomass was
significantly higher in C.equisetifolia (109.18 kg/tree) followed by E.tereticornis
(108.5 kg/tree) and lowest in A.indica (7.54 kg/tree) followed by D.sissoo (12.69
kg/tree).
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169
Conclusion
The carbon sequestration capacity of a tree species depends upon its age, height,
girth size, biomass accumulation capacity, canopy diameter and most important
wood specific density. The carbon stock determined for various tree species shows
that trees like Terminalia chebula Retz, Pithecellobium dulce (Roxb) Bth, Limonia
acidissima L, Ficus benghalensis L, Tamarindus indica L, Morus alba L, Ailanthus
excelsa Roxb, Syzygium cumini (L) Skeel, Azadirachta indica A Juss, F. religiosa L,
Albizia lebbeck (L) Bth, Terminalia arjuna (Roxb) W & A, Eucalyptus globulus
Labill, Mangifera indica L and Casuarina equisetifolia L have the maximum carbon
sequestration capability.
So, the trees to be chosen for sequestering maximum amount of carbon in the
scenario of climate change, should be chosen with properties of highest specific
density, they should be fast growing, increasing biomass at a fast rate, should have a
huge canopy and also should have a better climate adaptability, richer litter
productivity, shorter rotation and should be disease resistant.