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Barbosa,O., J. A. Tratalos, P. R. Armsworth, R. G. Davies, R. A. Fuller, P. Johnson dan K. J. Gaston. 2007. Who
benefits from access to green space? A case study from Sheffield, UK. Landscape and Urban Planning, 83:
187–195.
Green spaces play a crucial role in supporting urban ecological and social systems, a
fact recognised in public policy commitments in both the UK and Europe. The amount
of provision, the distribution of green space and the ease of access to such spaces are
key contributors to social and ecological function in urban environments. We
measured distance along the transport network to public green space available to
households in Sheffield, and compared this with the distribution of private garden
space. In addition, we used a geodemographic database, Mosaic UK, to examine how
access to green space varies across different sectors of society. Public green spaces are
chronically underprovided relative to recommended targets. For example, 64% of
Sheffield households fail to meet the recommendation of the regulatory agency
English Nature (EN), that people should live no further than 300m from their nearest
green space. Moreover, this figure rises to 72% if we restrict attention to municipal
parks recognised by the local council. There is an overall reduction in coverage by
green space when moving from neighbourhoods where green space is primarily
publicly provided to those where it is privately provided. While access to public green
space varies significantly across different social groups, those enjoying the greatest
access include more deprived groups and older people.
Nowak,D.J. dan D. E. Crane. 2002. Carbon storage and sequestration by urban trees in the USA.
Environmental Pollution, 116:381–389.
Based on field data from 10 USA cities and national urban tree cover data, it is estimated that
urban trees in the coterminous USA currently store 700 million tonnes of carbon ($14,300
million value) with a gross carbon sequestration rate of 22.8 million tC/yr ($460 million/year)
(Nowak dan Crane, 2002). Carbon storage within cities ranges from 1.2 million tC in New York,
NY, to 19,300 tC in Jersey City, NJ. Regions with the greatest proportion of urban land are the
Northeast (8.5%) and the southeast (7.1%). Urban forests in the north central, northeast, south
central and southeast regions of the USA store and sequester the most carbon, with average
carbon storage per hectare greatest in southeast, north central, northeast and Pacific northwest
regions, respectively. The national average urban forest carbon storage density is 25.1 tC/ha,
compared with 53.5 tC/ha in forest stands (Nowak dan Crane, 2002). These data can be used to
help assess the actual and potential role of urban forests in reducing atmospheric carbon
dioxide, a dominant greenhouse gas.
.
Increasing levels of atmospheric carbon dioxide (CO2) and other ‘‘greenhouse’’ gases
[i.e. methane (CH4), chlorofluorocarbons, nitrous oxide (N2O), and troposphericozone
(O3)] are thought by many to be contributing to an increase in atmospheric
temperatures by the trapping of certain wavelengths of radiation in the atmosphere.
Some chemicals though, may be reducing atmospherictempe ratures (e.g. sulfur
dioxide, particulate matter, stratospheric ozone (Graedel and Crutzen, 1989; Hamburg
et al., 1997).
1. Graedel, T.E., Crutzen, P.J., 1989. The changing atmosphere. ScientificAmerican 261 (3), 58–68.
2. Hamburg, S.P., Harris, N., Jaeger, J., Karl, T.R., McFarland, M., Mitchell, J.F.B., Oppenheimer, M., Santer,
S., Schneider, S., Trenberth, K.E., Wigley, T.M.L., 1997. Common questions about climate change. United
Nation Environment Programme, World Meteorology Organization.
.
Globally averaged air temperature at the Earth’s surface has increased between 0.3
and 0.6 C since the late 1800s. A current estimate of the expected rise in average
surface air temperature globally is between 1 and 3.5 C by the year 2100 (Hamburg et
al., 1997).
1.
Hamburg, S.P., Harris, N., Jaeger, J., Karl, T.R., McFarland, M., Mitchell, J.F.B., Oppenheimer,
M., Santer, S., Schneider, S., Trenberth, K.E., Wigley, T.M.L., 1997. Common questions about
climate change. United Nation Environment Programme, World Meteorology Organization.
.
As urban areas already exhibit climatic differences compared with rural environments,
due in part to multiple artificial surfaces and high levels of fossil fuel combustion,
climate change impacts may be exacerbated in these areas (Nowak, 2000).
1. Nowak, D.J., 2000. The interactions between urban forests and global climate change. In: Abdollahi,
K.K., Ning, Z.H., Appeaning, A. (Eds.), Global Climate Change and the Urban Forest. GCRCC and Franklin
Press, Baton Rouge, LA, pp. 31–44.
.
Carbon dioxide is a dominant greenhouse gas. Increased atmosphericCO 2 is
attributable mostly to fossil fuel combustion (about 80–85%) and deforestation
worldwide (Schneider, 1989; Hamburg et al., 1997). Atmospheric carbon is estimated
to be increasing by approximately 2600 million metrictons annually (Sedjo, 1989).
1. Hamburg, S.P., N.Harris, J.Jaeger, T.R.Karl, M.McFarland, J.F.B.Mitchell, M.Oppenheimer, S.Santer,
S.Schneider, K.E.Trenberth dan T.M.L.Wigley. 1997. Common questions about climate change. United
Nation Environment Programme, World Meteorology Organization.
2. Schneider, S.H., 1989. The changing climate. Scientific American 261 (3), 70–79.
3. Sedjo, R.A., 1989. Forests to offset the greenhouse effect. J. Forestry 87, 12–15.
.
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
(e.g. management) can further affect CO2 source/sink dynamics of forests through
such factors as fossil fuel emissions and harvesting/utilization of biomass. However,
increasing the number of trees might potentially slow the accumulation of
atmospheric carbon (Moulton and Richards, 1990).
1. Moulton, R.J. dan K.R. Richards. 1990. Costs of Sequestering Carbon Through Tree Planting
and Forest Management in the United States. USDA Forest Service, General Technical Report
WO-58, Washington, DC.
.
Urban areas in the lower 48 United States have doubled in area between 1969 and
1994, and currently occupy 3.5% of the land base with an average tree cover of 27.1%
(Dwyer et al., 2000; Nowak et al., 2001b). Though urban areas continue to expand, and
urban forests play a significant role in environmental quality and human health,
relatively little is known about this resource. As urban forests both sequester CO2, and
affect the emission of CO2 from urban areas, urban forests can play a critical role in
helping combat increasing levels of atmospheric carbon dioxide.
1. Nowak, D.J., Noble, M.H., Sisinni, S.M. dan J.F.Dwyer. 2001b. Assessing the US urban forest resource. J.
Forestry, 99 (3): 37–42.
2. Dwyer, J.F., D.J.Nowak, M.H.Noble dan S.M. Sisinni. 2000. Connecting People with Ecosystems in the 21st
Century: An Assessment of our Nation’s Urban Forests (General Technical Report PNWGTR- 490). US
Department of Agriculture, Forest Service, Pacific Northwest Research Station, Portland, OR.
.
The first estimate of national carbon storage by urban trees (between 350 and 750
million tonnes; Nowak, 1993a) was based on an extrapolation of carbon data from one
city (Oakland, CA) and tree cover data from various USA cities (Nowak et al., 1996). A
later assessment, which included data from a second city (Chicago, IL), estimated
national carbon storage by urban trees at between 600 and 900 million tonnes
(Nowak, 1994).
1. Nowak, D.J., 1993a. Atmospheric carbon reduction by urban trees. J. Environ. Manage. 37
(3), 207–217.
2. Nowak, D.J., 1994. Atmospheric carbon dioxide reduction by Chicago’s urban forest. In:
McPherson, E.G., Nowak, D.J., Rowntree, R.A. (Eds.), Chicago’s Urban Forest Ecosystem:
Results of the Chicago Urban Forest Climate Project. USDA Forest Service General Technical
Report NE-186, Radnor, PA, pp. 83–94.
3. Nowak, D.J., R.A.Rowntree, E.G.McPherson, S.M. Sisinni, E. Kerkmann dan J.C. Stevens. 1996.
Measuring and analyzing urban tree cover. Lands. Urban Plann. 36, 49–57.
Brack, C.L. 2002. Pollution mitigation and carbon sequestration by an urban forest.
Environmental Pollution, 116: 195–200.
At the beginning of the 1900s, the Canberra plain was largely treeless. Graziers had carried out
extensive clearing of the original trees since the 1820s leaving only scattered remnants and
some plantings near homesteads. With the selection of Canberra as the site for the new capital
of Australia, extensive tree plantings began in 1911. These trees have delivered a number of
benefits, including aesthetic values and the amelioration of climatic extremes. Recently,
however, it was considered that the benefits might extend to pollution mitigation and the
sequestration of carbon. Brack (2002) outlined a case study of the value of the Canberra urban
forest with particular reference to pollution mitigation. This study uses a tree inventory,
modelling and decision support system developed to collect and use data about trees for tree
asset management. The decision support system (DISMUT) was developed to assist in the
management of about 400,000 trees planted in Canberra. The size of trees during the 5-year
Kyoto Commitment Period was estimated using DISMUT and multiplied by estimates of value
per square meter of canopy derived from available literature. The planted trees are estimated to
have a combined energy reduction, pollution mitigation and carbon sequestration value of
US$20–67 million during the period 2008–2012.
. Small, A.T. dan C.I. Czimczik. 2010. Carbon sequestration and greenhouse gas emissions in
urban turf. Geophysical Research Letters, 37 (2): ….
Undisturbed grasslands can sequester significant quantities of organic carbon (OC) in
soils. Irrigation and fertilization enhance CO2 sequestration in managed turfgrass
ecosystems but can also increase emissions of CO2 and other greenhouse gases
(GHGs). To better understand the GHG balance of urban turf, Small dan Czimczik
(2010) measured OC sequestration rates and emission of N2O (a GHG ∼ 300 times
more effective than CO2) in Southern California, USA. It is also estimated CO2
emissions generated by fuel combustion, fertilizer production, and irrigation. We show
that turf emits significant quantities of N2O (0.1–0.3 g N m−2 yr−1) associated with
frequent fertilization. In ornamental lawns this is offset by OC sequestration (140 g C
m−2 yr−1), while in athletic fields, there is no OC sequestration because of frequent
surface restoration. Large indirect emissions of CO2 associated with turfgrass
management make it clear that OC sequestration by turfgrass cannot mitigate GHG
emissions in cities.
Novak, D.J., J.C.Stevens, S.M.Sisinni dan C.J.Luley. 2002. Effects of Urban Tree
Management and Species Selection on Atmospheric Carbon Dioxide. Journal of
Arboriculture, 28(3): 113-122.
Trees sequester and store carbon in their tissue at differing rates and amounts based
on such factors as tree size at maturity, life span, and growth rate. Concurrently, tree
care practices release carbon back to the atmosphere based on fossil-fuel emissions
from maintenance equipment (e.g., chain saws, trucks, chippers) (Novak et al.,
2002). Management choices such as tree locations for energy conservation and tree
disposal methods after removal also affect the net carbon effect of the urban forest.
Different species, decomposition, energy conservation, and maintenance scenarios
were evaluated to determine how these factors influence the net carbon impact of
urban forests and their management. If carbon (via fossil-fuel combustion) is used to
maintain vegetation structure and health, urban forest ecosystems eventually will
become net emitters of carbon unless secondary carbon reductions (e.g., energy
conservation) or limiting decomposition via long-term carbon storage (e.g., wood
products, landfills) can be accomplished to offset the maintenance carbon emissions.
Management practices to maximize the net benefits of urban forests on atmospheric
carbon dioxide are discussed.
Choudhari,N.R., D.M. Mahajan , V.R. Gunale dan M.G. Chaskar. 2014. Assessment of carbon
sequestration potential in an urban managed garden in the pimpri-chinchwad city . National
Conference: 10th & 11th January 2014. p.41-44.
Carbon storage and sequestration by urban Garden trees was calculated to assess the role of
urban forests in relation to climate change. In Pimpri-Chinchwad urban Gardens, as important
elements of urban residential environments, could have significant sustainability potential
(Choudhari et al., 2014).
The biomass of standing vegetation was estimated by using direct estimation methods after
measuring their diameter and height, Tree Vegetation carbon pool was largest in
In all sampled sites we noticed heterogeneous carbon pool.
Durga tekadi is major biodiversity hot spots in gardens zone, while this sites sequestrated
highest amount of carbon in their biomass was 289.83 tonnes in 30.00 hectare, whereas site
Mhatoba garden wakad has sequestrated the lowest amount of CO2 (13.75 tonnes) in total
1.81hectares, The total recorded biomass in the garden zone was 1419.85 tonnes and total
amount of sequestrated carbon was 681.53 tonnes in 47.12 hectares. Total number of individual
trees was 4975 in numbers (Choudhari et al., 2014). There were other recorded dominant
species are peltophorum pterocarpum (Dc.) Baker, Acacia longifolia Willd.; Pongamia
pinnata (L.) Pierre, Dalbergia latifolia Roxb.; Ficus benjamina L., Grevillea robusta Cunn.
Nowak, D.J., E.J. Greenfield, R.E. Hoehn dan E. Lapoint. 2013. Carbon storage and sequestration
by trees in urban and community areas of the United States. Environmental Pollution, 178 (…):
229-236.
Carbon storage and sequestration by urban trees in the United States was quantified
to assess the magnitude and role of urban forests in relation to climate change. Urban
tree field data from 28 cities and 6 states were used to determine the average carbon
density per unit of tree cover. These data were applied to statewide urban tree cover
measurements to determine total urban forest carbon storage and annual
sequestration by state and nationally. Urban whole tree carbon storage densities
average 7.69 kg C m2 of tree cover and sequestration densities average 0.28 kg C m2
of tree cover per year. Total tree carbon storage in U.S. urban areas (c. 2005) is
estimated at 643 million tonnes ($50.5 billion value; 95% CI ¼ 597 million and 690
million tonnes) and annual sequestration is estimated at 25.6 million tonnes ($2.0
billion value; 95% CI ¼ 23.7 million to 27.4 million tonnes).
.
Trees act as a sink for carbon dioxide (CO2) by fixing carbon during photosynthesis and
storing carbon as biomass. The net long-term CO2 source/sink dynamics of forests
change through time as trees grow, die, and decay. Human influences on forests (e.g.,
management) can further affect CO2 source/sink dynamics of forests through such
factors as fossil fuel emissions and harvesting/utilization of biomass (Nowak et al.,
2002). Trees in urban areas (i.e., urban forests) currently store carbon, which can be
emitted back to the atmosphere after tree death, and sequester carbon as they grow.
Urban trees also influence air temperatures and building energy use, and
consequently alter carbon emissions from numerous urban sources (e.g., power
plants) (Nowak, 1993). Thus, urban trees influence local climate, carbon cycles, energy
use and climate change (Abdollahi et al., 2000; Gill et al., 2007; Lal and Augustine,
2012).
1. Abdollahi, K.K., Z.H.Ning dan A.Appeaning. 2000. Global Climate Change and the Urban Forest. GCRCC
and Franklin Press, Baton Rouge, pp. 31-44.
2. Gill, S.E., J.F.Handley, A.R.Ennos dan S. Pauleit. 2007. Adapting cities for climate change: the role of the
green infrastructure. Built Environment, 33 (1): 115-133.
3. Lal, R. dan B.Augustine. 2012. Carbon Sequestration in Urban Ecosystems. Springer, New York, p. 385.
4. Nowak, D.J., J.C.Stevens, S.M.Sisinni dan C.J. Luley. 2002. Effects of urban tree management and species
selection on atmospheric carbon dioxide. Journal of Arboriculture, 28 (3): 113-122.
.
Carbon storage
As part of the carbon cycle, trees transform carbon dioxide to biomass through
photosynthesis (Liu dan Li, 2012). This function is beneficial to humans because it
counteracts emissions of carbon dioxide (CO2), a greenhouse gas. Anthropogenic
carbon emissions have caused a 40% increase in atmospheric CO2 concentrations in
the last century, a change which is known to be causing global warming (IPCC, 2013).
IPCC. 2013. Climate Change 2013: The Physical Science Basis. (Assessment Report No.
AR5). World Meteorological Organisation and United Nations Environment Program.
.
Allometric Equations
Tree carbon storage can be quantified with allometric equations which relate tree
dimensions to tree volume or biomass (Henry et al., 2011; Picard, Saint-André, &
Henry, 2012). Initially developed for sustainable management of forest resources,
allometric equations are now in demand for global carbon cycle studies of forest
carbon storage and carbon emission reduction schemes (Henry et al., 2011).
1. Henry, M., N.Picard, C.Trotta, R.J.Manlay , R.Valentini, M.Bernoux dan L. S. André. 2011.
Estimating Tree Biomass of Sub-Saharan African Forests: a Review of Available Allometric
Equations. Silva Fennica, 45(3B), 477-569.
2. Picard, N., L.S.André dan M.Henry. 2012. Manual for building tree volume and biomass
allometric equations: from field measurement to prediction. (Manual). Montpellier, France:
Food and Agricultural Organisation of the United Nations (FAO); Centre de Coopération
Internationale en Recherche Agronomique pour le Dévelopment (CIRAD).
.
A species allometric equation is developed through the destructive analysis of multiple
trees of the same species. Tree dimensions such as height and diameter at breast
height (DBH) are measured and the tree is cut up and divided into sections (stem,
branches, foliage and roots) for weighing to determine its biomass (Beets et al., 2012;
McHale et al., 2009; Picard, Saint-André, & Henry, 2012). Using linear regression, a
relationship between tree dimensions and tree volume, biomass or carbon content
can be derived – this is an allometric equation.
1. Beets, P. N., M.O.Kimberley, G.R.Oliver, S.H.Pearce, J.D.Graham dan A.Brandon. 2012.
Allometric Equations for Estimating Carbon Stocks in Natural Forest in New Zealand. Forests,
3: 818-839.
2. McHale, M.R., I.C.Burke, M.A.Lefsky, P.J.Peper dan E.G. McPherson. 2009. Urban forest
biomass estimates: is it important to use allometric relationships developed specifically for
urban trees?. Urban Ecosystems, 12: 95-113.
3. Picard, N., L.S.André dan M.Henry. 2012. Manual for building tree volume and biomass
allometric equations: from field measurement to prediction. (Manual). Montpellier, France:
Food and Agricultural Organisation of the United Nations (FAO); Centre de Coopération
Internationale en Recherche Agronomique pour le Dévelopment (CIRAD).
.
The development process is time-consuming, thus sample sizes are usually small and
lead to a limited range of DBH values for which an equation is valid (Picard, André dan
Henry, 2012). Composite equations, which combine equations with valid DBH ranges,
are commonly used for carbon storage calculations (Nowak dan Crane, 2002a). The
customary power form of an allometric equation is Y = aXb : above-ground tree
volume, biomass or carbon content, Y, is related to the DBH measurement or a DBH2Height composite, X, (Beets et al., 2012; Picard, André dan Henry, 2012).
1. Beets, P. N., M.O.Kimberley, G.R.Oliver, Pearce, S. H., Graham, J. D. dan A. Brandon. 2012. Allometric
Equations for Estimating Carbon Stocks in Natural Forest in New Zealand. Forests, 3: 818-839.
2. Nowak, D. J. dan D.E.Crane. 2002a. Carbon storage and sequestration by urban trees in the USA.
Environmental Pollution, 116(3): 381-389.
3. Picard, N., L.S.André dan M. Henry. 2012. Manual for building tree volume and biomass allometric
equations: from field measurement to prediction. (Manual). Montpellier, France: Food and Agricultural
Organisation of the United Nations (FAO); Centre de Coopération Internationale en Recherche
Agronomique pour le Dévelopment (CIRAD).
.
New Zealand Allometric Equations
Recent research in NZ has developed allometric equations for native forest species,
from trees in natural forests and in urban environments. Beets et al. (2012) developed
allometric relationships for 15 native hardwood species and a mixed-species equation
from destructive analysis of trees from natural forests around NZ following thinning
operations or windfall.
Beets, P. N., M.O.Kimberley, G.R.Oliver, S.H.Pearce, J.D.Graham dan A.Brandon. 2012.
Allometric Equations for Estimating Carbon Stocks in Natural Forest in New Zealand.
Forests, 3: 818-839.
.
i-Tree Eco
The US Forest Service, developed the Urban Forest Effects Model (UFORE) in the late
1990s which was adapted and rebranded as i-Tree Eco in 2006 (i-Tree, 2013a). i-Tree
Eco is a comprehensive model that uses environmental data to quantify urban forest
structure and a range of forest effects, or ecosystem services (i-Tree, 2013a). The
model consists of several back-end databases: field tree data, species information,
meteorological data, pollution data and pollutant valuation rates (i-Tree, 2013b).
Collectively, these databases can quantify air pollution removal, carbon storage and
sequestration, rainfall interception and the dollar valuation of these ecosystem
services for a sample of urban trees (Nowak et al., 2008a; Nowak, Crane dan Stevens,
2006).
1. i-Tree. 2013a. i-Tree Eco. Retrieved from http://www.itreetools.org/eco/
2. Nowak, D. J., D.E.Crane, J.C.Stevens, R.E. Hoehn, J.T. Walton dan J.Bond. 2008a. A groundbased method of assessing urban forest structure and ecosystem services. Arboriculture and
Urban Forestry, 34(2), 347-358.
3. Nowak, D. J., D.E.Crane dan J.C.Stevens. 2006. Air pollution removal by urban trees and
shrubs in the United States. Urban Forestry & Urban Greening, 4: 115-123.
.
i-Tree Eco carbon quantification
i-Tree Eco uses forest-derived allometric equations to estimate carbon storage for
urban trees (Nowak dan Crane, 2002a). i-Tree Eco assessments use species allometric
equations where possible or, where a species equation is not available, a genusrelative equation, or an average of hardwood or conifer equations are applied (Nowak
et al., 2002b). There were no NZ native species allometric equations in the i-Tree Eco
species database so the average hardwood equation was used. Its formula is not
shown here because it is a complex equation that incorporates the carbon storage
outputs from numerous hardwood allometric equations in the literature to find an
average.
For accurate carbon estimates, species-specific allometric equations are favoured over
generalised mixed-species equations (Henry et al., 2011). However, considering the
process required to develop allometric equations, striving for this level of accuracy is
not always practicable.
1. Henry, M., Picard, N., Trotta, C., Manlay, R. J., Valentini, R., M.Bernoux dan L.S. André. 2011. Estimating
Tree Biomass of Sub-Saharan African Forests: a Review of Available Allometric Equations. Silva Fennica,
45(3B: 477-569.
2. Nowak, D. J. dan D.E.Crane . 2002a. Carbon storage and sequestration by urban trees in the USA.
Environmental Pollution, 116(3): 381-389.
3. Nowak, D. J., D.E.Crane, J.C. Stevens dan M. Ibarra. 2002b. Brooklyn's Urban Forest. ( No. NE-290).
Northeastern Research Station: United States Department of Agriculture, Forest Service.
Brack C.L. 2002. Pollution mitigation and carbon sequestration by an urban forest.
Environmental Pollution , 116 (1):195-200.
At the beginning of the 1900s, the Canberra plain was largely treeless. Graziers had
carried out extensive clearing of the original trees since the 1820s leaving only
scattered remnants and some plantings near homesteads. With the selection of
Canberra as the site for the new capital of Australia, extensive tree plantings began in
1911. These trees have delivered a number of benefits, including aesthetic values and
the amelioration of climatic extremes. Recently, however, it was considered that the
benefits might extend to pollution mitigation and the sequestration of carbon. This
paper outlines a case study of the value of the Canberra urban forest with particular
reference to pollution mitigation. This study uses a tree inventory, modelling and
decision support system developed to collect and use data about trees for tree asset
management. The decision support system (DISMUT) was developed to assist in the
management of about 400,000 trees planted in Canberra. The size of trees during the
5-year Kyoto Commitment Period was estimated using DISMUT and multiplied by
estimates of value per square meter of canopy derived from available literature. The
planted trees are estimated to have a combined energy reduction, pollution mitigation
and carbon sequestration value of US$20-67 million during the period 2008-2012.
. Munishi,P.K., M. Mhagama, R. Muheto dan S.M. Andrew. 2008. The Role Of Urban Forestry In
Mitigating Climate Change And Performing Environmental Services In Tanzania. Tanzania
Journal of Forestry and Nature Conservation, 77 : 25-34.
The possibility of global climate change, due to increasing levels of CO2 concentrations is one of the key
environmental concerns today, and the role of terrestrial vegetation management has received attention as
a means of mitigating carbon emissions and climate change. Munishi et al. (2008) studied tree dimensions
and assessment of plant species composition were used to quantify the potential of urban ecosystems in
acting as carbon sink and mitigating climate change through carbon assimilation and storage and the
potential of the system to enhance biodiversity conservation taking Morogoro Municipality as a case study.
Biomass/carbon models for trees were developed and used to predict biomass/carbon storage based on tree
diameters. The model was in the form B = 0.5927DBH1.8316 (r2 =0.91, P< 0.01). The carbon content was
computed as 50% of the tree biomass. The tree carbon for Morogoro municipality ranged from 4.63±3.39 to
21.18±12.41t km-1 length of ground surface along roads and avenues. Newly established areas seemed to
have lower carbon storage potential while areas established earlier have highest carbon storage potential.
About 36 different tree species growing/planted in the Morogoro municipal were identified, dominated by
Senna siamea, Azadirachta indica, Polyalthia longifolia, Leucaena leucocephala, Pithecelobium dulce and
Mangifera indica. Apart from being natural amenity the tree species also act as CO2 sink through
photosynthesis and areas of ex-situ conservation of plant diversity.
Urban forestry can store large amount of carbon in addition to biodiversity conservation especially where
they cover extensive areas like parks, gardens and avenues managed over long periods, as is the case in
urban ecosystems. Improved management of urban forests will likely improve the potential for carbon
storage by terrestrial vegetation as a means of mitigating CO2 emissions and climate change as well as
biodiversity conservation (Munishi et al. , 2008) .
Russo, A., F.J. Escobedo, N. Timilsina, A.O. Schmitt, S. Varela dan S. Zerbe. 2014. Assessing urban
tree carbon storage and sequestration in Bolzano, Italy. International Journal of Biodiversity
Science, Ecosystem Services & Management , 10 (1): 54-70.
Recent climate change, environmental design, and ecological conservation policies require new
and existing urban developments to mitigate and offset carbon dioxide emissions and for cities
to become carbon neutral. Some North American models and tools are available and can be
used to quantify the carbon offset function of urban trees. But, little information on urban tree
carbon storage and sequestration exists from the European Southern Alps. Also, the use of these
North American models in Europe has never been assessed. Russo et al. (2014) developed a
protocol to quantify aboveground carbon (C) storage and sequestration using a subsample of
urban trees in Bolzano, Italy, and assessed two existing and available C estimation models.
Carbon storage and sequestration were estimated using city-specific dendrometrics and
allometric biomass equations primarily from Europe and two other United States models; the
UFORE (Urban Forest Effects Model) and the CUFR Tree Carbon Calculator (CTCC). The UFORE
model carbon storage estimates were the lowest while the CUFR Tree Carbon Calculator (CTCC)
C sequestration estimates were the highest. Results from this study can be used to plan, design,
and manage urban forests in northern Italy to maximize C offset potential, provide ecosystem
services, and for developing carbon neutral policies.
Ahmedin, A.M., S. Bam, K.T.Siraj dan A.J.S. Raju . 2013.Assessment of biomass and carbon
sequestration potentials of standing Pongamia pinnata in Andhra University, Visakhapatnam,
India. Bioscience Discovery, 4(2): 143-148 .
The significance of forested areas in carbon sequestration is conventional, and well
renowned. But, hardly any attempts have been made to study the potential of trees in
carbon sequestration from urban areas. Andhra University was selected for the study
in Visakhapatnam city with the objectives of quantifying the total carbon
sequestration by Pongamia pinata. Stratified random sampling was used for assessing
biomass in two site and about 230 P. pinnata trees were taken. Biomass was calculated
using Non-destructive allometric models. The biomass carbon content was taken as
55% of the tree biomass. Soil samples were taken from soil profile up to 40 cm depth
for deep soils and up to bedrock for shallow soils at an interval of 10 and 20 cm for top
and sub-soil respectively. Walkley Black Wet Oxidation method was applied for
measuring soil organic carbon. Belowground biomass was estimated by the Root:Shoot
ratio relationship. Total biomass and soil carbon was higher in Site-2 than in Site-1.
Total carbon sequestration in Site-2 was found 1.59 times higher compared to Site-1
but the mean SOC stored was found higher in Site-1 than in Site-2, i.e.,14.48 tC/ha and
10.33 tC/ha, respectively (Ahmedin et al., 2013).
Biomass Estimation of the Tree
The biomass was estimated from allometric relations between the tree diameter at DBH and
tree biomass (Mikaelian et al., 1997). For the estimation of aboveground biomass, the model
developed by Brown et al (1989) has been used. The equation used for estimation of biomass
was:
Y = Exp. {-2.4090 + 0.9522 In (D2 x H x S)}
Where; Exp. {....} means the “raised to the power of {....}”. Y is the above ground biomass (kg), H
is the height of the trees (meter), D is the diameter at breast height in cm, and S is the wood
density (gm/cm3).The specific gravity of P. pinnata tree was taken as 0.609 (Rajput et al., 1985).
Below ground biomass was estimated 20% of the aboveground biomass (Cairns et al., 1997;
Mokany et al., 2006) and 15% of aboveground biomass was considered for litter biomass
estimation (Achard et al., 2002).
1. Achard, F., H.D.Eva , H.J.Stibig , P.Mayaux , J. Gallego , T. Richards dan J.P. Malingreau. 2002.
Determination of deforestation rates of the world’s human tropical forests. Science, 297: 999–1002.
2. Brown, S., A.J.R.Gillespie dan A.E.Lugo. 1989. Biomass estimation methods for tropical forests with
applications to forest inventory data. Forest Science, 35:881- 902.
3. Rajput,S.S., N.K.Shukla dan V.K. Gupta. 1985. Specific gravity of Indian timbers. Journal of Timber
Development Association of India, XXXI(3): 12-41.
4. Cairns, M.A., S.Brown , E.H.Helmer dan G.A.Baumgardner. 1997. Root biomass allocation in the world’s
upland forests . Forest Science, 111: 1–11.
5. Mokany,K., J.R.Raison dan A.S.Prokushkin. 2006. Critical analysis of root-shoot rations in terrestrial
biomes Glob. Change Biol.12 84–96.
6. Mikaelian,T.M.T. dan M.D.Korzukhin. 1997. Biomass equations for sixty-five North American tree species.
Forest Ecology and Management, 97:1-24.
Alison,W. 2012. Potential Urban Forest Carbon Sequestration and Storage Capacities in Burnside
Industrial Park, Nova Scotia. MES Thesis , School of Resource & Environmental Studies
Urban and industrial settings represent potential areas for increased carbon (C)
sequestration and storage through intensified tree growth. Consisting of an estimated
1270 ha of land once entirely forested, Burnside Industrial Park (BIP) in Dartmouth,
Nova Scotia. Alison (2012) examined degree to which intensified urban tree planting
within the BIP ecosystem could enhance C sequestration and storage. This was
achieved by conducting a geospatial analysis in combination with construction of a C
model. Three scenarios urban forest development were examined. If all potential
planting spots are filled with trees by 2020, an estimated 26,368 tC, at a sequestration
rate of 635 tC/yr, could be achieved by 2050. Next, we explored the challenges and
opportunities associated with pursuing C offset markets as a means for funding urban
forest development within BIP.
. Velasco,E., M. Roth, S.H. Tan, M. Quak, S.D.A. Nabarro dan L. Norford. 2013. The role of
vegetation in the CO2 flux from a tropical urban neighbourhood. Atmos. Chem. Phys. Discuss.,
13: 7267–7310.
Urban surfaces are usually net sources of CO2. Vegetation can potentially have an important role in reducing
the CO2 emitted by anthropogenic activities in cities, particularly when vegetation is extensive and/or
evergreen. Negative daytime CO2 fluxes, for example 5 have been observed during the growing season at
suburban sites characterized by abundant vegetation and low population density. A direct and accurate
estimation of carbon uptake by urban vegetation is difficult due to the particular characteristics of the urban
ecosystem and high variability in tree distribution and species.
Velasco et al. (2013) investigated the role of urban vegetation in the CO2 flux from a residential
neighbourhood in Singapore using two different approaches. CO2 fluxes measured directly by eddy
covariance are compared with emissions estimated from emissions factors and activity data. The latter
includes contributions from vehicular traffic, household combustion, soil respiration and human breathing.
The difference between estimated emissions and measured fluxes should approximate the biogenic flux. In
addition, a tree survey was conducted to estimate the annual CO2 sequestration using allometric equations
and an alternative model of the metabolic theory of ecology for tropical forests. Palm trees, banana plants
and turfgrass were also included in the survey with their annual CO2 uptake obtained from published growth
rates. Both approaches agree within 2% and suggest that vegetation captures 8% of the total emitted CO2 in
the residential neighbourhood studied. A net uptake of 1.4 ton km−2 day−1 (510 ton km−2 yr−1) was
estimated from the difference between the daily CO2 uptake by photosynthesis (3.95 tonkm−2) and release
by respiration (2.55 ton km−2). The study shows the importance of urban vegetation at the local scale for
climate change mitigation in the tropics.
.
Dry biomass and CO2 storage estimation for woody trees
CO2 storage refers to the accumulation of biomass as trees grow over time. The
amount of CO2 stored by an urban tree is proportional to its dry biomass and
influenced by management practices (McPherson, 1994). The common method to
estimate dry biomass is by allometric equations based on parameters such as GBH,
tree height, wood specific density (WSD), tree age and condition, and forest type. The
methodology 20 to convert dry biomass into stored CO2 is well established (Aguaron
and McPherson, 2012).
1. Aguaron, E. dan G. McPherson. 2012. Comparison of methods for estimating carbon dioxide
storage by Sacramento’s urban forest, in: Carbon Sequestration in Urban Ecosystems, edited
by: Lal, R. and Augustin, B., Springer.
2. McPherson, E. G. 1994. Using urban forests for energy efficiency and carbon storage. J.
Forest., 92: 36–41.
. Velasco, E., M. Roth, S.H. Tan, M. Quak, S.D.A. Nabarro dan L. Norford. 2013. The role of
vegetation in the CO2 flux from a tropical urban neighbourhood. Atmos. Chem. Phys. Discuss.,
13: 7267–7310.
Velasco et al. (2013) showed that vegetation in residential areas of tropical cities can offset a
significant fraction of the anthropogenic CO2 flux emitted within a specific neighbourhood
depending on the intensity of the local anthropogenic emission sources and biomass
characteristics. The CO2 sequestered by vegetation in the present study, however, cannot be
extrapolated to the whole city. Although results are only valid for the particular neighbourhood
investigated, they provide valuable information on the importance of urban vegetation for
climate change mitigation strategies. For example, the data demonstrate the importance of
large trees for GHG management. Tree planting programs should also consider the growth rate
and potential carbon uptake when selecting type and species. Priority must be given to woody
trees over palms and ornamental plants which sometimes are preferred for aesthetic reasons.
Similarly, large trees should not be replaced by young trees and palms, as it is the tendency
along secondary roads in Singapore.
. The role of vegetation in the CO2 flux from a tropical urban neighbourhood. Atmos. Chem.
Phys. Discuss., 13, 7267–7310.
E. Velasco1, M. Roth2, S. H. Tan2, M. Quak2, S. D. A. Nabarro3, and L. Norford. 2013.
The influence of vegetation on the urban CO2 flux may be even higher if the indirect effects
from local cooling through shading and transpiration are included. Local cooling results in lower
demand for air conditioning, which can reduce the emission of GHG if the energy used to run
the cooling devices is obtained from fossil fuel sources (Akbari, 2002).
A complete assessment of the benefits and costs of urban vegetation needs to consider all
environmental, economic, social and cultural aspects as suggested by Pataki et al. (2011). Here,
we have quantified the reduction in the net CO2 flux by vegetation considering only emissions
due to activities occurring within the boundaries of the study domain. External emissions arising
from local activities, such as electricity generation, are not considered.
1. Akbari, H. 2002. Shade trees reduce building energy use and CO2 emissions from power plants, Environ.
Pollut., 116:119–126.
2. Pataki, D. E., M.M.Carreiro, J. Cherrier, N.E. Grulke, V. Jennings, S. Pincetl, R.V. Pouyat, T.H. Whitlow dan
W.C.Zipperer. 2011. Coupling biogeochemical cycles in urban environments: ecosystem services, green
solutions, and misconceptions, Front. Ecol. Environ., 9: 27–36.
. The role of vegetation in the CO2 flux from a tropical urban neighbourhood. Atmos. Chem.
Phys. Discuss., 13, 7267–7310.
E. Velasco1, M. Roth2, S. H. Tan2, M. Quak2, S. D. A. Nabarro3, and L. Norford. 2013.
Singapore has a national per capita emission of 6.8 ton CO2 yr−1 (Velasco and Roth, 2012). When limiting
emissions to the Telok Kurau neighbourhood and considering only emissions from combustion sources (i.e.
vehicular traffic and households) as is usually the case for emissions inventories at the city scale, per capita
emission is only 688 kg yr−1. This suggests that the majority of Singapore’s GHG emissions have their origin
outside residential areas. This is consistent with the local emissions inventory, which shows that 81% of the
CO2 emissions come from industry and electricity generation (Ministry of the Environment and Water
Resources, 2008) which are concentrated in industrial parks. Considering all CO2 sources and sinks within
the study region, the per capita CO2 emission is 874 kg yr−1 (human breathing and soil respiration add 147
and 107 kg person−1 yr−1, respectively, but vegetation absorbs 68 kg person−1 yr−1).
This value can be compared with the per capita emission of 16 ton yr−1 associated with
the production of all consumed goods, including those produced overseas, (Schulz, 2010). The present
vegetation in Telok Kurau therefore reduces the carbon footprint of the residents living in this low-rise
residential neighbourhood of Singapore by only 0.4 %.
1. Schulz, N. B. 2010. Delving into the carbon footprints of Singapore – comparing direct and indirect
greenhouse gas emissions of a small and open economic system. Energy Policy, 38: 4848– 4855.
2. Velasco, E. dan M. Roth. 2012. Review of Singapore’s air quality and greenhouse gas emissions: current
situation and opportunities. Jour. Air Waste Manage. Assoc., 62: 625–641.
. McPherson, E. G. dan J.R.Simpson. 1999. Carbon dioxide reduction through urban
forestry: Guidelines for professional and volunteer tree planters. Gen. Tech. Rep. PSWGTR171. Albany, CA: Pacific Southwest Research Station, Forest Service, U.S. Department
of Agriculture; 237 p.
Carbon dioxide reduction through urban forestry as a tool for utilities, urban foresters
and arborists, municipalities, consultants, non-profit organizations and others to
determine the effects of urban forests on atmospheric carbon dioxide (CO2) reduction.
The calculation of CO2 reduction that can be made with the use of these Guidelines
enables decision makers to incorporate urban forestry into their efforts to protect our
global climate. McPherson dan Simpson (1999) reported current and future CO2
reductions through a standardized accounting process; evaluate the cost-effectiveness
of urban forestry programs with CO2 reduction measures; compare benefits and costs
of alternative urban forestry program designs; and produce educational materials that
assess potential CO2 reduction benefits and provide information on tree selection,
placement, planting, and stewardship.
Harmon, E.H., W.K.Ferrell dan J.F.Franklin. 1990. Effects on carbon storage of conversion of old
growth forests to young forests. Science, 297: 699-702.
Carbon Dioxide Sequestration
Sequestration depends on tree growth and mortality, which in turn depends on
species composition, age structure, and health of the forest. Newly planted forests
accumulate CO2 rapidly for several decades, and then the annual increase of
sequestered CO2 declines (Harmon et al., 1990). Old-growth forests can release as
much CO2 from the decay of dying trees as they sequester from new growth. When
trees are stressed, as during hot, dry weather, they can lose their normal ability to
absorb CO2. Trees close their pores as a defensive mechanism to avoid excess water
loss. Hence, healthy, vigorous, growing trees will absorb more CO2 than will trees that
are diseased or otherwise stressed.
.
Because of higher tree densities, rural forests sequester about twice as much CO2 as
urban forests per unit land area, between 4 to 8 t/ha on average (Birdsey 1992).
However, because urban trees tend to grow faster than rural trees, they sequester
more CO2 on a per-tree basis (Jo dan McPherson 1995). Data on radial trunk growth
were used to calculate annual sequestration for major genera in Chicago (Jo dan
McPherson, 1995; Nowak 1994). Sequestration can range from 16 kg/yr (35 lb/yr) for
small, slow-growing trees with 8- to 15-cm dbh (3-6 inches diameter at breast height)
to 360 kg/yr (800 lb) for larger trees growing at their maximum rate.
1. Birdsey, R. 1992. Carbon storage and accumulation in United States forest ecosystems. Gen.
Tech. Rep. WO-GTR-59. Radnor, PA: Northeastern Forest Experiment Station, Forest Service,
U.S. Department of Agriculture; 51 p.
2. Jo, H.K. dan E.G.McPherson. 1995. Carbon storage and flux in urban residential greenspace.
Journal of Environmental Management, 45: 109-133.
3. Nowak, D.J. 1994. Atmospheric carbon dioxide reduction by Chicago’s urban forest, chapter .
In: McPherson, E.G.; Nowak, D.J.; Rowntree, R.A., eds. Chicago’s urban forest ecosystem:
results of the Chicago urban forest climate project. Gen. Tech. Rep. NE-GTR-186. Radnor, PA:
Northeastern Forest Experiment Station, Forest Service, U.S. Department of Agriculture; 8394.
Nowak, D.J. dan D. E. Crane. 2002. Carbon Storage and Sequestration by Urban Trees in the
U.S.A. Environmental Pollution, 116: 381 – 389.
A very important function of trees and forests both in and out of urban areas is that by
sequestering carbon, C, they withhold an even larger amount of CO2 e (equivalent)
from the earth's atmosphere. At present, the body of credible climate research
identifies CO2 as a major green house gas that as it accumulates in the earth's
atmosphere contributes to global warming. Nowak dan Crane (2002) have estimated
that urban trees in the U.S. hold about 774 million tons of C, thus withholding 2.84
billion tons of CO2 from the atmosphere. The prevailing view is that this function is
performed by standing and live trees. While attention has been devoted to changes in
the level of sequestration as a function of changes in the size of the nation's urban
forests, no attention has been devoted to the sequestration consequences of what
becomes of the downed trees themselves.
Tagupa,C., A. Lopez, F. Caperida, G. Pamunag dan A. Luzada. 2010. CARBON DIOXIDE (CO2)
SEQUESTRATION CAPACITY OF TAMPILISAN FOREST. E-International Scientific Research Journal.
2(3): 182-191.
Tagupa et al. (2010) estimated the carbon dioxide sequestered and stored in the forest
trees of Jose Rizal Memorial State University – Tampilisan Campus reservation. This
site contained the trees species Mohagany (Swietenia macrophylla), Gmelina (Gmelina
arborea), Mangium (acacia magium) Rubber (Hevea brasilliensis) and natural forest
trees (e.g. Dipterocarp species, etc). Results revealed that standard size (sized trees
have better CO2 sequestration potential than the sapling and pole). These trees have
the biggest merchantable height, trunk diameter and wood density. Among the
species considered, Gmelina had the highest amount of CO2 sequestered and stored in
stem followed by Mangium, Rubber and Mahogany at standard size. In addition,
regression analysis indicated that the rate of CO2 sequestered and stored on trees are
related to the growth characteristics as trunk diameter (DBH) and total height, but not
with wood density. Moreover, the forest stand of JRMSU – Tampilisan Campus
reservation has a total sequestration capacity of 88.17 kT CO2 (Tagupa et al. , 2010) .
.
Forest trees are considered as an important factor in mitigating climate
change because of their role in carbon sequestration – the process of removing carbon
dioxide (CO2) from the atmosphere and ‘storing’ it in plants that use sunlight to turn
CO2 into biomass and oxygen (ACIAR, 2008).
1.
Cacho, O.J., R.L.Hean, R.M.Wise, O.Cacho, R.Hean, K.Ginoga, R.Wise, D. Djaenudin,
M.Lugina, Y. Wulan, B.Subarudi, M.van Noordwijk dan N.Khasanah. 2008.
Economic potential of land – used change and forestry for carbon sequestration
and poverty reduction. ACIAR technical reports No. 68, 98 pp.
Tagupa,C., A. Lopez dan F. Caperida, G. Pamunag dan A. Luzada. 2010. CARBON DIOXIDE (CO2)
SEQUESTRATION CAPACITY OF TAMPILISAN FOREST. E-International Scientific Research Journal.
ISSN: 2094-1749, 2(3): 182-191.
Carbon Dioxide Sequestration Capacity of Tampilisan Forest.
Tagupa et al. (2010) analyzed carbon dioxide (CO2) sequestration capacity of each of
the forest trees in the reservation of JRMSU – Tampilisan campus. Among the trees,
Rubber had sequestered the highest amount of CO2 at 56.41 kT, followed by the
natural forest trees, then Mahogany, Mangium and Gmelina at 27.91, 1.87, 1.51 and
0.47 kT, respectively. A total of 88.17 kT was observed to be the CO2 sequestration
capacity of the forest stand in the reservation area of JRMSU – Tampilisan campus. The
variation in the amount of CO2 sequestered and stored in the species within the forest
stand was affected greatly by the stand density of trees of their total population and
the area planted to these trees, aside from other their biomass. The wider the area
occupied by Rubber, compared to Mangium, Mahogany and Gmelina which covered
only 10, 20, and 10 hectares, respectively. Whereas, the natural forest trees were
about 200 hectares (Tagupa et al., 2010) .
Arneth, A., F. M. Kelliher, T.M. McSeveny dan J. N. Byers. 1998. Net ecosystem productivity, net
primary productivity and ecosystem carbon sequestration in a Pinus radiata plantation subject
to soil water deficit. Tree Physiol., 18 (12): 785-793 .
Tree carbon (C) uptake (net primary productivity excluding fine root turnover, NPP′) in a New Zealand Pinus
radiata D. Don plantation (42°52′ S, 172°45′ E) growing in a region subject to summer soil water deficit was
investigated jointly with canopy assimilation (Ac) and ecosystem–atmosphere C exchange rate (net
ecosystem productivity, NEP) (Arneth et al., 1998).
Net primary productivity was derived from biweekly stem diameter growth measurements using allometric
relations, established after selective tree harvesting, and a litterfall model. Estimates of Ac and NEP were
used to drive a biochemically based and environmentally constrained model validated by seasonal eddy
covariance measurements. Over three years with variable rainfall, NPP′ varied between 8.8 and 10.6 Mg C
ha−1 year−1, whereas Ac and NEP were 16.9 to 18.4 Mg C ha−1 year−1 and 5.0–7.2 Mg C ha−1 year−1,
respectively. At the end of the growing season, C was mostly allocated to wood, with nearly half (47%) to
stems and 27% to coarse roots. On an annual basis, the ratio of NEP to stand stem volume growth rate was
0.24 ± 0.02 Mg C m−3. The conservative nature of this ratio suggests that annual NEP can be estimated from
forest yield tables. On a biweekly basis, NPP′ repeatedly lagged Ac, suggesting the occurrence of
intermediate C storage. Seasonal NPP′/Ac thus varied between nearly zero and one. On an annual basis,
however, NPP′/Ac was 0.54 ± 0.03, indicating a conservative allocation of C to autotrophic respiration. In the
water-limited environment, variation in C sequestration rate was largely accounted for by a parameter
integrative for changes in soil water content. The combination of mensurational data with canopy and
ecosystem C fluxes yielded an estimate of heterotrophic respiration (NPP′ – NEP) approximately 30% of NPP′
and approximately 50% of NEP. The estimation of fine-root turnover rate is discussed.
Ellsworth,D.S. 2000. Seasonal CO2 assimilation and stomatal limitations in a Pinus taeda canopy.
Tree Physiol., 20 (7): 435-445.
Net CO2 assimilation (Anet) of canopy leaves is the principal process governing carbon storage from the
atmosphere in forests, but it has rarely been measured over multiple seasons and multiple years. Ellsworth
(2000) measured midday Anet in the upper canopy of maturing loblolly pine (Pinus taeda L.) trees in the
piedmont region of the southeastern USA on 146 sunny days over 36 months. Concurrent data for leaf
conductance and photosynthetic CO2 response curves (Anet–Ci curves) were used to estimate the relative
importance of stomatal limitations to CO2 assimilation in the field. In fully expanded current-year and 1-yearold needles, midday light-saturated Anet was constant over much of the growing season (5–6 μmol CO2 m−2
s−1), except during drought periods. During the winter season (November – March), midday Anet of
overwintering needles varied in proportion to leaf temperature. Net CO2 assimilation at light saturation
occurred when daytime air temperatures exceeded 5–6 °C, as happened on more than 90% of the sunny
winter days. In both age classes of foliage, winter carbon assimilation accounted for approximately 15% of
the daily carbon assimilation on sunny days throughout the year, and was relatively insensitive to year-toyear differences in temperature during this season. However, strong stomatal limitations to Anet occurred as
a result of water stress associated with freezing cycles in winter. During the growing season, droughtinduced water stress produced the largest year to year differences in seasonal CO2 assimilation on sunny
days. Seasonal Anet was more drought sensitive in current year needles than in 1 year old needles. Relative
stomatal limitations to daily integrated Anet were approximately 40% over the growing season, and summer
drought rather than high temperatures had the largest impact on summer Anet and integrated annual CO2
uptake in the upper crown. Despite significant stomatal limitations, a long duration of near-peak Anet in the
upper crown, particularly in 1-year-old needles, conferred high seasonal and annual carbon gain (Ellsworth ,
2000) .
Hall, M., B.E. Medlyn, G.Abramowitz, O.Franklin, M.Räntfors, S.Linder dan G.Wallin. 2013.
Which are the most important parameters for modelling carbon assimilation in boreal Norway
spruce under elevated [CO2] and temperature conditions?. Tree Physiol., 33(11): 1156-1176.
Photosynthesis is highly responsive to environmental and physiological variables, including
phenology, foliage nitrogen (N) content, atmospheric CO2 concentration ([CO2]), irradiation (Q),
air temperature (T) and vapour pressure deficit (D). Each of these responses is likely to be
modified by long-term changes in climatic conditions such as rising air temperature and [CO2].
When modelling photosynthesis under climatic changes, which parameters are then most
important to calibrate for future conditions?. Hall et al. (2013) used measurements of shoot
carbon assimilation rates and microclimate conditions collected at Flakaliden, northern Sweden.
Twelve 40-year-old Norway spruce trees were enclosed in whole-tree chambers and exposed to
elevated [CO2] and elevated air temperature, separately and in combination. The treatments
imposed were elevated temperature, +2.8 °C in July/August and +5.6 °C in December above
ambient, and [CO2] (ambient CO2 ∼370 μ mol mol−1, elevated CO2 ∼700 μ mol mol−1). The [CO2]
treatment increased annual shoot carbon (C) uptake by 50%. Most important was effects on the
light response curve, with a 67% increase in light-saturated photosynthetic rate, and a 52%
increase in the initial slope of the light response curve. An interactive effect of light saturated
photosynthetic rate was found with foliage N status, but no interactive effect for high
temperature and high CO2. The air temperature treatment increased the annual shoot C uptake
by 44%. The most important parameter was the seasonality, with an elongation of the growing
season by almost 4 weeks. The temperature response curve was almost flat over much of the
temperature range. A shift in temperature optimum had thus an insignificant effect on modelled
Dewar,R.C. dan M.G.R. Cannell. 1992. Carbon sequestration in the trees, products and soils of
forest plantations: an analysis using UK examples. Tree Physiol., 11(1): 49-71
A carbon-flow model for managed forest plantations was used to estimate carbon storage in UK plantations
differing in Yield Class (growth rate), thinning regime and species characteristics. Time-averaged, total
carbon storage (at equilibrium) was generally in the range 40–80 Mg C ha−1 in trees, 15–25 Mg C ha−1 in
above- and belowground litter, 70–90 Mg C ha−1 in soil organic matter and 20–40 Mg C ha−1 in wood
products (assuming product lifetime equalled rotation length). The rate of carbon storage during the first
rotation in most plantations was in the range 2–5 Mg C ha−1 year−1 (Dewar dan Cannell, 1992).
A sensitivity analysis revealed the following processes to be both uncertain and critical: the fraction of total
woody biomass in branches and roots; litter and soil organic matter decomposition rates; and rates of fine
root turnover. Other variables, including the time to canopy closure and the possibility of accelerated
decomposition after harvest, were less critical. The lifetime of wood products was not critical to total carbon
storage because wood products formed only a modest fraction of the total.
The average increase in total carbon storage in the tree–soil–product system per unit increase in Yield Class
(m3 ha−1 year−1) for unthinned Picea sitchensis (Bong.) Carr. plantations was 5.6 Mg C ha−1. Increasing the
Yield Class from 6 to 24 m3 ha−1 year−1 increased the rate of carbon storage in the first rotation from 2.5 to
5.6 Mg C ha−1 year−1 in unthinned plantations. Thinning reduced total carbon storage in P. sitchensis
plantations by about 15%, and is likely to reduce carbon storage in all plantation types (Dewar dan Cannell,
1992).
If the objective is to store carbon rapidly in the short term and achieve high carbon storage in the long term,
Populus plantations growing on fertile land (2.7 m spacing, 26-year rotations, Yield Class 12) were the best
option examined. If the objective is to achieve high carbon storage in the medium term (50 years) without
regard to the initial rate of storage, then plantations of conifers of any species with above-average Yield
Classes would suffice. In the long term (100 years), broadleaved plantations of oak and beech store as much
carbon as conifer plantations. Mini-rotations (10 years) do not achieve a high carbon storage (Dewar dan
Cannell, 1992).
Ibrom,A., P.G. Jarvis, R.Clement, K.Morgenstern, A.Oltchev, B.E. Medlyn, Y.P.Wang, L.Wingate,
J.B. Moncrieff dan G.Gravenhorst. 2006. A comparative analysis of simulated and observed
photosynthetic CO2 uptake in two coniferous forest canopies. Tree Physiol., 26 (7): 845-864
Gross canopy photosynthesis (Pg) can be simulated with canopy models or retrieved from
turbulent carbon dioxide (CO2) flux measurements above the forest canopy. We compare the
two estimates and illustrate our findings with two case studies. We used the three-dimensional
canopy model MAESTRA to simulate Pg of two spruce forests differing in age and structure.
Model parameter acquisition and model sensitivity to selected model parameters are described,
and modeled results are compared with independent flux estimates.
Despite higher photon fluxes at the site, an older German Norway spruce (Picea abies L. (Karst.))
canopy took up 25% less CO2 from the atmosphere than a young Scottish Sitka spruce (Picea
sitchensis (Bong.) Carr.) plantation (Ibrom et al., 2006). The average magnitudes of Pg and the
differences between the two canopies were satisfactorily represented by the model. The main
reasons for the different uptake rates were a slightly smaller quantum yield and lower
absorptance of the Norway spruce stand because of a more clumped canopy structure. The
model did not represent the scatter in the turbulent CO2 flux densities, which was of the same
order of magnitude as the non-photosynthetically-active-radiation-induced biophysical
variability in the simulated Pg. Analysis of residuals identified only small systematic differences
between the modeled flux estimates and turbulent flux measurements at high vapor pressure
saturation deficits (Ibrom et al., 2006). .
Baldocchi,D.D. and C. A. Vogel. 1996. Energy and CO2 flux densities above and below a
temperate broad-leaved forest and a boreal pine forest. Tree Physiol., 16 (1-2): 5-16.
Fluxes of carbon dioxide, water vapor and energy were measured above and below a temperate broadleaved forest and a boreal jack pine (Pinus banksiania Lamb.) forest by the eddy covariance method. The aim
of the work was to examine differences between the biological and physical processes that control the fluxes
of mass and energy over these disparate forest stand types (Baldocchi dan Vogel, 1996) .
Carbon and latent heat flux (LE) densities over the temperate broad-leaved forest were about three times
larger than those observed over the boreal forest. Available energy was the key variable modulating LE over
the temperate broad-leaved forest, whereas LE over the boreal jack pine stand was sensitive to variations in
water vapor pressure deficits (VPDs) and available energy. It was also noted that VPDs had different impacts
on transpiration rates of the two forest stands. Increasing VPDs forced a negative feedback on jack pine
transpiration, whereas transpiration rates of the well-watered broad-leaved forest responded favorably to
increasing VPDs (Baldocchi dan Vogel, 1996) .
Carbon dioxide flux densities over the broad-leaved forest stand were more sensitive to changes in absorbed
photosynthetic photon flux density than those over the boreal forest. The efficiency of CO2 uptake over the
jack pine stand was reduced, in part, because the low leaf area of the stand caused a sizable fraction of
available quanta to be absorbed by nonphotosynthetic organs, such as limbs and trunks. Over both forest
stands, variations in photosynthetic photon flux density of photosynthetically active radiation (QP) explained
only 50 to 60% of the variance of CO2 exchange rates (Baldocchi dan Vogel, 1996) . Consequently, caution
should be exercised when scaling carbon fluxes to regional scales based on unmodified, satellite-derived
indices.
The more open nature of the boreal jack pine forest caused water vapor, CO2 and heat fluxes at the forest
floor to be a significant component of whole canopy mass and energy exchange rates. About 20 to 30% of
net canopy mass and energy exchange occurred at the forest floor. Much smaller rates of mass and energy
exchange occurred under the temperate broad-leaved forest.
Goulden,M.L. dan P. M. Crill. 1997. Automated measurements of CO2 exchange at the moss
surface of a black spruce forest. Tree Physiol ., 17 (8-9): 537-542.
Goulden dan Crill (1997) used an automated, multiplexing gas-exchange system to
measure the net exchange of CO2 at the surfaces of three shady feather moss and
three exposed sphagnum moss sites in a black spruce forest during 35 days at the end
of the 1995 growing season. Midday gross photosynthesis was 0.5 to 1.0 μmol m−2 s−1
by feather moss and 0.5 to 2.5 μmol m−2 s−1 by sphagnum moss. Photosynthesis by
sphagnum moss was reduced by approximately 70% at 0 °C, and reached a maximum
rate at 8 °C. Nighttime CO2 efflux, the sum of soil and moss respiration was 1 to 2.5
μmol m−2 s−1 above feather moss and 0.5 to 1.5 μmol m−2 s−1 above sphagnum moss at
moss temperatures of 0 to 15 °C. The higher rates of respiration at the feather moss
sites probably reflected a greater belowground input of carbon from black spruce, and
the lower rates of photosynthesis were probably associated with shading by the black
spruce canopy. Photosynthesis by moss accounted for 10 to 50% of whole-forest gross
CO2 uptake measured simultaneously by eddy covariance. Respiration at the moss
surface was 50 to 90% of whole-forest respiration, with a decreasing fraction on warm
nights apparently because of a disproportionate rise in aboveground respiration
(Goulden dan Crill , 1997) .
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