Carbon Sequestration Potential of Urban Trees

Transcription

1 Carbon Sequestration Potential of Urban Trees Prachi Ugle 1, Sankara Rao 2 and T.V Ramachandra 1, 2 Source: Google 1 Centre for Infrastructure, Sustainable Transport and Urban Planning, IISc, Bangalore, India 2 Centre for Ecological Sciences, IISc, Bangalore, India 1

2 Carbon Sequestration The capture and secure storage of carbon that would otherwise be emitted to or remain in the atmosphere (US, Dept. of Energy) is referred as Carbon Sequestration 2

3 Global Carbon Cycle Carbon exists in everything that is living or has ever lived. There is a perpetual cycle of carbon being sequestered on earth and emitted back into the atmosphere. Human kind is increasingly influences this very perpetual cycle. Carbon sequestration occurs within is a part of carbon cycle, IPCC, 1997 Carbon sequestration is one of the important clause of Kyoto protocol and has provided a special purpose vehicle for considering the role it will play in climate change mitigation 3

4 Rationale of the Study Why focus on urban areas? What is our understanding of urban trees? Why focus on urban trees emerging as a new trend? What is the carbon sequestration potential of urban trees? 4

5 Paradox Cities are viewed negatively because of their huge carbon footprint Urban areas are major emitters of greenhouse gases Urban areas are highly vulnerable to impacts of climate change 5

6 Which urban trees? Streets Parks Private Non-forested but tree dominated areas like university campus, including avenues and public gardens - comes under cities and infrastructure Ecological value in urban landscapes 6

7 Why Urban Trees : Ecosystem Services & A Package of Other Benefits Urban trees are considered to be central part of green infrastructure Amelioration of urban climate extremes Store and Sequester Carbon Improve Air Quality Reduce noise pollution Improve property value Aesthetic contribution, visual amenity Improve general livability and quality of urban life Source: Google 7 Planting trees in cities a practice as old as cities themselves.

8 Carbon Storage Overview Photosynthesis captures carbon 6CO 2 + 6H 2 O + sunlight C 6 H 12 O 6 + 6O 2 Some of the sugar is stored, while most of it gets used by the tree for energy and structure If we look at sugar from a mass standpoint, a large fraction of it is due to the carbon Each CO 2 molecule has an atomic mass of 12 +2(16) = 44, the ratio of CO 2 :C = 44/12=3.67 Validity Trees to capture and store carbon 8

9 Urban Trees : Carbon Sequester Urban Trees 0.2 million tonnes of C is stored by 2.4 million trees in Beijing Carbon Stored is 23.8 million tonnes from an estimated 7.7 million ha urban area Contribute 2.21% of carbon stock against carbon/ha from over all forest and tree cover 15,000 tonnes/yr - Carbon Sequestration potential of trees, Pune, India Source Yang etal, 2004 National Mission For Green India, 2009 National Mission For Green India, 2009 Warren and Patwardhan, 2005 Source: carbonzeroplanet.org 9

10 Urban Green Sweet Spots of Bangalore Cubbon Park IISc Lal Bagh IISc campus which spans over 400 acres of land in the middle of the city is one of the rich species centers of Bangalore 10

11 Methodology Data Collection: Trees are located accurately using GPS and identified to species level. Tree diameter measured at 1.3 m above ground (DBH) Tree Distribution The percentage of trees in dbh classes is carried out as it indicates the age structure distribution. Tree Height Measurement Using Clinometer Biomass and Carbon: 1. Species specific biomass equations available in the literature 2. Volume and wood density estimations (Brown, 1997) 50% of the dry biomass can be inferred as carbon. (Westlake, 1966, Brown & Lugo 1982, Houghton et al. 1985; Koch 1989, Schroeder 1992, Dixon 1994; Cannel etal,1995, Richter etal, 1995; Ravindranath etal, 1997, Montagnini and Porras, 1998, Losi etal, 2003, Montagu etal, 2005). 11

12 Spathodea companulata Kigelia africana Cassia spectabilis Eucalyptus teriticornis Dillenia indica Neolemarckia cadamba 12

13 Tree Inventory Data For IISc Campus, Bangalore 13

14 Table: 1. Tree distribution in DBH Class for the tree species surveyed Species DBH class (cm) for the number of trees surveyed >75 Number of trees surveyed Spathodea companulata Tamarindus indica Polyalthia longifolia Santalum album Neolemarckia cadamba Swietenia mahagoni Michelia champaca Ceiba pentandra Ceiba speciosa Eucalyptus teriticornis Roystenia regia Total

15 Figure: 1. Preliminary Tree Distribution In DBH Class for IISc Campus Spathodea companulata Tamarindus indica Swietenia mahagoni Neolemarckia cadamba Ceiba pentandra Eucalyptus teriticornis 15

16 Table: 2. Preliminary Results: S.No Botanical Name of the Species 1 Tamarindus indica Biomass Equation Wood Density Reference IISc campus, Bangalore Y=exp[ *ln (DBH) *(ln(DBH)) 2 - IPCC GPG, 2006, Pearson etal,2005 Biomass in tonnes/tree Carbon in tonnes/tree Mangifera indica Y=exp[ *ln (DBH) *(ln(DBH)) 2 - IPCC GPG, 2006, Pearson etal, Gmelina arborea V = D D Ficus religiosa V= D 2 H 0.385* 5 Ceiba pentandra V= D * 16 FSI, 2009, *Brown, FA0,1997 FSI, 1996, *JTDA, 1985 FSI, 1996, *Brown, FA0, Polyalthia longifolia Y=exp[ *ln (DBH) *(ln(DBH)) 2 - Pearson etal, Roystenia regia Y=exp[ *ln (DBH) *(ln(DBH)) 2 - Pearson etal, Ceiba speciosa Y=exp[ *ln (DBH) *(ln(DBH)) 2 - Pearson etal, Neolemarckia cadamba Y=exp[ *ln (DBH) *(ln(DBH)) 2 - Pearson etal, FSI, 2009, 10 Butea monosperma V = D 0.48* *Brown, FA0,

17 Conclusions Research in the direction of estimation of tree biomass and diameter distribution helps in determining which tree species are best for carbon sequestration. The estimates generated can be used to take up strategic tree planting programmes. 17

18 References 1. Behera, G., Nageshwara Rao.P.P, Dutt.C.B.S, Manikiam.B, Balakrishnan.P, Krishnamurthy.J, Jagadeesh.K.M, Ganesha Raj.K, Diwakar.P.G, Padmavathy.A.S and Parvathy.R Brown,S, Estimating biomass and biomass change of tropical forests: a primer Food and Agriculture Organization of the United Nations, Brown, S. & Lugo.A.E, The storage and production of organic matter in tropical forests and their role in the global carbon cycle. Biotropica 14: Dwivedi, P., C. S. Rathore and Y. Dubey Ecological benefits of urban forestry: The case of Kerwa Forest Area (KFA), Bhopal, India. Applied Geography 29(2): FSI State of Forest Report Forest Survey of India, Ministry of Environment & Forests, Dehradun. 6. IPCC, Climate Change 2001: Working Group I: The Scientific Basis. Cambridge University Press, New York. 7. Jim, C. Y. and Liu, H. H. T Statutory measures for the protection and enhancement of the urban forest in Guangzhou City, China. Forestry 73: Ketterings, Q.M., R. Coe, M. van Noordwijk, Y. Ambagau & C.A. Palm Reducing uncertainty in the use of allometric biomass equations for predicting aboveground tree biomass in mixed secondary forests. Forest Ecology and Management 146: Losi, C.J., Siccama, T.G., Condit, R. and Morales, J.E., Analysis of alternative methods for estimating carbon stock in young tropical plantations. Forest Ecology and Management, 184(1-3): Nagendra, H. and D. Gopal Street trees in Bangalore: Density, diversity, composition and distribution. Urban Forestry & Urban Greening: /j.ufug Parresol, B.R., Assessing tree and stand biomass: a review with examples and critical comparisons. Forest Sci. 45,

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