Carbon Sequestration Estimation of Urban Trees in Parks and Streets of Bangkok Metropolitan, Thailand

Abstract

The study estimated the averaged greenhouse gas (GHG) absorption factor of trees planted in urban area in Bangkok using survey data in urban parks and on roadsides to estimate the GHG absorption effect of urban greening. A dataset of tree species in four parks (2,621 trees) and in main/sub-main streets (200,388 trees) in Bangkok surveyed in 2003, 2011, and 2012 were used. The biomass for each species was calculated using allometric equations by parks and streets and conversion factors from the literature to estimate whole tree dry weight biomass and carbon. Allometric equations were sourced from “GlobAllomeTree” (FAO, online) and IPCC (2003). Tree ages were assumed to be the year difference between the surveyed year and the year of park establishment. Annual carbon absorption of trees in four parks ranged between 0.001 and 0.026 tonnes carbon (tC)/tree/year with a weighted average of 0.009 tC/tree/year. Street trees absorbed 0.002-0.015 tC/tree annually with an average of 0.012 tC/tree/year. The results of the present study were within the range of the default values ​​of the IPCC of 0.0033-0.0142 tC/tree annually. It is expected that the results in this study can be applied for evaluation of the urban greening effect in Bangkok and other cities in Thailand and ASEAN countries, as the results the urban greening for mitigation are further promoted.