Carbon Storage Estimation in Trees in Small Urban Parks in Urban Townships in Selangor, Malaysia

Abstract

This research aims to assess the carbon storage potential of trees in 20 small urban parks (SUPs’) in two local jurisdictions, Petaling Jaya (PJ) and Shah Alam (SA), within Selangor, Malaysia. The SUPs’ role in combating climate change was determined via carbon storage. Specifically, a field inventory method was employed in this study to collect data on key tree parameters such as diameter at breast height (DBH), tree height, and species identification. The Above Ground Biomass (AGB) and carbon storage were estimated through wood specific gravity (WSG) from the existing literature and pantropical allometric equations. Both the PJ and SA carbon storage sum were 207,164.11 kg and 258,706.43 kg, respectively. Resultantly, significant relationships were identified between tree characteristics and carbon storage, with the DBH categories (60.1–75 cm, r = 0.83; 90.1–105 cm, r = 0.70; > 105 cm, r = 0.50) demonstrating the highest positive correlations. Moderate relationships were evidenced with average tree height (r = 0.25) and SDI (r = 0.14). In analysing the generalised linear models (GLM), DBH, mean tree height, Shannon Diversity Index (SDI), tree density, the proportion of exotic species, and park size proved significant predictors of carbon storage. With an adjusted R² of 0.96, AICc of 390 and standard error of 1,117, model 7 reflected the highest R² value and stability among the tested models where the structural traits of trees akin to DBH and height significantly determined carbon storage, with spatial variables such as park space, tree density, and biodiversity metrics (SDI and species diversity) playing supporting roles. These findings are crucial for the management of SUPs’ informing species selection, promoting layered tree planting designs, and efficiently using limited space for carbon storage.

Keywords: Urban Green Space, Carbon Uptake, Urban Trees, Tree Characteristics, Tree Species, Tropical Cities, Climate Change