Above-ground biomass estimation of mangrove forest using WorldView-2 imagery in Perancak Estuary, Bali

Abstract

Global warming is the important issues because is caused by the concentration increase of greenhouse gasses in the atmosphere. Mangrove ecosystem has a function to reduce climate change through carbon sequestration. Estimates of biomass can be done through an approach from the value of vegetation biomass. Allometric equations method is used for calculating biomass values. Remote sensing technology is used for mapping mangrove ecosystems to determine the spatial distribution of mangrove biomass that is WorldView-2 (WV-2) image. Transformation of the vegetation index are Normalized Difference Vegetation Index (NDVI) and Soil Adjusted Vegetation Index (SAVI) are used to estimate of mangrove forest biomass. The aim of this study is to determine the most accurate vegetation index in estimating the mangrove above-ground biomass (AGB) value. The field biomass data was obtained from mangrove tree diameter at breast height (DBH) measurement. Using the allometric equation, the field AGB can be calculated. A regression analysis between field biomass and WV-2 image pixel value was performed to build regression function to estimate the mangrove AGB. The results of this study show that the SAVI provided higher accuracy for mangrove AGB estimation with R2 of 0.4125 and resulting the AGB value between 1124.81 to 4499.25 kg/m.