Spatial Interpolation of Above-Ground Biomass in Labanan Concession Forest in East Kalimantan, Indonesia

摘要

This study applied a geostatistical approach to quantify above-ground biomass (AGB) of the Labanan Concession Forest in East Kalimantan, Indonesia. Forest inventory data collected via transect sampling were converted to AGB, and two approaches of estimating the spatial distributions of biomass, the global and stratified approaches, were compared. The global approach does not take local varying structures into account, whereas the stratified approach accounts for the heterogeneity of land cover types. Thus, AGBs estimated from each land cover type were pooled for the stratified approach. Ordinary kriging was performed to predict AGB at unsampled locations. The total estimates of AGB and RMSCVEs for the global and stratified methods were 13,512,392.2 tons (161.92 ton/ha) and 13,607,205.5 tons (163.05 ton/ha), respectively, for AGB and 81.0 ton/ha and 81.2 ton/ha, respectively, for RMSCVE. Considering the different environmental conditions for each land cover type, the stratified method was expected to better capture the spatial structure particular to each land cover type, leading to more accurate estimates of AGB. However, the results suggest the degree of accuracy for the two methods was nearly similar.