Allometric equations for pioneer tree species and estimation of the aboveground biomass of a tropical secondary forest in East Kalimantan

To estimate the aboveground biomass of tropical secondary forests dominated by pioneer species, allometric equations to relate diameter at breast height with the dry mass of the aboveground organs of several pioneer species were developed. The aboveground biomass of secondary forests was estimated using four methods based on the allometric equations. Biomass estimated with an allometric equation for all species combined was equivalent to that estimated with species-specific allometric equations. However, the estimated biomass based on a general-purpose allometric equation was substantially higher than that using other allometric equations. The allometric equation for all species combined is suitable for estimating the biomass of a secondary forest from the view points of accuracy and labor.