Models for estimating tree volume, above-and belowground biomass for acacia-commiphora woodlands in Same district, Tanzania

Reduced Emissions from Deforestation and Degradation (REDD) framework demands measuring of carbon stock changes. In most cases, estimates of carbon stocks rely on volume and biomass estimation allometric models. Although species-specific and some generic models for biomass and volume estimation have been developed for some vegetation types such as Miombo woodlands, their use in Acacia-Commiphora woodlands in dry areas is questionable as they comprise short-height trees with small to medium tree diameters scattered from each other. This necessitates the need to develop robust generic allometric models that accounts for the heterogeneity of tree diversity in the Acacia- Commiphora woodlands in dry areas. Allometric models for volume and biomass estimation were developed by means of destructive sampling of 60 trees with DBH distribution ranging from 2.50 to 30.30 cm. Four different model forms were tested and the best model for estimating tree’s section biomass and volume were selected based on the lowest values of Residual Standard Error (RSE) and Akaike Information Criterion (AIC). All selected models had their parameter estimates significantly different from zero (P