Factors Determining Maximum Above Ground Biomass Accumulation in Awuria Dry Afromontane Forest in Cheha District of Gurage Zone, Central Ethiopia Region

Tree spacing significantly influences its morphology, productivity, and biomass accumulation. The objective of this study was to understand factors determining above ground biomass accumulation of selected focal trees in Awuria forest. Two the most dominant tree species were selected as focal trees. Species name, neighbor tree distance from focal tree, crown diameter, and DBH of focal and the four nearest neighbor tree species were recorded during data collection. The biomass of each focal tree was estimated using Chave et. al. (2014) allometric equations. Mean distance, neighbor density index, and the mean DBH of neighbor trees were determined through descriptive statistical analysis. The competition index was analyzed using Hegyi’s competition index formula. Generalized additive model was used to fit above ground biomass of the focal tree. Competition index, mean neighbor distance, and mean neighbor tree DBH were fitted as independent variables in GAM model to determine their biomass prediction potential. The optimum tree spacing was determined for each focal tree species. Competition index and mean neighbor DBH showed strong potential to determine above ground biomass of the selected focal trees. The optimum tree spacing for A. falcatus and J. procera were 1 and 1.8 meters, respectively.