Biomass expansion factors of Olea ferruginea (Royle) in sub tropical forests of Pakistan

Wood biomass gives information about total productivity of the forest as well as individual tree. Olea ferruginea (Royle) which is small and evergreen is widely distributed in native sub tropical forests of Pakistan and extensively used as fuelwood domestically. This study was carried out in the sub tropical forests of Pakistan at 33 degrees 38' north and 73 degrees 00' east latitude and longitude, respectively, and at an elevation of 917 m. Trees with exploitable diameter were selected randomly from the entire forest. Destructive sampling techniques were used for measuring biomass (kgm(-3)) in all the tree components. For this purpose, 5 trees were felled and the biomass of each component of the tree including main stem, branches, leaves, twigs and roots were estimated separately using volume, weight and density. The generic data of wood density (kgm(-3)) was used to determine the biomass (kg). The study showed that average contribution of stem portion of the tree was 49.01% of the total tree biomass, and branches showed 31.17%, leaves 1.98%, twigs 1.05% and roots 16.65% of the total tree biomass. So, it was found that the major part of the total tree biomass was present in the stem portion of O. ferruginea. Total volume of the tree was also found to be dependent on the diameter of the tree. Mean volume of the tree was 0.475 +/- 0.07 m(3). The prepared biomass expansion factor will be helpful in estimating productivity, carbon stocks and yield of the forest.