Modeling diameter distribution for Sakponba Forest Reserve, Edo State, Nigeria

Tree diameter distributions play an important role in stand performance. Diameter distribution model was developed for Sakponba Forest Reserve. Systematic sampling technique was adopted. A total of 613 trees were measured in 96 sample plots. Diameter at breast height (dbh) at 1.3m above ground data were measured for tree species with dbh ≥ 10cm in the confines of the sampling units. Data collected were analysed using probability density function (pdf), then ranked based on Kolmogorov smirnov. The best six distributions [Log-Logistic (3p), Burr, Dagum, Gen-Logistic, Gen Extreme value and Log normal] were used for fitting the diameter data. The results indicated that the trees in the lower diameter class were more in number than the upper diameter class. Log-Logistic distribution was adjudged more flexible when tested with Kolmogorov smirnov The reason is because the calculated value [Log-Logistic (3P) = 0.04477] was the lowest value and smaller than the tabulated values (D = 0.05 at p ≥ 0.05). This implied that the data followed the specified distribution and that Log-Logistic (3P) can appropriately provide a better fit for the diameter data in Sakponba Forest Reserve. published by the Journal of Biodiversity and Environmental Sciences | JBES