Relationship between Height and Stump Diameter for Terminalia Ivorensis (A.Chev) in Sokponba Forest Reserve, Edo State, Nigeria

Abstract

Height (H) and Diameter (D) data from Terminalia ivorensis stand were assessed to establish a relationship between height and stump diameter. Two hundred and sixteen (216) individual trees from eighteen randomly selected Temporary sample plots (TSPs) within a forty-year old plantation were used in study. The data collected were fitted to seven different regression models; of which the logarithmic model was adjudged the best, based on regression statistics diagnostic criteria. The equation is LogH = 1.2493 + 0.005LogD with the adjusted coefficient of determination (adj. R²) and overall standard error of 0.9907 and 0.028 respectively and thus found being the best goodness of fit model. Residual analysis showed conformity with the assumption of independence errors in regression analysis. The equations were validated using another set of trees that were not part of those used for estimating the model parameters. No significant difference (p > 0.05) was obtained when the predicted and the observed values were compared using ANOVA and Duncan Multiple Range Test.