Nonlinear Height-DBH Model Analysis For Three Tropical Tree Species In Mt. Makiling, Philippines

Nonlinear growth functions have been commonly used for modeling tree height-diameter at breast height (H-DBH) relationships. The development of a simple yet accurate H-DBH equation to predict the height of individual tree species is a need because using the appropriate model will give precise estimation of the forest inventory resources. In this study, six H-DBH models (CR, EX, KF, ML, SC, and WE) were used to derive and estimate the height of three species in Mt. Makiling, specifically Parashorea malaanonan, Diplodiscus paniculatus, and Celtis luzonica using the DBH as the only predicting variable. The DBH and tree height of the representative trees per species were measured for this study through nondestructive and random sampling. A total of 175 trees represented the P. malaanonan; 178 trees represented D. paniculatus, while 191 trees were measured to represent C. luzonica. Based on the evaluation criteria which include R-2, RMSE, E, AMD, AIC, and AIC(w), the performance of the WE model was determined to be the best in predicting the height of P. malaanonan species while the performance of the KL model was the best both for the D. paniculatus, and C. luzonica species.