Development of tree biomass model for Pinus koraiensis plantation

Based on the data of tree biomass for Korean pine(Pinus koraiensis) plantations, the optimal model of tree biomass for Korean pine had been selected by using the method of nonlinear simultaneous equations with measure error. Based on the total biomass and stem biomass as restrictions，the compatible tree biomass equations between the total biomass and each components of tree (stem, branches, foliages, and roots) were developed. Meanwhile, the weighted regression method was used to eliminate heteroscedasticity. The results showed that the coefficients of determination (R2) and the modeling efficiency (EF) were 0.80-0.99 and 0.82-0.98 respectively for the optimal base models and compatible biomass models. The most of the prediction accuracy was larger than 82% for tree biomass models of total and each component, where the effects of prediction accuracy were better for stem biomass and the worst for foliage. On the whole, the compatible tree biomass models developed on the total biomass as restriction were little better than stem biomass as restriction. There were no significant differences between statistics of goodnessoffit and validation for the optimal base models and compatible models of tree biomass. The conclusion is that the two kinds of compatible biomass equations developed in the paper can effectively estimate the tree biomass for Korean pine plantations.