BIOMETRIC MODELS FOR THE ABOVEGROUND BIOMASS OF jUVENILE BLACK LOCUST TREES

The main objective of this study was to derive biometric models for prediction of stem, branch, leaf and total aboveground biomass of juvenile Robinia pseudoacacia L. trees from easily measurable tree and stand characteristics. A two-stage fitting procedure and a set of predefined goodness-of-fit criteria for development of allometric relationships were followed. Linear regression on the log-transformed equation forms was used and the ratio correction for bias was applied to the back-transformed data. We used data from 45 oneto six-year-old trees and we developed two systems of additive, compatible generic equations for aboveground biomass of black locust. A number of model formulations with one and two independent variables was examined, which involved breast height tree diameter and total tree or mean stand height as predictors of dry biomass weight of the aboveground tree components. Model system M1 employs the two principal tree dimensions total height and breast height diameter, while system M2 is based on mean stand height and tree diameter. The models are applicable to estimate the aboveground biomass of juvenile R. pseudoacacia trees of diameter up to 9 cm and total height up to 9 m.