CONSTRUCTION OF TREE GROWTH MODEL BASED CUSP CATASTROPHE THEORY MODEL

We established an experimental region located at Wang Ye Dian forest farm in Chifeng City, Inner Mongolia, China. Within this region, the catastrophe theory model applied for 6 common species single wood volume measurement and calculation to establish a growth model for trees. The experiment was carried out through the actual measurement of the tree height (H), DBH (D), volume (V), diameter (D-0) as the true value. The internal and external accord precision of "V-H-D" model established were conducted by using the improved differential evolution algorithm and edge species model and then the difference between model calculation value and instrument measuring. the results showed that: The overall relative error (RS) of the model is in the range of [0.001, 0.05], the average relative error (E) is in the range of [-0.11, 0.02], the overall prediction accuracy (P) is greater than 80%. The results show that the model is consistent with the northern China 6 single species tree volume. Meanwhile, this study provides a theoretical and practical basis for the study of tree volume and various species of spatial competition.