关键词: 川陕哲罗鲑, 方案优化, 环境DNA分析

Abstract: Understanding and modeling the competition relationships of individual trees play an important role in tending of forest plantation. A study was performed to calculate the competition of individual trees of Pinus tabuliformis plantation in Xishan Experiment Forest Farm, Beijing. The competitive intensity was analyzed by modified Hegyi index, and the weighted Voronoi diagram of objective trees was mapped by DBH and relative spatial position in order to determine its competition unit. Take formula S_i=∑〖DD(〗n〖〗j=1〖DD)〗λ〖SX(〗（αij-αi)a〖〗Lb〖SX)〗 as reference to model the competition relationship between an objective tree and other 3 or 4 nearest trees. The results showed that the competition of individual trees was high, especially in plantation with high density and lower slope position. Model combining with the DBH and crown diameter had a lower standard error, with the estimation effects (R²) of 0.83 and 0.84 for 3- and 4-neighborhood competition model, respectively. Based on the analysis of overlapping area of Voronoi diagram and crown canopy, the adjacent competition model of individuals provided a reference for stand structure optimizing and thinning in forest management.

Key words: protocol optimization., eDNA analysis, Hucho bleekeri