云南榧树群落种内与种间竞争研究

为探讨云南榧树竞争关系和动态规律，在其群落样地踏勘的基础上，采用Hegyi单木竞争模型对云南榧树种群的种内和种间竞争进行定量分析。结果表明，不同树种对云南榧树的种间竞争存在着差异，云南榧树受到种间竞争强度由大到小顺序为:川滇高山栎、胡桃、飞蛾槭、栗等。云南榧树的种内竞争强度与种间竞争强度的总和大致相同，种内和种间竞争强度均随着径级的增加而逐渐减小。对象木胸径与竞争强度之间服从幂函数关系C_I=AD^-B，胸径大于10 cm受到的竞争压力处于较低水平，且变化幅度不明显，利用该模型能很好地预测云南榧树种内和种间竞争强度。

Intra-and Inter-specific Competition of Torreya yunnanensis Community

Torreya yunnanensis is a second-class protected wild plant in China.In order to explore the competition relationship and dynamic rules of T.yunnanensis,based on the survey of the community plots,the intra-and inter-specific competitions of T.yunnanensis were quantitatively analyzed by using Hegyi single-tree competition model.The results showed that the inter-specific competition of different tree species to T.yunnanensis was different,the order of the intensity of inter-specific competition for T.yunnanensis wass Quercus guyavaefolia,Juglans regia,Acer oblongum,Castanea mollissima,etc.The intensity of intra-specific competition of T.yunnanensis was similar to that of inter-specific competition,the intra-and inter-specific competition intensity of T.yunnanensis decreased with the increase of the tree diameter.The relationship between the competition intensity and DBH of T.yunnanensis followed the power function(CI=AD^-B).When the DBH was greater than 10 cm,the competitive pressure on T.yunnanensis was less and tended to stabilize.The model can be used to predict the intra-and inter-specific competition of T.yunnanensis.