黄果厚壳桂种内与种间竞争的数量关系

采用Hegyi单木竞争指数模型对鼎湖山季风常绿阔叶林建群种黄果厚壳桂的种内、种间竞争强度进行定量分析.结果表明,黄果厚壳桂所受到的竞争强度随着林木径级的增大而逐渐减小.黄果厚壳桂种内竞争较与伴生树种云南银柴的种间竞争弱.黄果厚壳桂种内和种间竞争强度的顺序为:云南银柴>黄果厚壳桂种内>荷木>白颜树>肖蒲桃>锥栗>红车>臀形果>柏拉木>水石梓>窄叶半枫荷>厚壳桂.整个林分及黄果厚壳桂种内竞争木对对象木的竞争强度与对象木的胸径大小之间的关系近似服从幂函数关系，而伴生树种竞争木对对象木的竞争强度与对象木的胸径大小之间的关系近似服从对数函数关系.竞争强度和对象木的胸径大小呈显著负相关关系.

Quantitative relationships of intra- and interspecific competition in Cryptocarya concinna

The monsoon evergreen broad-leaved forest(MEBF) in Dinghushan Nature Reserve(DNR) has been considered as a zonal vegetation in lower subtropical China,with a history of more than 400 years.In this paper,the intra-and interspecific competition intensity in Cryptocarya concinna,one of the constructive species in MEBF in DNR was quantitatively analyzed by Hegyi single-tree competition index model.The results showed that the intraspecific competition intensity in C.concinna decreased gradually with increasing tree diameter.For C.concinna,its intraspecific competition was weaker than its interspecific competition with Aporosa yunnanensis.The competition intensity of interspecific competition with C.concinna followed the order of A.yunnanensis > Schima superba > Gironniera subaequalis > Acmena acuminatissima > Castanopsis chinensis >Syzygium rehderianum >Pygeum topengii > Blastus cochinchinensis >Sarcosperma laurinum > Pterospermum lanceaefolium > Cryptocarya chinensis.The relationship of the DBH of objective tree and the competition intensity between competitive tree and objective tree in the whole forest and C.concinna population nearly conformed to power function,while that between other competitive tree and the objective C.concinna tree conformed to logarithm function.There was a significantly negative correlation between the competition intensity and the DBH of objective tree.