广东南岭国家级自然保护区华南五针松种内和种间关系研究

Interspecific and intraspecific competitions of Pinus kwangtungensis in Nanling National Nature Reserve, Guangdong Province of southern China

【目的】通过对广东南岭国家级自然保护区小黄山内118株对象木及253株伴生种的调查,分析华南五针松的竞争强度,揭示华南五针松群落的动态变化规律和种群生态适应机制。【方法】沿海拔梯度设置标准群落样方。利用Hegyi单木竞争模型计算华南五针松群落内物种间的竞争指数,并采用回归分析的方法建立对象木胸径与林分、种间竞争强度的函数模型。【结果】(1)华南五针松胸径与树高存在显著的幂函数关系;(2)华南五针松的种内和种间竞争指数分别为893.736和559.682;(3)华南五针松伴生种较多,其主要种间竞争树种的顺序为木荷>甜槠>五列木>马尾松>长苞铁杉>凤凰木>福建柏>马蹄荷;(4)华南五针松胸径与整个林分和种间竞争指数呈显著的负相关。【结论】华南五针松群落内以种内竞争为主。竞争强度随华南五针松个体胸径的增大而减小,当华南五针松胸径到达30 cm时,竞争强度下降较为平稳,二者符合幂函数关系,所得模型能有效的预测华南五针松的种内和种间强度。

[Objective] In order to reveal the rule of dynamic changes of competition intensity within the community and the ecological adaptation mechanism, the intraspecific and interspecific competition of Pinus kwangtungensis were analyzed by investigating the 118 target trees and 253 associated species in Xiaohuangshan of Nanling National Nature Reserve, Guangdong Province of southern China. [Method] We set standard community plots along the elevation gradient. The competition index of P. kwangtungensis was calculated by Hegyi individual competitive indices(CI) model. The function model between DBH, the competitive index of stand, and interspecific competition were established by regression method.[Result](1) There was a significant power function relationship between DBH and tree height.(2) Intraspecific and interspecific competition intensities of P. kwangtungensis were 893.736 and 559.682,respectively.(3) There were many associated species of P. kwangtungensis, and the order of main interspecific competition species was Schima superba > Castanopsis eyrei > Pentaphylax euryoidex > Pinus massoniana > Tsuga longibracteata > Delonix regia > Fokienia hodginsii > Exbucklandia populnea.(4) There was a significantly negative correlation between the competition index with the stand,accompanying species, and the DBH of the objective trees. [Conclusion] Intraspecific competition was dominant in the community. The competition intensity of P. kwangtungensis decreases inversely with the growth of DBH. When the DBH of P. kwangtungensis reached 30 cm, the competition intensity declined stably, and the relationship between the forest stand competition intensity and DBH of the target trees is conformed to power function. This model can effectively predict the intraspecific and interspecific competitions of P. kwangtungensis.