长苞铁杉群落优势种群高度生态位研究

Height niche characteristics of dominant popula-tions in the Tsuga longibracteata community

基于天宝岩国家级自然保护区内长苞铁杉群落的调查数据 ,以不同高度作为一维资源位状态 ,以个体多度为生态位计测的资源状态指标 ,对群落中的 1 2个优势树种进行了生态位的计测和分析。结果表明 ,长苞铁杉具有较大的生态位宽度值 ,具有一定的稳定性 ;各优势树种 ,均表现出一定程度的对环境适应的相似性和生态位重叠。长苞铁杉与阳性树种柳杉、耐荫树种中偏阳性树种木荷之间的生态位相似性和生态位重叠值比与耐荫性树种深山含笑、细叶青冈之间的都要大。

The community of the endangered and rare plant Tsuga longibracteata in Tianbaoyan National Nature Reserve,Fujian Province,were surveyed by seting six 20 m×30 m quadrats. Based on these data,the niche characteristics of 12 dominant populations were described and analyzed,with height grade as the resource state and tree abundance as the resource state descriptor of niche. The results indicated that Tsuga longibracteata has higher niche breadth value and will sustain stability for a long time;all the dominant populations showed some adaptation to the community enviroment. Tsuga longibracteata has more similarity in niche overlap and niche similarity with shade-intolerant tree species,Cryptomeria fortunei,than with tolerant ones,Michelia maudiae and Castanea mgrsinaefolia. The results would offer scientific theories for reserving of the endangered and rare plant Tsuga longibracteata.