论文部分内容阅读
理解物种丰富度在空间上的变化,阐明植物群落组成对生境异质性的响应是群落生态学研究的核心议题之一。与生境异质性有关的生态位分化对植物群落的多样性格局和物种分布具有重要影响。本文以分布在云南哀牢山的4种常绿阔叶林为研究对象,通过对42个森林样地的调查取样,探讨了常绿阔叶林的群落分布和树种丰富度在地形和土壤环境梯度上的变异。结果表明:4种常绿阔叶林的树种组成有显著的差异。季风常绿阔叶林的树种丰富度极显著地高于其他3种类型;中山湿性常绿阔叶林极显著地高于半湿润常绿阔叶林;其他类型之间的差异不显著。非度量多维尺度分析显示,海拔、坡度、土壤含水率及有机质等9个环境梯度是控制森林群落结构和树种分布的主要因素。土壤有效硼、海拔、全钾和凹凸度为树种丰富度的最佳预测变量,累积解释了树种丰富度63.2%的变异。地形和土壤因子一起能够解释哀牢山常绿阔叶林的群落组成和树种丰富度的大部分变异。
Understanding the spatial variability of species richness and elucidating the response of plant community composition to habitat heterogeneity is one of the core topics in the study of community ecology. Ecological niche differentiation related to habitat heterogeneity has an important impact on the diversity and distribution of plant communities. In this paper, four kinds of evergreen broad-leaved forests distributed in Ailao Mountain, Yunnan Province were selected as research objects. Through sampling and sampling of 42 forest plots, the community distribution and tree species richness of evergreen broad-leaved forest in topography and soil environment Gradient variation. The results showed that there were significant differences among the four species of evergreen broad-leaved forest. The monsoon evergreen broad-leaved forest species richness is extremely significantly higher than the other three types; Zhongshan wetland evergreen broad-leaved forest is significantly higher than semi-humid evergreen broad-leaved forest; other types of differences are not significant. Non-metric multidimensional scaling analysis shows that nine environmental gradients, such as elevation, slope, soil moisture and organic matter, are the main factors that control the distribution of forest community structure and tree species. Soil available boron, elevation, total potassium and concavity and convexity were the best predictors of tree species richness, which explained 63.2% variation of species richness cumulatively. Topography and soil factors together can account for most of the variation in community composition and tree species richness in the evergreen broad-leaved forest in Ailao Mountain.