中文摘要：

群落构建机制一直是群落生态学研究的核心问题.群落系统发育和功能性状的α及β多样性为探讨生态位过程和中性过程在局域群落构建中的相对作用提供了新的视角.本研究以哀牢山6 hm2中山湿性常绿阔叶林动态监测样地为研究平台,基于DNA条形码构建的群落系统发育树和树种8个关键功能性状,结合地形数据,分析不同生活史阶段树种在不同空间尺度的系统发育和功能性状α及β多样性.研究表明：（1）各生活史阶段树种在不同空间尺度上均表现出非随机的系统发育和功能性状结构,系统发育和功能性状聚集程度随空间尺度的增大而增大;（2）在所有空间尺度上,系统发育和功能性状的周转都为非随机,并且环境距离对系统发育和功能性状β多样性的解释程度均高于空间距离.研究结果揭示了环境过滤在中山湿性常绿阔叶林群落构建中起主导作用.

英文摘要：

Understanding the mechanisms of community assembly is a key issue in the study of biodiversity. Phylogenetic and functional alpha and beta diversity can provide new insights into the relationships of stochastic and deterministic processes underpinning community assembly. To reveal the mechanisms underlying community assembly of mid-mountain humid evergreen broad-leaved forest, we studied a 6-ha forest dynamics plot in the Ailao Mountains of southwestern China. We used molecular phylogeny, eight functional tree-species traits, topographic variation and spatial data to analyze the phylogenetic and functional structure and beta diversity of the tree assemblages. Non-random phylogenetic and functional structure was found in each tree size class across all spatial scales. As spatial scales increased, we observed more extensive phylogenetic structure and greater clustering of functional traits. The turnover of lineages and species functions between subplots was generally non-random. Compared with geographic distance, environmental distance better explained the observed variation in phylogenetic and functional turnover. Our results reveal that environment is the most important factor influencing species filtering in mid-mountain humid evergreen broad-leaved forest.