地理距离及环境差异对云南元江干热河谷植物群落beta多样性的影响  

Impacts of geographical distances and environmental differences on the beta diversity of plant communities in the dry-hot valley of the Yuanjiang River

作　　者：李新辉[1,2] 刘延虹[1,2] 刘晔[3] 许玥[4] 杨阳[4] 沈泽昊[4] 

机构地区：[1]西南林业大学环境科学与工程学院,昆明650224 [2]云南玉溪森林生态系统国家定位观测研究站,云南玉溪653400 [3]北京大学深圳研究生院城市规划与设计学院,广东深圳518055 [4]北京大学城市与环境学院生态学系,地表过程分析与模拟教育部重点实验室,北京100871

出　　处：《生物多样性》2016年第4期399-406,共8页Biodiversity Science

基　　金：国家自然科学基金(41371190);交通运输部西部计划项目(200831879917);云南省高校优势特色重点学科(生态学)建设项目

摘　　要：beta多样性反映了群落间物种组成的差异,是生物多样性研究的热点之一。本研究通过对云南元江干热河谷41个植物群落样方进行调查,用Jaccard相异系数表征物种beta多样性,用样方之间的最近谱系距离(mean nearest taxon distance,MNTD)及平均谱系距离(mean pairwise distance,MPD)表征谱系beta多样性,采用基于距离矩阵的多元回归和方差分解方法,探讨了该区域干热河谷典型植物群落的物种beta多样性和谱系beta多样性与样方间环境差异(主要是气候)及地理距离之间的关系。结果表明:(1)群落间的地理距离和年平均温度差异对干热河谷植物群落的物种beta多样性和谱系beta多样性有显著影响;(2)地理距离对物种beta多样性和MNTD的影响最大;地理距离和年平均温度差异对MPD的影响均较大;(3)样方间年平均温度与年平均降水量的差异和地理距离能够解释群落间beta多样性及谱系beta多样性11–13%的变异。以上结果表明,生态位分化和扩散限制对该地区植物群落的beta多样性均有显著影响,其中扩散限制的影响可能更大。此外,人类活动等其他因素也很可能对元江干热河谷的群落组成具有非常重要的影响。Beta diversity is the difference in species composition between locations. Recently, much of the published biodiversity research has focused on the assessment of beta diversity because it can be used to investigate community assembly and maintenance of species diversity. In this study, we investigated the impacts of dispersal limitation and habitat on the beta diversity of communities by sampling 41 plots throughout the dry-hot valley of Yuanjiang River. Taxonomic beta diversity and phylogenetic beta diversity were quantified using Jaccard dissimilarity, mean nearest taxon distance（MNTD）, and mean pairwise distance（MPD）. These indices were then related to the differences in environmental characteristics between sample plots and the geographical distances separating sample plots using multiple regression on distance matrices（MRM） and variance partitioning. The results showed that taxonomic and phylogenetic beta diversity indices significantly increased with the spatial distance and difference in mean annual temperature between communities; that taxonomic beta diversity and MNTD were most strongly influenced by spatial distance, whereas MPD was equally influenced by spatial distance and mean annual temperature difference between communities; and that only 11–13% of the variance in beta diversity was explained by the spatial distance and mean annual temperature difference between communities. These results highlight the effects of niche and dispersal limitations on beta diversity, and suggest that dispersal limitation may play a greater role than habitat differences between plant community locations. Additionally, human disturbances may greatly impact species composition along the dry-hot valley of the Yuanjiang River.

关 键 词：群落构建 谱系beta多样性 生态位 扩散限制 人类干扰 

分 类 号：Q948[生物学—植物学]