Abstract: To reveal the composition and interspecific relationship of plant communities in Lhasa River basin,the composition,diversity,interspecific association and ecological group of community species were analyzed using 100 herbaceous quadrats. The results showed that:(1) There are a total of 25 families,58 genera,and 90 species of plants in the study area. (2) There are significant differences in the dominant species of different types of wetlands,and Eleocharis valeculosa,Argentina anserina,Kobresia pygmaea are the main dominant species. (3) Jiama Wetland has the largest diversity index,followed by Jiangxia Wetland. (4) X² test,AC (connection coefficient),PC (percentage of co- occurrence),and Ф(point correlation coefficient) test indicated that the dominant species are not strongly interconnected and are relatively independent of each other. (5) The overall connectivity of Yarang Wetland showed significant negative correlation,and Tangjiaguo Wetland showed no significant correlation with Jiama Wetland,and the other two types showed significant positive correlation,indicating that the diversity of wetland plant communities in Yarang Wetland was small and the distribution of species was uneven,and the wetlands were in the unstable succession stage. (6) Based on the clustering analysis and interspecific association determination of the community,16 main species were divided into 3 ecological species groups. Based on the similarity in ecological habits of species within the same ecological species group and the ecological characteristics of species between different ecological species groups,important basic data and scientific guidance are provided for the vegetation restoration of wetland ecosystems in the study area.

Key words: Wetlands, Herbal communities, Species diversity, Interspecific connection, Ecological group

摘要： 为揭示拉萨河流域植物群落间的组成及种间关系。本研究利用100个草本层样方分析群落物种的组成、多样性、种间联结性及生态组。结果表明:(1)研究区植物共有25科58属90种。(2)不同类型的湿地优势种具有明显差异,具槽秆荸荠(Eleocharis valleculosa)、蕨麻(Argentina anserina)、高山嵩草(Kobresia pygmaea)为主要优势种。(3)甲玛湿地多样性指数最大,江夏湿地次之。(4)X²检验、AC(联结系数)、PC(共同出现百分率)和Ф(点相关系数)表明,优势种间联结性不强,各物种相对独立。(5)雅让湿地总体联结性呈显著负关联,塘嘎郭湿地与甲玛湿地总体联结性呈不显著关联,其他2种类型均为显著正关联,说明雅让湿地植物群落多样性较少且物种之间分布不均,湿地总体均处于不稳定演替阶段。(6)根据群落的聚类分析和种间联结测定的结果,把16个主要种划分为3个生态组。为研究区湿地生态系统植被恢复提供重要基础数据。

关键词: 湿地, 草本群落, 物种多样性, 种间联结性, 生态组