青海海北不同退化程度矮嵩草植物群落特征研究

目的]揭示高山草甸生态系统结构、功能,为高山草甸草场的开发利用、科学管理和草地畜牧业可持续发展提供科学依据。方法]以青海海北原生矮嵩草（Kobresia hum ilis）植物群落（Ⅰ）、退化矮嵩草植物群落（Ⅱ）为研究对象,分析植物群落结构特征;同时,对矮嵩草群落生物量及多样性指数,丰富度指数进行相关性分析。结果]群落（Ⅰ）的物种丰富度、生物多样性指数、生物量（分别为42、3.531、3 553.1 g/m2）,均高于群落（Ⅱ）（分别为37、2.270、3 391.1 g/m2）;群落总生物量与物种丰富度在0.01水平上呈极显著正相关,多样性指数与地上生物量、物种丰富度在0.01水平上呈极显著正相关。结论]群落（Ⅰ）结构合理,地表植被覆盖度大,对该地区生物多样性、生态系统功能起重要维护功能。

Characteristics of Kobresia humilis Community Structure at Different Degraded Levels in Northern Qinghai

Objective] To reveal structure and function of alpine meadow ecosystem and thus to provide a scientific basis for development,utilization and scientific management of alpine meadow pasture as well as sustainable development of animal husbandry.Method] Characteristics of Kobresia humilis communities with primary vegetation(community I) and degraded vegetation(community II) were analyzed.Result] Species richness,biodiversity indices and biomass of the community I were respectively 42,3.531 and 3 553.1 g/m2,which were respectively higher than those of the community II(37,2.270 and 3 391.1 g/m2).Correlation analysis show that community biomass was correlated positively with the richness index(P<0.01),and biodiversity index was correlated positively with aboveground biomass and the richness index(P<0.01).Conclusion] The Kobresia humilis community I has reasonable structure and large coverage of ground vegetation,which play an important role in maintenance of biodiversity and ecosystem function.