Abstract: The purpose of this study was to explore the relationship between plant diversity and ecosystem multifunctionality. Taking Qinghai Delingha Gahai National Wetland Park as the object， K-means clustering method was used to divide three water and salt gradients of high， medium and low， and the changes of environmental factors， plant species diversity， functional diversity and ecosystem multifunctionality were analyzed. The results showed that there were significant differences in plant diversity index and functional richness index under three water and salt gradients. The value of low water and low salt environment was the largest， and the value of high water and high salt environment was the smallest. The correlation between plant diversity and functional diversity decreased with the decrease of water and salt gradient. Among the abiotic factors， soil conductivity played a decisive role in the multifunctionality of the ecosystem， and soil moisture content indirectlyaffects it. Among the biological factors， the effect of functional diversity on ecosystem multifunctionality is greater than that of species diversity. In summary， the water-salt gradient significantly affects plant diversity and ecosystem function， which is of great significance to the protection of Gahai wetland.

Key words: Gahai Lake, Water-salt gradient, Plant diversity, Plant community succession, Ecosystem multifunctionality

摘要： 本研究旨在探讨植物多样性与生态系统多功能性之间的关系，以青海德令哈尕海国家湿地公园为对象，采用K均值聚类法划分高、中、低三个水盐梯度，分析环境因子、植物物种多样性、功能多样性及生态系统多功能性的变化规律。结果显示：植物物种多样性指数和功能丰富度指数在三种水盐梯度下均存在显著差异，低水低盐环境值最大，高水高盐环境值最小；植物多样性与功能多样性的相关性随水盐梯度降低而减弱；非生物因子中，土壤电导率对生态系统多功能性起决定作用，土壤含水率间接影响；生物因子中，功能多样性对生态系统多功能性的作用大于物种多样性。综上，水盐梯度显著影响植物多样性和生态系统功能，对尕海湿地保护具有重要意义。

关键词: 尕海湖, 水盐梯度, 植物多样性, 植物群落演替, 生态系统多功能性