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植物群落特征和生存状态变化能够反映植物群落内种间关系和演替进程。本研究以青海海北地区高寒草甸的冷季放牧场为研究对象，分析比较了禁牧封育(CK，禁牧)、轻度放牧(LG，4.5只羊·hm−2)、中度放牧(MG，7.5只羊·hm−2)和重度放牧(HG，15只羊·hm−2) 4种放牧压力对植物群落特征及各功能群代表性植物生存状态指数的影响。结果表明：1)禾本科的重要值在轻度放牧时最大，莎草科的重要值在禁牧样地中最大，杂草类植物的重要值在重度放牧样地中最大。2) Shannon-Wiener多样性指数、Simpson优势度指数、Patrick丰富度指数随着放牧强度的增加均呈增加趋势。3)轻度放牧样地中垂穗披碱草(Elymus nutans)和山地早熟禾(Poa orinosa)的生存状态指数最高，禁牧样地中矮生嵩草(Kobresia humilis)和钝苞雪莲(Saussurea nigrescens)的生存状态指数最高，但随着放牧强度的增加，钝苞雪莲(Saussurea nigrescens)的生存状态指数也随之增加。研究结果表明放牧强度增加能提高高寒草甸群落多样性，禾草类生存状态和在群落中的优势地位下降，杂草类生存状态和在群落中的优势地位上升，草地质量下降。“,”Changes in plant community characteristics and vegetation living states may reflect interspecific relationships and succession processes within plant communities. This study used the cold-season grazing grassland of the alpine meadow in Haibei, Qinghai Province as its research object to analyze and compare the characteristics of the vegetation community and the plant living state resulting from four different grazing management practices, including grazing prohibition (CK, no grazing), light grazing (LG, 4.5 sheep·ha−1), moderate grazing (MG, 7.5 sheep·ha−1), and heavy grazing (HG, 15 sheep·ha−1). The results showed that 1) Gramineae, Cyperaceae, and weeds had the highest importance value indexes in LG, CK, and HG plots, respectively; 2) the Shannon-Wiener index, Simpson index, and Patrick richness showed an increasing trend with increasing grazing intensity; and 3) Elymus nutans and Poa orinosa had the highest survival status indexes in the LG plots, whereas Kobresia humilis and Saussurea nigrescens had the highest survival status indexes in the CK plots. Noteworthy, with the increase in grazing intensity, the survival status index of Saussurea nigrescens also increased. The results of this study showed that, as the grazing intensity increased, the community diversity of the alpine meadows and the survival status and dominant position of weeds in the community increased; in contrast, the survival status and dominant position of grasses in the community and the quality of the grassland decreased.