Abstract: Fertilization and reseeding are currently main restoration methods for degraded grasslands. Clarifying the impacts of fertilization and reseeding on the stability of plant communities and the interspecific relationship in alpine meadows is of great significance for grassland restoration. In this study， after applying organic fertilizer and reseeding in the alpine meadows of Maqu County， the structure and composition of plant communities were investigated. The Euclidean distance was used to evaluate the community stability， and methods such as the Levins method， variance ratio method， and Pearson correlation test were employed to comprehensively analyze the ecological niches and interspecific relationships of main species within the study area. The results showed that from 2022 to 2024， the stability of plant communities in the alpine meadows decreased year by year. After fertilization and reseeding， the increase in the Euclidean distance was 7% lower than the control， significantly reducing the declining rate of community stability （P<0.05）. After fertilization and reseeding， the proportion of Gramineae and Cyperaceae increased by 122.9% and 73.7%， respectively， and the community stability and the proportion of the biomass of forbs rebounded in the third year. After fertilization and reseeding， the ecological niche breadth of main Gramineae increased， while the forbs decreased. The values of ecological niche overlap among species increased， the degree of interspecific association rose， and the anti-interference ability of the community enhanced. In conclusion， the measures of fertilization and reseeding had a positive effect on restoring the degraded alpine grasslands and maintaining community stability within three years of restoration. However， the succession process of plant community was not a one-way improvement， and measures needed to be taken in the later stage to delay the rebound of stability.

Key words: Reseeding, Organic fertilizer, Community stability, Ecological niche, Interspecific associations

摘要： 施肥补播是当前退化草地主要修复手段。明晰施肥补播对高寒草甸植物群落稳定性及其种间关系的影响，对草地修复具有重要意义。本研究在玛曲县施用有机肥和补播的高寒草甸调查了植物群落结构和组成，利用欧氏距离评价群落稳定性，运用Levins法、方差比率法和Pearson相关性检验等方法，综合分析研究区域内主要物种的生态位和种间关系。结果表明：2022—2024年高寒草甸植物群落稳定性逐年下降，施肥补播后欧氏距离增幅较其对照低7%，显著降低了群落稳定性下降速率（P<0.05），施肥补播后禾草科和莎草科占比提高122.9%和73.7%，第三年群落稳定性增幅和杂类草生物量占比回升；施肥补播后主要禾本科植物生态位宽度增加，杂类草生态位宽度降低，物种生态位重叠值增加，种间联结度升高，群落抗干扰能力增强。综上，施肥补播措施在修复3年内对退化高寒草地恢复和维持群落稳定性有积极作用，植物群落的演替过程并非单向的改善，后期需采取措施延缓稳定性反弹。

关键词: 补播, 有机肥, 群落稳定性, 生态位, 种间联结