Grazing maintains ecosystem stability by enhancing interspecific correlations in grassland vegetation

Reseeding is a key restoration strategy for degraded alpine grasslands. Understanding the impact of grazing on reseeded grasslands is essential for guiding their scientific management and sustainable utilization. In this study, we investigated the effects of moderate grazing and enclosure on vegetation community characteristics and ecological niche dynamics in a replanted alpine grassland. The results showed thatIn contrast to the enclosure, grazing significantly decreased belowground biomass and litter accumulation, and it significantly increased the plants’ Shannon-Wiener, dominance, evenness, and richness indices (P < 0.05).. Grazing increased the importance value of weed functional groups. The average connectivity and average clustering coefficient of the plant co-occurrence network were significantly higher under grazing than under enclosure. Niche width and niche overlap of plant communities were greater under grazing management, with Gramineae and forbs predominantly occupying available resources. In conclusion, cold-season grazing in replanted alpine grasslands enhanced plant diversity and productivity, promoted niche differentiation among species, and contributed to greater community stability. These findings provide a theoretical basis for the rational management and sustainable use of replanted alpine grasslands in the Qilian Mountains.