How Grazing, Enclosure, and Mowing Intensities Shape Vegetation–Soil–Microbe Dynamics of Qinghai–Tibet Plateau Grasslands: Insights for Spatially Differentiated Integrated Management

Grasslands provide essential forage, fuel, and ecosystem services, underpinning regional livestock husbandry and ecological integrity. However, improper utilization drives structural degradation and functional decline of the vegetation–soil–microbe system, particularly on the ecologically sensitive and fragile Qinghai–Tibet Plateau (QTP). The differential impacts of diverse utilization practices on QTP grasslands remain inadequately understood, limiting scientific support for differentiated sustainable management. To address this, we conducted a comprehensive meta-analysis to clarify effects of grazing, enclosure, and mowing on QTP grasslands, integrating studies from Web of Science, Google Scholar, and CNKI. We constructed disturbance intensity indicators to quantify utilization pressure and used multiple ecological metrics to characterize heterogeneous responses of the vegetation–soil–microbe system. Moderate grazing enhanced vegetation coverage, biomass, diversity, soil total phosphorus, and organic matter; high-intensity grazing reduced vegetation traits, soil bulk density, moisture, nutrients, and microbial biomass/diversity, while increasing soil pH. Early enclosure mitigated anthropogenic disturbance to improve grassland functions, but long-term enclosure exacerbated nutrient/moisture competition, lowering vegetation biomass/diversity and degrading soil properties. Moderate mowing improved vegetation communities by suppressing dominant species overexpansion; excessive mowing caused vegetation homogenization, soil carbon loss, and microbial destabilization. Impacts showed environmental heterogeneity linked to climate, soil, vegetation type, and elevation. In humid and fertile alpine meadows, moderate grazing more effectively promoted vegetation diversity and soil nutrient cycling, while in arid and nutrient-poor desert grasslands, even light grazing led to visible declines in vegetation coverage and soil moisture. Low-elevation alpine grasslands exhibited stronger positive responses to moderate grazing, whereas high-elevation alpine desert grasslands showed high vulnerability even to light grazing. Based on these mechanisms, regionally tailored strategies integrating multiple practices are required to balance ecological conservation and livestock production, promoting QTP grassland sustainability. In future research, we will strengthen quantitative exploration of how specific environmental factors regulate the magnitude and direction of grassland ecosystem responses to grazing, enclosure, and mowing, thereby providing more precise scientific basis for differentiated grassland management.