To elucidate the mechanism by which grazing intensity affects ecosystem multifunctionality （EMF） in alpine grasslands. In this study， the alpine grassland of Qinghai Lake was selected as the study area. Four treatments were set up， including grazing prohibition， light grazing， moderate grazing and heavy grazing. The effects of grazing intensity on plant functional traits， soil factors and ecosystem multifunctionality （EMF） were analyzed. The results showed that grazing intensity significantly changed plant community traits （P<0.05）. As grazing intensity increased， community-weighted height and leaf area decreased， while leaf nitrogen and phosphorus contents increased. Aboveground and belowground biomass significantly declined under heavy grazing （P<0.05）. The soil exhibited a decoupling character of nitrogen and phosphorus， with nitrate-nitrogen and ammonium-nitrogen decreasing while total phosphorus and available phosphorus accumulated. Moderate grazing had the most pronounced effects on soil moisture and pH （P<0.05）. The functional dispersion index increased with grazing intensity， and EMF peaked under moderate grazing. The structural equation model showed that grazing indirectly affected ecosystem multifunctionality （EMF） by regulating plant traits， functional dispersion index， and soil quality index （SQI）， with soil quality being the key driving factor. This study elucidated the intrinsic mechanism by which grazing intensities influences EMF through the coordination of plant functional strategies and soil nutrient patterns， providing a theoretical basis for the scientific management of alpine grasslands around Qinghai Lake.

Grazing intensity  /  Plant functional traits  /  Soil factors  /  Functional diversity  /  Ecosystem multifunctionality