Nest circle distance affects plant community structure and spatial distribution of soil nutrients in alpine meadows

The effects of grazing intensity on grassland vegetation community structure and soil physicochemical properties has been extensively studied. However, very few studies have focused on how grazing intensity affects grassland plant community structure, soil physicochemical properties, soil microorganisms, and soil enzyme activity. This study investigated the effects of circular distance on grassland plant community structure, soil physicochemical properties, soil microorganisms, and soil enzyme activity in the winter pasture of the Gannan Alpine Meadow with a circle as the center and a 3 km radius area defined as heavy grazing (HG), a 6 km radius area defined as moderate grazing (MG), and a 9 km radius defined as light grazing (LG). The results showed that the plant community structures changed significantly and the community height, coverage, and species richness decreased with an increase in grazing intensity (P < 0.05). Moreover, the response of soil physical and chemical property indicators to the pit distance varied. The total potassium and soluble organic nitrogen content significantly decreased with an increase in nest distance (P < 0.05), while the carbon and nitrogen content in microbial biomass was significantly increased with an increase in litter distance (P < 0.05). 4) The nest distance significantly impacts soil enzyme activity. The N-acetyl-beta-D-glucosaminidaseo, peroxidase, and polyphenol oxidase levels decreased with increasing ring distance (P < 0.05). These findings indicate that the nest circle distance can affect grassland plant community structure and ecosystem functioning and partially reflects grazing intensity. These results also provide theoretical support for grazing management and sustainable grassland utilization.