Impacts of grazing intensity on soil properties and carbon content in Xilamuren Grassland

Grazing, one of the most widely used methods in grasslands, involves livestock trampling, foraging, and manure inputs, which influence soil organic carbon fraction content by influencing vegetation community structure, soil nutrients, and enzyme activities, significantly affecting grassland carbon balance. This study investigated the effects of different grazing intensities on vegetation biomass and soil properties. An increase in grazing intensity significantly reduced vegetation biomass, whereas the organic carbon content of plants showed a trend of decreasing and then increasing. Grazing intensity significantly affected soil nutrient and enzyme activity, with effects modulated by soil depth. For example, the TN content in the top soil layer of moderate grazing (MG) and heavy grazing (HG) significantly decreased by 29.99 % and 28.47 %, respectively, compared with CK, and the TN content in the 10–20 cm soil layer of HG significantly decreased by 30.46 % compared with CK. Quick-acting potassium content in the 0–10 and 10–20 cm soil layers of HG significantly increased compared with CK by 42.61 % and 56.90 %, respectively. Light grazing and MG β-cellulase activities were significantly increased by 16.85 % and 11.04 %, respectively, compared with CK. This study explores the regulatory mechanisms of grazing intensity on vegetation - soil systems from multiple dimensions, clarifies the key factors affecting carbon storage and the pathways of carbon transformation, and offers a theoretical basis for managing grazing strategies.