关键词: 放牧, 土壤有机碳, 草地, Meta分析, 中国

Abstract: The grassland soil carbon pool is rich in organic carbon storage and plays an important role in the global carbon cycle. Soil organic carbon (SOC), as the main storage form of carbon in the soil, is essential for regulating global climate. Grazing, as the most common grassland utilization pattern, affects the SOC content of grassland. However, the results of related research are inconsistent. The literature on the effects of grazing on SOC content in grasslands in China were comprehensively searched and the meta-analysis was used to carry out quantitative evaluation. The results showed that grazing significantly reduced SOC content by 20.78%. Under moderate and heavy grazing conditions, the SOC content of grassland decreased significantly by 14.62% and 45.5%, respectively, while light grazing had no significant effect on SOC content. Climatic factors (precipitation and temperature), environmental factors (elevation and soil depth), and management practices (grazing duration) affected the responses of grassland SOC content to grazing to varying degrees, respectively. This study quantitatively analyzed the effect of grazing on the SOC content of grasslands in China and provided scientific basis and theoretical references for grassland grazing management and responses to climate change.

Key words: Grazing, Soil organic carbon, Grassland, Meta-analysis, China