Effect of grazing on greenhouse gases in grassland ecosystems

Grazing affects grassland greenhouse gas (GHG) emissions by changing the physical and chemical properties of soil, such as the soil water content, porosity, and microbe and organic matter contents. Respiration of plant roots, soil microbial activities, and various physical, chemical, and biological functions in grassland ecosystems are the main sources of GHGs. Based on the mechanism and function of GHG emissions in grassland ecosystems, this paper reviews the GHG emissions in grassland ecosystems from grazing management, grazing intensity, and grazing animals. The effects of grazing on GHGs in grassland ecosystems, the focus and direction of research prospects, and a summary of the measures taken in different ecosystems to reduce GHGs are discussed in this paper.