Abstract:To explore how grazing affects grassland ecosystem,we studied the relationship of grassland community and soil characteristics in both grazing and restgrazing grasslands. The object of this study was to determine the changes of the relationships between species diversity and productivity, soil characteristics (soil organic carbon, nitrogen contents) and biomass in the grazing grassland. The results showed that: (1) the above biomass and litter biomass were decreased significantly by livestock ingestion. From the perspective of functional groups, the biomass of grasses in grazing grassland was 19.77% more than in restgrazing grassland. However, the biomass of forbs and legumes in grazing grassland were 31.09% and 23.42% less than in restgrazing grassland. The ingested strategies of livestock were changed in the communities with different species diversity. Community productivity was decreased significantly by ingesting enormous grasses, which is the dominant species in community, in the communities with lower species diversity. (2) When diversity was less than 1.3, the productivity of restgrazing grassland is higher than that of grazing grassland, but when diversity was more than 1.3, community productivity showed a contrary trend. (3) Results from Canonical Correlation Analysis (CCA) showed that livestock influenced soil carbon and nitrogen contents through changing aboveground biomass, litter biomass and soil bulk density. (4) Abovebiomass was significantly influenced by livestock in the lower aboveground biomass community (<100 g·m-2), so the soil organic carbon and total nitrogen contents responding to the same aboveground biomass were higher in restgrazing grassland than that in grazing grassland. However, there was a contrary trend in the high abovebiomass grassland (>100 g·m-2). (5) When belowground biomass was less than 1 200 g·m-2, soil organic carbon and total nitrogen contents were higher in grazing grassland than that in restgrazing grassland, but when belowground biomass was more than 1 200 g·m-2, soil organic carbon and total nitrogen contents showed a contrary trend. We suggested that the scientific and reasonable grazing and management strategies should be conducted to coordinate livestock and plant community. Both economic benefits and ecological benefits should be considered, when achieving sustainable development in grassland grazing ecosystem.