Vegetation Traits and Soil Properties in Response to Utilization Patterns of Grassland in Hulun Buir City, Inner Mongolia, China

Numerous studies have focused on vegetation traits and soil properties in grassland, few of which concerned about effects of human utilization patterns on grassland yet. Thus, this study hypothesized that human disturbance(e.g., grazing, mowing and fencing) triggered significant variation of biomass partitioning and carbon reallocation. Besides, there existed some differences of species diversity and soil fertility. To address these hypotheses of grassland with diverse utilization patterns in Hulun Buir City, Inner Mongolia, China, we sampled in situ about aboveground biomass(AGB) and belowground biomass(BGB) to evaluate their biomass allocation. Species diversity and soil properties were also investigated. Subsequently, we discussed the relationship of species diversity with environmental conditions, using data collected from 23 sites during the ecological project period of Returning Grazing Lands to Grasslands(RGLG) program. The results were as follows: 1) both AGB and BGB were lower on grazing regime than those on fencing and mowing, but the ratio of root-to-shoot(R/S) was higher on grazing regime than the other two utilization patterns; 2) neither of evenness and Simpson Index was different significantly among all grassland utilization patterns in desert, typical, and meadow grassland at 0.05. In meadow grassland, species richness of fencing pattern was significantly higher than that of grazing pattern(p < 0.05); 3) both of soil organic carbon content and soil available phosphorous content were increased significantly on fencing pattern than grazing pattern(p < 0.05) in desert grassland, and mowing patterns increased the soil nutrients(soil organic carbon, soil total phosphorous, soil available phosphorous, and soil total nitrogen) significantly compared with grazing patterns(p < 0.05) in typical grassland. However, there were no significant differences among utilization patterns in meadow grassland. In conclusion, both of AGB and BGB were increased significantly by fencing. Moreover, species diversity and soil nutrients can be promoted via mowing and fencing. This study suggested that implementation of Ecological Project played a positive role in sustainable grassland utilization of Hulun Buir City and a strong positive influence on the entire temperate grassland.

Comparison of ecosystem services provided by grasslands with different utilization patterns in China's Inner Mongolia Autonomous Region

Although several previous studies in Inner Mongolia examined the effects of ecological conservation on the delivery of ecosystem services, they were often limited in scope（few ecosystem services were assessed） and often suffered from confounding by spatial variation. In this study, we examined the impact of conservation measures（changes in grassland utilization patterns） on the provision of selected ecosystem services in three types of grasslands（meadow steppe in Hulun Buir, typical steppe in Xilin Gol, and semi-desert steppe in Ordos） in Inner Mongolia. We examined five utilization patterns： no use（natural grasslands）, light use, moderate use, intensive use, and recovery sites（degraded sites protected from further use）. Through household surveys and vegetation and soil surveys, we measured the differences in ecosystem services among the different grassland utilization patterns. We also identified spatial factors that confounded the quantification of ecosystem services in different types of grasslands. We found that light use generally provided high levels of ecosystem services in meadow steppe and typical steppe, with the main differences in the supporting ecosystem services. Surprisingly, we found no consistently positive impacts of strict conservation activities across the sites, since the results varied spatially and with respect to differences in the land-use patterns. Our study suggests that appropriate grassland utilization patterns can enhance the supply of ecosystem services and reduce negative effects on both household livelihoods and the environment.