Abstract: As the primary mode of grassland utilization, settled grazing makes the piospheres widespread in arid and semiarid grasslands of China. During the end of May to early June, 2014, radiating from a watering point, 8 sampling transects were established at a set distance gradient of 50, 100, 200, 400, 800 and 1200 m following 8 orientations in Junggar basin of Xinjiang, China. The effects of piosphere were studied by analyzing the composition, species importance value, species richness, vegetation cover, height and aboveground biomass of the plant community, aiming to provide scientific basis for the restoration and sustainable management of the desert steppe. The results showed that, with the decrease of distance from the watering point, the grazing intensity increased, and the community characteristics varied significantly. Palatable Seriphidium borotalense is more abundant and dominant in areas distant from watering point, and the highly disturbed area  adjacent to watering point was dominated by annuals and poisonous Peganum harmala. The species richness of the community including perennials and annuals increased with decreasing distance from the watering point, while the vegetation cover decreased, which was notably driven by S. borotalense cover. The flourish of annual plants and poisonous P. harmala in the vicinity of the watering point indicated the degradation of the plant community approaching to the watering point. The implementation of the nomadic settlement project may produce more piospheres, which may accelerate the degradation process of the desert steppe.

Key words: trophic niche, feeding ecology, Conger myriaster, diet composition, food web]Laoshan Bay