Changeable characteristics of three soil microbial groups underdifferent grazing intensities in Loess Plateau

An experiment was conducted to investigate the Changeable characteristics of three soil microbial groups at four grazing intensities (0,2.7,5.3 and 8.7 sheep/hm2) in Loess Plateau. The results of this study indicated that the quantities of microbial gradually reduced from 010 cm layer, 020 cm layer, to 2030 cm layer at each grazing intensities. Total number of microorganism was different under different grazing intensities in the same depth layer, indicating that the number was higher at no grazing and moderate grazing intensity, and the number was the highest at overgrazing in Loess Plateau. The quantities of microbial group was not different among grazing intensities, indicating that the highest number of fungi and bacteria were founded in September and the highest number of actinomycete were founded in November.