Effect of Grazing Intensity on Root Biomass of Stipa grandis

Root biomass of Stipa grandis under different grazing intensity was measured for detecting the effect of grazing intensity on root biomass during the growing season.Results showed that the root biomass in different months under the same grazing intensity is significantly different(P0.05).The 0~30cm root biomass shows a N shape which signifies a July increase,then reduces in August,followed by a second flush in October.The root biomass of Stipa grandis has Significant differences(P0.05) in different grazing intensities under the same month.Compared with the no grazing treatment,moderate grazing intensity increases the root biomass 0.35%～16.52% from May to August.Root biomass reaches its lowest at highest grazing intensity.The root biomass forms a T-shape as roots grow deeper in soil.