THE EFFECTS OF GRAZING INTENSITY ON LIGHT CHESTNUT SOIL MOISTURE,NUTRIENTS AND BIOMASS OF DESERT STEPPE

This is a comparison study on the effect of grazing intensity on soil moisture,nutrients and biomass of desert-steppe.Results show that under four different grazing treatments,surface soil moisture roughly shows: CK MG LG HG.While the deeper soil moisture presents the opposite effect.Soil nutrient content of mild(LG) treatment is significantly higher than the controlled zone(CK),moderately(MG) and severe grazing intensity(HG).Along with the increase of grazing intensity,biomass of plant communities declined obviously,specially,the biomass and its proportion of the dominant species and weeds.LG has trivial effect on the plant biomass.There are positive correlations between different soil factors and with biomass.And the correlation between organic matter and biomass is extremely significant.The result suggests that fence enclosure and moderate grazing is good for the conservation on soil moisture,fertility and for the increase biomass.