Response Of Vegetation And Soil Physical And Chemical Properties To Grazing Systems In Stipa Grandis Steppe

The characteristics of plant communities and soil physical and chemical properties based on family ranches were investigated in Stipa grandis steppe of Xilingol, Inner Mongolia from2009to2011. The main results were shown as follows:1. There was a trend that the height, coverage and density of Stipa grandis, Leymus chinensis and Cleistogenes aquarrosa of the rotational grazing area were higher than that in the continuous grazing area. The important values of Stipa grandis, Leymus chinensis and Cleistogenes aquarrosa in the rotational grazing area were higher than that in the continuous grazing area.2. The index of community β-diversity in the rotational grazing area was higher than that in the continuous grazing and CK areas when the sampling area was less than1/2m2and more than4m2. The Morisita-Horn similarity coefficients in the rotational grazing and CK areas were higher than that in the continuous grazing area.3. The above-ground standing crop of Stipa grandis, Leymus chinensis, Cleistogenes aquarrosa and community in the rotational grazing area were higher than that in the continuous area.4. The underground biomass declined with an increase of soil depth in each treatment. There was a trend that the underground biomass in the rotational grazing area was higher than that in the continuous grazing area. The underground biomass increased with the trend of distribution in surface soil, mainly concentrated in the0-30cm of soil layer. The upward trend of root movement in the CK area was lower than two grazing treatment areas.5. The content of crude fiber, crude fat and nitrogen-free extract of plants in the rotational grazing area were higher than that in the continuous grazing and CK areas.The content of crude protein of plants in the continuous area was higher than that in the rotational grazing area, which was same change trend in the two grazing treatment areas6. The soil moisture content in the rotational grazing and CK areas were higher than that in the continuous grazing area. The available nitrogen content in the rotational grazing area was higher than that in the continuous area. The P content in CK area was higher than that in the rotational and continuous grazing areas.