| Inner Mongolia of China and Mongolia both hold the main body of Mongolian Plateau. The climate, the basic structure of grassland in the two countries are quite similar. So it′s of great significance to engage a com comparative study on the influence that the two different grazing systems and grassland management policies have on the soil and plant communities .The result shows that:1. The comparison of soil bulk density and hardness with different grazing patterns: Grazing settlement>Rotational grazing>Nomadic grazing; the comparison of soil moisture content and porosity of the results: Nomadic grazing>Rotational grazing>Grazing settlement.2. The sand of the soil with different grazing patterns: Grazing settlement >Rotational grazing>Nomadic grazing. The silt content in nomadic areas are higher than that in grazing settlement areas and rotational areas .The latter have no significant differences in the content of silt and fine silt. The clay content in summer pastures: Nomadic grazing>Grazing settlement>Rotational grazing. The clay content in winter pastures: Nomadic grazing>Rotational grazing>Grazing settlement.3. The soil organic matter, the total Nitrogen, the available Nitrogen and the total Phosphorus in nomadic areas are significantly higher than that in the other two areas. The rotation area's is higher than grazing settlement area's .The available Phosphorus and the available Potassium in nomadic areas is higher than that in the other two areas. Except the 0-10cm soil layers in winter pastures, the contents in the other soil layers in rotation areas are higher than those in grazing settlement areas. The results of this comparison for PH value and the total Potassium: Grazing settlement>Rotational grazing>Nomadic grazing; the Conductivity: nomadic>Rotational grazing>Grazing settlement.4. The importance value of Stipa krylovii in nomadic areas is45.5,followed by Leymus chinensis (25.5).The third is Allium polyrhizum(24.5).Stipa kryovii has a dominant position in the composition of the community.In rotational areas,the important values of the top three plants are: leymus chinensis (59.5), Allium polyrhizum (45.6) and Convolvulus ammannii (29.0).There are also annual indicative species for degradation in the communities, such as Eragrostis pilosa and yellow Artemisia.Among them,the importantce value of Eragrostis pilosa goes the fourth..In grazing settlement areas,the plants with importance value of the top three are: Astragalus white flower,Cleistogenes squarrosa and Chatham Lepidium,some indicative species for serious degradation like Salsola collina also appear in the communities.5. The results of this comparison for Jianqun type species and perennial weeds about the height, coverage, importance value, frequency, performance rate and weight: Nomadic grazing> Rotational grazing> Grazing settlement. The height and coverage of perennial weeds in rotation grazing areas are higher than that in grazing settlement areas. The height, frequency and weight results of this comparison for Annual weeds category: Grazing settlement> Rotational grazing> Nomadic grazing. The importance value and performance rate: Grazing settlement> Rotational grazing> Nomadic grazing. Coverage: Rotational grazing> Grazing settlement> Nomadic grazing.6. The analysis results of the physical and chemical properties of soil and characteristics of plant communities under different grazing patterns: soil bulk density,hardness,sand content,PH value and the total Potassium have negative correlation with plant community characteristics while soil moisture,porosity,organic matter,the total Nitrogen,the available Nitrogen, the total Phosphorus,the available Phosphorus and electrical conductivity have positive correlation with plant community characteristics.7. The degree of grassland degradation under different grazing patterns: it's the most serious in grazing settlement areas, followed by rotational grazing areas and nomadic grazing areas.
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