Soil Properties And Vegetation Characteristics Characterization And Judgment Of Different Coverage Xilamuren Desert Grassland

in recent years, with the climate change and human disturbance, agriculture and animal husbandry in northern China is located in the staggered with the Xilamuren desert steppe showed different degradation degrees.especially, the degradation of vegetation and soil is most prominent. In this paper, the soil and water conservation ecological monitoring center of the Ministry of water resources is selected based on the TM image, In different vegetation coverage gradient, setting a plot, analysis of the characteristics of the vegetation community and soil physicochemical properties (0-40cm). The main conclusions are as follows:(1)With the decrease of vegetation coverage, plant height, plant density and aboveground biomass were significantly decreased. In 60% of vegetation coverage is bounded, main vegetation coverage have Leymus chinensis and Siipa krylovii+ Heteropappus Baby Flower+Potentilla bifurca, the dominant species is Leymus chinensis., in low and medium coverage sample plots (40%), the main vegetation have Stipa krylovii+Artemisia frigida+bifid Potentilla+Stellera chamaejasme, the dominant species is Stipa krylovii. Low coverage (20%) into the main vegetation of Stipa krylovii+Artemisia frigida+Asian thyme, the dominant species for degradation indicator plants is Artemisia frigida.(2) With the vegetation coverage decreased, species diversity index and richness index were increased first and then decreased; species distribution evenness index showed a decreasing trend, grassland degradation become more and more serious.(3)Mechanical composition and its influence depth is different under different coverage, With the decrease of coverag e, gravel and sand content increased, silt and clay decreased, the fractal dimension of soil and gravel content was significantly negatively related with powder and clay grain content was significantly positively correlated and highly significant positive correlation. Vegetation cover affects content of soil organic matter, The higher the coverage, the higher the content of organic matter.(4)Soil mechanical composition, bulk density and nutrient index showed a significant negative correlation (P< 0.01), and the vegetation community structure and a diversity index showed a significant negative correlation (P<0.05); soil porosity, water content and soil nutrient index and vegetation biomass, plant density showed significant positive correlation (P<0.01). The main influencing factors of vegetation growth include mechanical composition, soil moisture content, organic matter, available phosphorus and so on.