Soil Characteristics And Its Relationship With Landscape And Vegetation In The Cascade Ecosystem Of Horqin Sandy Land

Soil was an important material base of vegetation’s growth and vegetation was the main part of the windbreak and sand-fixation.The vegetation’s distribution and soil characteristics were inseparable. Due to microenvironmental changes of the different landscape conditions, the physicochemical properties of the soil was different, maybe affect the distribution of the vegetation in the area, which affect the diversity of species. The gradual change of soil characteristics will be useful to realize the influence of vegetable diversity, the condition of the sand dunes, and then analyze the distribution of vegetation diversity had the vital significance.With using statistical model and the canonical correspondence analysis, we studied the gradual change of soil characteristics and the correlation between species distribution and soil factors through careful investigation sampling and test analysis in Horqin sandy land. The results show that:(1)There was one positive correlation through sand content、silt content and clay content, there was the other positive correlation through capillary rise of moisture、 saturated soil moisture and field moisture in soil physical properties in Horqin sandy land, and the soil moisture is affected by soil texture and soil bulk density. In different ecological belt, the general result was soil moisture of meadow lands was highest, sandy dunes was lowest, farmland, forest land transition zone in the middle.(2)the pH was an important indicator of dividing soil type, effected by soil texture and climate, the result was sandy dunes was stabled around 7, the pH of farmland was alkaline, the alkalinity of meadow lands was highest. The result of electric conductivity and organic matter was the meadow> the transitional land> the sandy dunes.(3)The soil particle composition was analyzed in different ecological belt and landscape, the evolution law of soil grain level was the fractal dimension increased from the north and the south sand dune to the lake, the clay content was increased and the sand content was reduced.(4)The research results showed that the Margalef、Shannon-Weiner、Simpsonfenhaos index were the highest in the fixed dunes, they were the lowest in the meadows and the mobile dunes; the Pielou’s index、the vegetation covers and aboveground biomass were the the highest in the meadows, they were the lowest in the mobile dunes. The result of the Hill’s index showed the orders of species diversity was fixed dunes、semi-fixed dunes、 semi-mobile dunes、meadows、mobile dunes. The degree of influences of soil factors on vegetation distribution was pH>sand content>silt content>field moisture>capillary rise of moisture>saturated hydraulic conductivity>dry bulk density>particle fractal dimension>electric conductivity>organic matter>saturated soil moisture>natural moisture>clay content.