Soil Fertility Quality Evaluation Of Different Slope Of Loess Hilly Areas In Western Shanxi

Shanxi west loess area current slope land utilization present situation, shows the different combinations of land use along the slope surface, mainly composed of forest land, grassland and farmland, including for farmland shelterbelt forest land, grassland to farmland of weeds in farmland. In this paper, by studying the different land use combinations of side slope soil fertility quality differences discussed, from the Angle of the soil fertility quality slope land use mode choice for the future reference.Research choose Zhong Yang Xian loess hilly area in Shanxi Province4class has lasted for more than ten years of land use of various combinations of slope type as the research object.4types of slope, from upper slope to lower slope land use ways are:"forest-farmland-forest","farmland-grass-forest","forest-grass-farmland" and "farmland-forest-grass". Through the sample to setting and soil samples, the indoor test of soil physical and chemical11indexes determination, including:bulk density, porosity, clay content, moisture content, organic matter, total nitrogen, available nitrogen, total phosphorus, available phosphorus, total potassium and available potassium. With different types of slope soil fertility quality as the research object, the main conclusions are as follows:1) The four types of slope soil bulk density, porosity, clay content, moisture content and organic matter content affected by land use types significantly. Forest land surface soil physical property is superior to the grassland and farmland. Clay content, total nitrogen, available nitrogen and total potassium content are presented to the slope of a enrichment phenomenon, total phosphorus content affected by land use type and the slope position is not significant, effective phosphorus is affected by the slope position, showing a slope in the upper to under a trend, will affect significantly effective potassium content, performance for effective potassium content in the farmland is superior to grass and forest.2) There are four types of slope soil, single factor analysis results obvious differences show that the single index cannot reflect comprehensively the slope soil fertility quality, objective and accurate evaluation for soil fertility quality is based on the comprehensive analysis of soil physical and chemical indexes.3) Four types of slope surface soil fertility quality order from high to low was:D (farmland-forest-grass)> C (forest-grass-farmland)> B (farmland-grass-forest)> A (farmland-forest-forest), from the point of view of soil fertility quality, local should according to the actual situation, to promote land use combinations of "farmland-forest-grass" type slope, in order to reduce the slope of soil and water loss, improve the quality of soil fertility.