The Impact Of Soil And Water Conservation Engineering Measures On The Slope Heteroheneity Of Granite Red Soil

Granite red soil is the zonal soil in south china, soil and water loss is very serious because of the effect of natural and human factors. Slope engineering is an important measure to the region management of soil and water conservation, with soil and water conservation after the measure finished, the distribution of soil and water in the slope been changed, research this variation is not only beneficial to evaluate the measures, but also have great significance to discusses of vegetation restoration and reasonable layout. This study choose a typical granite red soil slope as research object, observe the soil property of fish-scale, level-terrace, level-trench and control plot form the different slope position and measure position, analysis the different of soil spatial heterogeneity in each plot, provide the theoretical basis to further study on different measures of soil and water conservation and vegetation provides, and get conclusions as:(1) Three kinds of slope engineering measures can reduce soil and water erosion effectively. In the effect of sediment reduction, level-trench (18.89%)> fish-scale (15.23%)> anti-slope (7.45%), in the effect of runoff reduction, level-trench (37.73%)>anti-slope27.86%)>fish-scale (21.90%), level-trench has best effect on reducing sediment and runoff.(2) Three kinds of slope engineering measure change the spatial heterogeneity of soil properties. Spatial distribution of sediment erosion in quantity, soil physical, nutrient content and water content are characterized by level-trench> fish-scale> anti-slope. Silt sedimentation decrease gradually from top to toe, soil property in good condition on central slope, nutrient enrichment in this area. Compare with control district, the characteristics of sediment has large change in anti-slope, upside surface is the main sedimentation region, soil physical properties and moisture distribution showed no difference. Measure internal is the main water-rich and nutrient-rich area in level-trench, heterogeneous distribution measures mainly reflects in the measures of external and internal differences. (3) Different measures and slope position have different role in factor to the distribution of heterogeneity, spatial distribution of mud sediment silting and soil physical property are related to measures and slope positions, there are great differents between different measures and different slope positions, the spatial distribution of water only have differences in the measure scale, moisture content in slope measures are higher than outside in each slope position.(4) Slow down the process of the rainfall distribution on the slope surface play a main mechanism of soil and water conservation benefit, this slow process determines the effect of soil and water conservation in measures. Because of the ridge measures in level-trench, the runoff flow been cut off thoroughly and the process of rainfall been slowed down swingeing, therefore the soil and water conservation benefits is better than others measure.(5) According to the spatial distribution of soil properties, put forward the layout of the slope engineering measures and vegetation measures which promote vegetation restoration as the center, select the tree planting which has economic benefits in the central area of fish-scale, the bottom of anti-slope and the top area of level-trench, three measures all need to send up the excavation in top area, at the same time, according to the comparison of three measures of soil and water conservation benefit, this study suggests to select level trench as the most suitable slope engineering measures in study area or the area under similar conditions.