Research On Soil Erosion Of Alkaline Sloping Land During Precipitation

Soil erosion is the main reason for the degradation and loss of land resource which is the base for human beings’existence and is becoming, which is also one of the most serious challenges faced by the human living environment recently. Most soil in arid and semi arid regions belongs to erodible soil. Therefore, soil erosion is one of the most important limiting factors which restrict the sustainable development of economy and society in the loess plateau region.In this experiment, the effect on the infiltration and erosion of soil with different rainfall intensity(50mm/h、100mm/h),different slope (5°15°、25°)and different soil (exchangeable sodium percentage (ESP) are2.4and25respectively) were studied. The indoor artificial rainfall simulation methods were adopted in the experiment which use slope adjustable steel trough and loess in Yangling district. The result shows:1) In the same slope and soil, the cumulative runoff, infiltration and erosion of sloping land soil increase with the increase of rainfall intensity. The runoff in different rainfall period increase with the increase of time, while the infiltration rates decrease with the increase of time and finally achieve stability. 2) in the same rainfall intensity and soil, when the slope is less than15degrees, the runoff and erosion increase with the increase of the slope, when the slope is25degrees, the runoff and erosion decrease with the increase of the slope, the size of the critical slope depends on the change of rainfall and soil law.3) in the same rainfall intensity and slope, the cumulative runoff of alkali soil is bigger than that of non alkali soil, but the total infiltration and erosion of alkali soil is smaller than non alkali soil.The study contribute to the improvement of management level of sloping fields and reasonable formulation of management policy and law of non arable upland and supply basic data for prediction model of soil erosion. In order to understand the soil erosion mechanism further, however, it is necessary to study soil with different initial water content in different rainfall intensity, raindrop diameter and duration of rainfall.