The Influence Of Different Slope, Bulk Density And Coverage On Hill Slope Soil Erosion And Infiltration

Through artificial simulation rainfall test, to study the relationship between runoff start time, runoff amount, runoff stop time, sediment yield, infiltration rate, rill erosion and slop, soil bulk density, straw coverage, besides the variation law of runoff amount, sediment yield and infiltration rate with time going. Then by analyzing the results:(1)Under conditions of some rainfall intensity, slop and straw coverage, runoff start time:5°>15°>10°, as the slop increasing, the average soil infiltration rate decreases, runoff amount increases, runoff sediment concentration increases, rill erosion becomes severe, runoff stop time advances, besides the moisture decreases with increasing slope after the rainfall. When initial soil moisture is 15% and rainfall intensity is lmm/min, from slope 5° to 10°～15°, total runoff amount increases 12.43%～38.73%, average soil infiltration rate decreases 11.73%～20.22%, and significantly enhance the total amount of soil erosion from 5.8 to 42.5 times. overall, the slope of the greater degree of increased soil erosion.(2)Under conditions of some rainfall intensity, slop and straw coverage, as the soil bulk density increasing, runoff start time advances, soil infiltration capacity becomes poorer, runoff amount increases, runoff gradually increases, the erosion intensity of surface soil increases, soil erosion including rill erosion becomes severer. When initial soil moisture is 15% and rainfall intensity is lmm/min, soil bulk density increasing froml.2g/cm3 to 1.4g/cm3～1.6g/cm3, total runoff amount increases 41.92%-169.49%, average soil infiltration rate decreases 8.28%～27.19%, and significantly enhance the total amount of soil erosion from 5.8 to 42.5 times, overall, the soil bulk density of the greater of increased soil erosion.(3)Under conditions of some rainfall intensity, slop and soil bulk density, straw coverage can extend the time to produce runoff 1-10min, to postpone the time to stop runoff and increase the infiltration rate, significantly reduce surface runoff. When initial soil moisture is 15% and rainfall intensity is 1mm/min, the coverage amount is 0.2kg/m2～0.4kg/m2, total runoff amount decreases 18.81%～40.27%, average soil infiltration rate increases 5.69%～12.17%, and significantly decreases the total amount of soil erosion 53.69%～79.92%,decrease rill erosion. overall, the straw coverage can reduce soil erosion obviously.(4)By Excel, SPSS Statistics 22 data analysis software, obtained the regression curve equation of runoff, sediment yield, soil infiltration rate over time changing in artificial rainfall runoff district, Introduction of soil erosion influencing factors, analyze significantly influence extent of each factor on each index in soil erosion. Then established Prediction Model between runoff start time, runoff amount, runoff stop time, sediment yield, average infiltration rate, rill erosion and soil moisture and slop, soil bulk density, straw coverage When initial soil moisture is 15% and rainfall intensity is lmm/min.