【摘要】 采用人工模拟降雨试验的方法对黄土坡面土壤侵蚀动态变化过程进行了研究。(1)不同雨强条件下,土壤侵蚀强度随降雨过程的动态变化趋势基本一致,整体皆随降雨历时的增长而递增,并皆可用对数线性组合方程很好地描述。开始降雨后的15min和35min是侵蚀强度随降雨过程变化的转折点;(2)不同坡度条件下,土壤侵蚀强度皆随雨强的增大而迅速增大,变化趋势基本一致,可用线性方程很好地描述;(3)不同雨强条件下,土壤侵蚀强度随坡度的增加表现为先增大后减小的趋势,可用对数线性组合方程很好地描述,25°左右是侵蚀强度发生变化的临界坡度;(4)不同雨强条件下,土壤侵蚀强度随坡长的增加整体表现为先增大后减小的趋势,可用对数线性组合方程很好地描述,坡长80cm左右是侵蚀强度发生变化的转折点;(5)土壤侵蚀强度随雨强、坡度、坡长的动态变化可用三元线性方程描述,雨强对土壤侵蚀的影响远超过坡度与坡长,且坡度与侵蚀强度的关系较坡长为密切。更多还原

【Abstract】 Based on simulated rainfall experiment,the processes of soil erosion dynamic variation on the loess hillslope were studied and the following results were obtained:(1) Soil erosion rate was increased with rainfall process under different rainfall intensities and it could be described with a logarithmic and linear combined equation.15 min and 35 min after rainfall beginning were the turning points of soil erosion rate with rainfall process.(2) Soil erosion rate was increased rapidly with the increase of rainfall intensity at different slope gradients and it could be described with linear equation.(3) Soil erosion rate varied with the increase of slope gradient at different rainfall intensities,having a trend of increase to decrease,and it could be described well with a logarithmic and linear combined equation.The critical slope gradient was about 25°.(4) Soil erosion rate varied with the increase of slope length at different rainfall intensities,having a trend of increase to decrease,and it could be described well with a logarithmic and linear combined equation.80 cm of slope length is the turning point of soil erosion rate.(5) Effects of rainfall intensity,slope gradient,and slope length on soil erosion could be described with a ternary linear equation.The influence of rainfall intensity on soil erosion is more significant than slope gradient and slope length and slope gradient is more important than slope length.更多还原