红壤坡地降雨产流产沙动态过程模拟试验研究

研究以浙江省兰溪水土保持综合试验站为研究基地,通过设定特定植被覆盖度（15%）不同坡度（8°、15°、20°）的径流试验小区,小区面积为2m2,采用野外人工模拟降雨试验方法,对降雨强度（0.8～2.9mm·min-1）范围内,红壤坡地产流和产沙随雨强和坡度的变化特性进行了模拟试验。通过32场模拟降雨试验数据的分析,得出结论如下：①产沙量与雨强呈指数函数关系,产流量与雨强呈幂函数关系,径流量与产沙量的相关性大于雨强与径流、雨强与产沙;②随坡度的增大,产流时刻提前,泥沙起动和产沙突增的雨强临界减小;③随坡度增大,累积产沙量的递增速率比累积径流量的递增速率要快;④场降雨侵蚀模数与雨强的相关性随着坡度的增大而增强。

Research on the processes of rainfall,surface runoff and sediment on sloping field with red loam by simulated rainfall experiment

In this research,the process experiments of runoff and sediment yield under different rainfall intensities were conducted with different red loam slopes by artificial simulated rainfall ways,at soil and water conservation station in the Lanxi city of Zhejiang province.The testing runoff plot were designed with the slope of 8°,15°,20°,the vegetation cover degree of 15%,rainfall intensity of 0.8～2.9 mm·min-1 ,and the area of 2 m 2 .The change characteristics of runoff and sediment yield were mainly analyzed on the basis of simulated rainfall of 32 sets.Some conclusions were obtained and listed as follows：①The relationship betweensediment and rainfall intensity is exponential function,runoff and rainfall intensity is power function.The relativity between runoff and sediment is better than rainfall intensity and runoff,rainfall intensity and sediment.②As slope increases,the time for runoff occurrence has been moved up,and the critical rainfall intensity for sediment start moving and abruptly increasing are reduced.③As slope increases,the increasing rate of accumulative sediment is faster than that of accumulative runoff.④As slope increases,the relativity between erosion modulus and rainfall intensity heightens.