不同土壤类型坡面的产流产沙特征及其主要影响因素OA

[Objective]The study aims to investigate differences in sediment and runoff yield characteristics on hillslopes with various soil types and their primary influencing factors,providing insights into erosion mechanisms across various soils.[Methods]Simulated rainfall experiments were conducted on red loam,black soil,purple soil,and sandy loess soil under different rainfall intensities(60 and 120 mm/h)and slope gradients(10°,15°,and 20°).Runoff and sediment yield characteristics were analyzed,and their main influencing factors were identified.[Results](1)The runoff rates of fine-grained soils(red loam,black soil,purple soil)were 4.3%～37.2%higher than those of coarse-grained soil(sandy loess soil),whereas sediment yield rates of coarse-texuted soil were 0.3～10.8 times higher than those of fine-texuted soils.(2)Among the fine-texuted soils,the sediment yield of red loam and purple soil increased steadily,while that of black soil increased rapidly at the initial stage before stabilizing.In contrast,sediment yield from the coarse-texuted soil under high rainfall intensity and steep slopes(120 mm/h rainfall intensity on 15°and 20° slopes)exhibited a"sharp increase followed by a sharp decrease"pattern.(3)For hillslopes with different soil types,soil erodibility,represented by the K value,contributed 34.9%to sediment yield rate.Rainfall intensity contributed 57.6%～85.6%to sediment yield in fine-texuted soils.For sandy loess soil,rainfall intensity and slope gradient were important factors influencing sediment yield,contributing 44.9%and 36.6%,respectively,significantly higher than their effect on fine-grained soils.[Conclusion]Rainfall intensity is the primary driver of sediment yield in fine-grained soils,whereas both slope gradient and rainfall intensity jointly determine the sediment yield characteristics on coarse-grained soil slopes.