细沟股流剥蚀率与载沙量以及沟长的耦合关系

Coupling Relationship Between Detachment Rate with Sediment Load and Rill Length

土壤剥蚀是指由侵蚀动力引起的土壤颗粒从土壤母质移动的过程。细沟剥蚀土粒随着细沟股流中含沙量的增加而减少 ,已有的一些侵蚀模型 (如 WEPP)均提到了这一点。用黄土高原一种典型的粉壤土 ,在 5种坡度、3种流量下进行了细沟侵蚀模拟试验。对试验结果进行了回归 ,分析了黄土高原斜坡及陡坡地、细沟股流剥蚀率随含沙量以及沟长变化的函数关系。这对细沟侵蚀动力过程的研究深入 。

The term soil detachment implies a process description: the removal of one or many soil particles as a function of some driving force (erosivity) such as shear stresses of flowing water. Soil detachment from rill bed decreases with increase of sediment concentration in the flow, as many erosion models such as WEPP suggests. Using a typical silt clay soil from the Loess Plateau, a method is developed to compute the detachment rate of sediment loading water flow, under the assumption that the flow and soil are behaving the same way along rills. Then detachment rates are presented as functions of sediment load and rill lengths. A series of 405 flume experiments were conducted on 5 different slopes, 3 flow rates and 8～9 slope length, with 3 replicates for each.