沙漠风积沙溯源冲刷速度的影响因素初探

A Preliminary Study on the Factors Affecting the Headward Erosion Rate of Desert Aeolian Sand

通过试验对沙漠风积沙的冲刷破坏形态以及影响沙漠风积沙溯源冲刷速度的主要因素进行初步分析。结果表明:在具有跌坎的地形上,沙漠风积沙在集中水流冲刷下,表面的冲刷剥蚀速度远小于跌坎处的溯源冲刷速度;沙漠风积沙的溯源冲刷速度与通过沙漠风积沙表面水流的单宽流量、跌坎处初始落差以及沙漠风积沙的含水率等因素有关;在初始落差一定的情况下,溯源冲刷速度随单宽流量的增大而加快;在相同单宽流量作用下,溯源冲刷速度随初始落差的增大而增大。

Through experiment this paper analyzed the desert aeolian sand erosion failure pattern under the action of water and the main factors influencing the failure back desert aeolian sand speed,the results show that,in terrain with a slump,desert aeolian sand under concentrated water flow,scour on the surface of the desert aeolian sand erosion rate is far less than drop headward erosion speed; the headward erosion speed of desert soil depends on the unit discharge of the overtopping flow through the surface water of the desert soil,the initial step height and the moisture content and the density of the desert soil. When the initial step height is the same,the greater the flow rate,the faster the damage rate; when the unit discharge of the overtopping flow is the same,the higher the initial step height,the faster the headward erosion rate of desert aeolian sand.