黄土区土质道路人工降雨及放水试验条件下产流产沙特征

为了研究土质路面草本植被降低水土流失的作用，采用室内人工降雨及放水试验的方法比较了裸露路和植物路的产流产沙过程及径流水动力学特征，结果表明：相对于裸露路，不同覆盖度植物路总径流量降低幅度为3.94%～ 25.10%，总泥沙量降低幅度为9.65%～45.69%；在大致相同放水量条件下，植物路的土壤侵蚀速率、径流流速和过水断面单位能量均低于裸露路；植物路的Darcy-weisbach阻力系数和曼宁糙率系数分别是裸露路的2.62～9.00倍和1.74～ 3.53倍；植物路通过降低径流流速、减小过水断面单位能量和增大路面粗糙度及径流阻力起到减轻道路侵蚀的作用。该文为广大土质山坡道路侵蚀防治和植物路铺设提供理论支持。

Runoff and sediment yield characteristics of earth road under artificial rainfall and simulated overland flow tests conditions in Loess Plateau

An artificial rainfall and simulated overland flow test was conducted to study runoff and sediment yield process and hydraulic characteristics of uncovered earth road and grass-covered earth road in order to decrease soil and water loss on grass-covered earth road surface. Total runoff and sediment yield decreased 3.94%-25.10% and 9.65%-45.69% respectively of grass-covered earth road compared with uncovered earth road. At same flow rate, grass-covered earth road had lower soil erosion rate, runoff velocity and unit energy of water-carry section. Darcy-weisbach resistance coefficient and Manning roughness coefficient of grass-covered earth road was 2.62-9.00 times higher and 1.74-3.53 times higher respectively than that of uncovered earth road. Because of its lower runoff velocity and unit energy of water-carrying section, higher road surface roughness coefficient and runoff resistance coefficient, grass-covered earth road had a lower sediment yield and could decreased sediment transport. The study provides theoretical support for decreasing uncovered earth road erosion and paving grass-covered earth road.