水土保持学报2017，Vol.31Issue(4)：6-10,31,6.DOI:10.13870/j.cnki.stbcxb.2017.04.002
模拟径流条件下覆沙黄土坡面产流产沙过程
Runoff and Sediment Yield Process on the Sand-covered Loess Slopes Under Simulated Runoff Conditions
摘要
Abstract
Runoff and sediment yield process on sand-covered loess slopes under simulated runoff conditions were studied through simulating wind-water complex erosion based on the controlled scouring experiments.This study set up three water flow rates (5,10,and 15 L/min) and five sand-covered thicknesses (0,5,15,25 and 35 mm).The results showed that the runoff yield time on the sand-covered slope was extended,and it extended with the increasing of sand-covered thickness.Under different water flow rate,the runoff yield time on sand-covered slopes (5,15,25,35 mm) were 1.29～1.46 times,1.66～2.5 times,2.5～3.76 times and 3.76～4.72 times,respectively,than those on the loss slope.Compared to the loess slope,sediment yield contribution rate was greater than runoff contribution rate on the sand-covered slope.Under the same water flow rate,the total amount of runoff on sand-covered slope was 1.05～1.8 times of that on the loess slope,and the total amount of sediment yield was 1.6～7.5 times.Under different water flow rates,the increase-rate of runoff rate on the sand-covered slope was significantly higher than that on the loess slope within 0～5 min,and in the later 25 min of runoff,increase rates of runoff rate on both two kinds of slopes were basically coincident.In the whole runoff,the fluctuation of runoff rate on sand-covered slope was significantly higher than that on loess slope.With the increasing of water flow rate,the initial sediment yield strength on sand-covered slope significantly increased.However,in the same water flow rate,the initial sediment yield strength did not increased significantly with the increasing of sand-covered thickness.Under different water flow rates and different sand-covered thicknesses,the sediment yield strength firstly increased dramatically,then decreased,and then gradually reached a steady state,and the fluctuation of sediment yield strength on the sand-covered slope was significantly higher than that on the loess slope.The results indicated that the sand-covered slope destroyed the stability of the water flow,and aggravated soil erosion at a certain extent.关键词
风水复合侵蚀/冲刷试验/覆沙黄土坡面/侵蚀产沙Key words
wind-water complex erosion/scouring experiment/sand-covered loess slopes/erosion and sediment yield分类
农业科技引用本文复制引用
张洋,李占斌,牛雯,段金晓..模拟径流条件下覆沙黄土坡面产流产沙过程[J].水土保持学报,2017,31(4):6-10,31,6.基金项目
国家自然科学基金重点项目(41330858) （41330858）
国家自然科学基金项目((41471226)) （(41471226）
