THE MECHANISM OF SEDIMENT YIELD AND HARNESS COUNTERMEASURE FOR LITTLE VALLEYS IN THE MIDDLE REACHES OF THE YELLOW RIVER
Wang Yaping (Department of Geography,Nanjing Normal University,210024)
Based on the difference of the valley surface of the middle reaches of the Yellow River,the paper fall this study area roughly into three categories:loess area,rock area,wind-sand area.By the analysis of the sediment yield factor of the three areas,three conclusions can be drawn as follow: 1.In the three area,harness degree,rainfall,rain strength,runoff depth all affect the sediment yield in varying degree,and runoff depth is closestly related to sediment yield modulus.There is a negative relation between harness degree and sediment yield modulus. 2.According to the dynamics of sediment yield,runoff depth and rainfall are the major factors affecting sediment yield in loess area and rock area.But in wind-sand area,wind is an important factor that cannot be ignored.The sediment yield occurs basically during flood season in loess area and rock area. 3.It is natural factor and social factor that affect the sediment yield.Thus,a principle synthetical countermeasure should be insisted on.
【CateGory Index】： S157.1