The Analysis of Relationships between Rainfall and Warp Dam Block Sediment in Jinghe Watershed

Abstract

Analyzed the relationships between rainfall and warp dam block sediment in Jinghe watershed in different years by regression analysis method base on the nearest material, the date shows: (1) The respond relation is changes between the warp dam retains sand and the rain in Jinghe river basin,80's is the biggest. The critical value is 1×107 t/a;the 1d and rain season and year rain critical value is bigger than 40mm,350mm,450mm. (2) The relationships between rainfall and warp dam block sediment in Jinghe watershed were different, it had two areas include high and low block sediment base the rainfall; the high value is 3.55 times than low value. The block sediment amount of warp dam will be calculated by the corresponding relation base the actual amount of rainfall flood in watershed. (3) The warp dam retains sand amount is about 0.016t/m3 in 1 m3 flood at 80's in Jinghe river basin, the warp dam retains sand is about 0.0045t/m3 in 1 m3 flood at other years in Jinghe river basin, was growing to 0.021t/m3 near period. (4) They have the line relation between warp dams reduce sediment and soil erosion in different spatial scale river basin in middle of yellow river. The rate of reduce sediment to retain sand increase with the area decrease.