黄土坡面下坡位片蚀过程试验研究  

Experimental Study on Sheet Erosion Process on Down Slope Segment of Loess Hillslopes

作　　者：刘俊娥[1] 王占礼[2,3] 高素娟[1] 张宽地[4] 陈浩[1] 王莎[1] 

机构地区：[1]西北农林科技大学资源环境学院,陕西杨凌712100 [2]西北农林科技大学水土保持研究所,陕西杨凌712100 [3]中国科学院水利部水土保持研究所黄土高原土壤侵蚀与旱地农业国家重点实验室,陕西杨凌712100 [4]西北农林科技大学水利与建筑工程学院,陕西杨凌712100

出　　处：《水土保持通报》2011年第5期23-27,共5页Bulletin of Soil and Water Conservation

基　　金：国家自然科学基金项目"黄土坡面细沟侵蚀动力学过程组合小区试验研究"(40971172);国家973计划课题"不同类型区土壤侵蚀过程与机理"(2007CB407201);中国科学院知识创新工程重要方向项目"多沙粗沙区土壤水蚀机理研究"(KZCX2-YW-442-04);黄土高原土壤侵蚀与旱地农业国家重点实验室专项经费资助项目"坡面流及其输沙侵蚀动力学特征"(10502-Z12-7)

摘　　要：坡面片蚀强度具有沿程空间变化性,阐明坡面不同坡位的片蚀过程对于完善坡面土壤侵蚀理论具有重要意义。采用组合小区模拟降雨试验方法对黄土坡面下坡位片蚀过程进行了研究,结果表明:(1)坡面下坡位片蚀特征与坡面上坡位及全坡面片蚀特征存在差异,下坡位片蚀规律性较差;(2)坡面下坡位片蚀随降雨过程、雨强和坡度的变化均呈现波动性,总体上随降雨过程先增大后稳定,随雨强及坡度的增大而增大;(3)坡面下坡位片蚀随雨强和坡度的变化可用二元线性方程描述,雨强的影响远大于坡度;(4)坡面上坡位汇流和下坡位产流及上坡位输沙对下坡位片蚀的影响可用二元线性方程描述,其中前者贡献率为56.9%,后者贡献率为25.4%,水的作用显著大于沙的作用。采取增加坡面入渗、减少径流的水保措施可有效防治坡面下坡位片蚀。As sheet erosion has spatial variations along slope,it is important for the improvement of soil erosion theory to explain soil erosion process on different segments of a hillslope.Sheet erosion characteristics on downslope were analyzed based on experiments of simulated rainfall with multiple plots.The results show that the sheet erosion characteristics on the down slopes differed from those on the whole slopes and upslopes.The sheet erosion on downslopes displayed extremely strong variability.The sheet erosion rates fluctuated with rainfall course,rainfall intensity,and slope gradient.Generally,it increased with the increased time at beginning and then stabilized.The rate increased with slope gradient and rainfall intensity.The variation of sheet erosion modulus with rainfall intensity and slope gradient can be described by a duality linear equation and rainfall intensity affected sheet erosion modulus much greater than slope gradient.The impact of runoff from both upslope and downslope and sediment from upslope on downslope sheet erosion were described by a duality linear equation,with contributions of 56.9% and 25.4%,respectively.Runoff had a greater effect than sediment.It can effectively control sheet erosion on downslope to take measures such as increasing the infiltration and reducing runoff.

关 键 词：黄土坡面 下坡位 片蚀 

分 类 号：S157.1[农业科学—土壤学]