摘要
在中国科学院水利部水土保持研究所,采用2个不同坡长小区室内模拟降雨试验方法,对黄土坡面下坡位侵蚀过程进行研究。结果表明:1)坡面下坡位侵蚀模数随降雨过程、降雨强度及坡度的变化均具有大小交错,上下波动的特征,侵蚀模数随降雨过程的变化总体呈先上升后趋于稳定的态势,随降雨强度的增大而增加,随坡度的增大而先增大后减小,再增大再减小;2)坡面上、下坡位侵蚀模数随降雨过程、坡度及降雨强度的变化均具有明显差异,下坡位明显不如上坡位;3)坡面上坡位汇流和下坡位产流与坡面上坡位输沙对坡面下坡位侵蚀模数的影响可用二元线性方程很好地描述,前者的贡献率为47.8%,后者为20.4%;只通过观测分析小区平均侵蚀特征得出的坡面侵蚀过程,掩盖了坡面下坡位的真实侵蚀过程,采取水土保持措施减少坡面上坡位汇流及增加降雨就地入渗,可以有效地治理坡面下坡位的水土流失。
In the process of water erosion, runoff and sediment yield vary with the different segments of a hillslope. Clarifying the mechanism of erosion processes can provide a scientific basis for soil and water conservation measures. In this study, erosion processes on downslope were investigated using two flumes with different lengths under simulated rainfall. Results showed that 1 ） downslope erosion intensity varied with rainfall process, rainfall intensity, and slope gradient, characterized by up-down fluctuations. 2） Erosion intensity varying with rainfall process, slope, and rainfall intensity between different segments on the same slope was obviously different. 3） Runoff from both of the upslope and the downslope and sediment on the upslope had impacts on erosion intensity on the downslope and the impacts could be well described with a linear equation, with the former contribution being 47.8 % and the latter, 20.4 %. It can be concluded that only observation and analysis of average erosion characteristics cover up the detailed erosion processes. Taking soil and water conservation measures to reduce flow concentration from upslope and increase rainfall infiltration can effectively control soil erosion on downslope.
出处
《中国水土保持科学》
CSCD
2009年第2期12-17,28,共7页
Science of Soil and Water Conservation
基金
国家973计划课题"不同类型区土壤侵蚀过程与机理"(2007CB407201)
中科院知识创新工程重要方向项目"黄河多沙粗沙来源区小流域水土流失过程与机理研究"(KZCX2-YW-442)
黄土高原土壤侵蚀与旱地农业国家重点实验室自主研究项目"黄土高原近万年来土壤侵蚀发生演变与趋势预测"
西北农林科技大学创新团队建设计划"黄土高原土壤侵蚀及其治理环境效应评价"(01140202)
关键词
黄土
坡面
下坡位
土壤侵蚀过程
汇流
输沙
loess
hillslope
downslope segment of hillslope
soil erosion process
flow concentration
sediment load
