紫色土坡面降雨侵蚀试验研究  

A Study on the Process Simulation of Soil Erosion by Rainfall on the Purple Soil Slopes

作　　者：王玉宽[1] 王勇强[1] 傅斌[1,2] 王先拓[1] 王道杰[1] 

机构地区：[1]中国科学院水利部成都山地灾害与环境研究所 [2]中国科学院研究生院,北京100049

出　　处：《山地学报》2006年第5期597-600,共4页Mountain Research

基　　金：国家973计划项目(2003CB415202);中科院创新项目(KZCX3-SW-330)

摘　　要：坡面水蚀的主要侵蚀动力来自降雨及其产生的地表径流,将坡面水蚀过程分为降雨侵蚀和径流侵蚀,可以从侵蚀动力、侵蚀特征差异与侵蚀规律等方面研究坡面水蚀过程与机理。应用人工模拟降雨及微小区测定技术,以大田紫色土为研究对象,模拟和测定不同雨强与不同坡度条件下降雨侵蚀过程和侵蚀量,揭示以降雨为主要动力的土壤降雨侵蚀特征和规律。研究结果表明：(1)小雨强(＜67．26 mm/h)下,紫色土坡面降雨侵蚀率具有稳定性,随着降雨历时的增加变化微小；大雨强(106．57 mm/h)下,降雨侵蚀率随降雨历时增加呈上下波动；(2)紫色土降雨侵蚀率与降雨强度呈线性相关,随降雨强度增加而直线增加；(3)降雨侵蚀率与坡度符合二次抛物线关系,随坡度的增加出现临界坡度,且临界坡度随雨强的变化而改变。在中小雨强(18．06～67．26 mm/h)条件下,临界坡度SK的变化范围在17°～19°。在大雨强条件下,临界坡度有逐渐增大的趋势；(4)当坡度与雨强共同影响产沙效应时,坡度对降雨侵蚀的影响较小,雨强能掩盖坡度对产沙的贡献。As the dominant soil classification in Sichuan Basin, purple soil covers a large area and is crucial for local forestry and agriculture. But due to its slope distribution and fragile property, it experiences serious erosion during rainfalls. This study was conducted by using manual simulation rainfall apparatus and applying a micro-box design method to survey the erosion process on different purple soil slopes. The results showed that （ 1 ） Rainfall intensity and time can slightly change the slope erosion rate and a general trend can be described as ＂even-up-evendown-even＂ pattern while rainfall intensity and rainfall time increase ; （2） At different slope angles, non-liner correlations can be analyzed between soil erosivity and erosion rate. Rainfall increase can result in increase in erosion and spilling effect; （3） In different rainfall intensities, soil erosion rate can be varied with slope angle ascends. And an SK value exists between 17% - 19% but ascends with rainfall intensity increases; （4）Different slope angles can slightly affect the sheet erosion while co-functioning with rainfall intensity.

关 键 词：紫色土 坡面降雨侵蚀 人工模拟降雨 

分 类 号：S155.25[农业科学—土壤学] S157[农业科学—农业基础科学]