川中丘陵区坡耕地侵蚀空间分布的WEPP模型和^(137)Cs法研究  

Combing Wepp Model with ^(137)Cs to Study Spatial Pattern of Soil Redistribution on Purple Slope-Land in Sichuan Hilly Basin

作　　者：郑进军[1] 张信宝[1] 贺秀斌[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

出　　处：《水土保持学报》2007年第2期19-23,共5页Journal of Soil and Water Conservation

基　　金：国家自然科学基金(40671120);科技部973项目(2003CB415801);国际原子能机构(12300/RO)资助

摘　　要：当前核素示踪技术和侵蚀产沙模型联合应用于侵蚀空间分异规律研究甚少且主要集中在流域尺度上。本研究利用WEPP模型和137Cs核素示踪技术估算了川中丘陵区简阳县贾家村附近两块坡耕地的侵蚀速率,进而对两种方法估算的侵蚀速率在坡面上的空间分布规律进行了分析。研究表明用137Cs核素示踪法测算的两块坡耕地的侵蚀速率随坡长增加而呈波动变化特征,用WEPP模型估算的坡耕地和坡耕地的土壤侵蚀速率随坡长增加而增大。坡耕地I顶部极高的137Cs计算的侵蚀速率和极低的WEPP模型计算的侵蚀速率表明人工刨地耕作逐渐把该坡耕地顶部的耕作土迁移至下部并将坡顶变成该坡耕地内最贫瘠的部分。用WEPP模型模拟的侵蚀速率与用137Cs计算的侵蚀速率在量上和空间分布上都有较大的不同,这说明在川中丘陵区用WEPP模型来估算传统耕作方式下坡耕地的侵蚀速率存在一定的局限性。Many studies contribute to the validation of erosion and sediment yield models using environment radionuclide, plot survey and runoff plots monitoring data in catchment scale. However joint use of erosion models and radionuelide tracing measurements to study the spatial pattern of soil redistribution in hillslope scale are scarcely any. The WEPP model combined with ^137Cs measurement are used to study the spatial pattern of soil redistribution in two purple cultivated slopes under hoeing tillage, water erosion and the traditional farming method ＂Tiaoshamiantu＂ in the Siehuan Hilly Basin. The soil redistribution by a3VCs presents a rolling trend and those by the WEPP model increase with slope length in the two hillslopes. Soil redistribution rates for hillslope Ⅰ and hillslope Ⅱ by ^137Cs are greater than these values by the WEPP model. Extremely high tillage erosion rates by ^137Cs and very low water erosion rates by the WEPP model in the top sites of hillslope Ⅰ and hillslope Ⅱ suggests that the ridge top of hillslope have been gradually razed by hoeing tillage.

关 键 词：紫色土 土壤侵蚀 WEPP模型 ^137CS 川中丘陵区 

分 类 号：S157.1[农业科学—土壤学] S124[农业科学—农业基础科学]