威连滩冲沟砂黄土的风蚀与降雨侵蚀模拟实验  

Simulated Experiment of Erosion by Wind and Rainfall on Sandy Loess in Weiliantan Gully

作　　者：宋阳[1] 严平[1] 刘连友[1] 杨恒华 朱孟郡[1] 杜建会[1] 马玉凤[1] 

机构地区：[1]北京师范大学资源学院 [2]青海省治沙试验站,青海共和813005

出　　处：《中国沙漠》2007年第5期814-819,共6页Journal of Desert Research

基　　金：新世纪优秀人才支持计划(NCET-05-148);国家科技攻关计划(2005BA517A06);国家自然科学基金(40541005)共同资助

摘　　要：通过风洞与模拟降雨实验,研究了风力与降雨对青海省贵南县威连滩冲沟砂黄土的复合侵蚀作用。实验得出:①风蚀后的降雨使砂黄土表面在风干过程中形成了一层较为坚硬的结壳,增大了土壤的抗蚀性,降低了第二次风洞实验后期的风蚀率;②土壤水分与人为扰动是影响土壤风蚀的两个重要因素。当土壤水分较小时,风蚀率受人为扰动影响巨大;当土壤水分较大时,人为扰动对土壤风蚀的影响较小;③在持续降雨的实验条件下,砂黄土的产流、产沙量随着雨强的变化而改变。这种变化与表土的侵蚀率、可蚀性物质的多少、土壤水分以及土壤的入渗率等都有很大的关系。Weiliantan gully is located at Guinan County, Qinghai Province, which is surfured from serious soil erosion by both wind and water. In this study, sandy loess samples of Weiliantan gully are collected, and through wind tunnel and simulated rainfall experiment, the processes of complex erosion by wind and rainfall on sandy loess of Weiliantan gully is studied. The results of these experiments can be summarized as three parts.①Rainfall after first wind tunnel experiment formed hard soil crust, so the resistance of soil to erosion was strengthened, then the wind erosion rate was decreased in the next wind tunnel experiment. ② Soil moisture and human disturbance are two important influencing factors of wind erosion. These two factors play different roles in wind erosion. When soil moisture is low, human disturbance can have great influence on wind erosion. When soil moisture is high, wind erosion can hardly be affected by human disturbance. ③ In the continuous simulated rainfall experiment, the runoff yield and sand discharge of sand loess changed with the rainfall intensity. This change is associated with the erosion rate of surface soil, the content of erodible particles, soil moisture and infiltration rate, etc.

关 键 词：冲沟 风水复合侵蚀 风洞实验 模拟降雨试验 威连滩 

分 类 号：S157.1[农业科学—土壤学]