半湿润区农田土壤风蚀的风洞模拟研究  

Research on Farmland Soil Wind Erosion Characteristics in Semi-humid Region by Wind-tunnel Simulation

作　　者：王仁德[1,2,3] 邹学勇[2,3] 赵婧妍[2,3] 

机构地区：[1]河北省科学院地理科学研究所,河北石家庄050011 [2]北京师范大学地表过程与资源生态国家重点实验室,北京100875 [3]北京师范大学中国沙漠研究中心,北京100875

出　　处：《中国沙漠》2012年第3期640-646,共7页Journal of Desert Research

基　　金：国家"十一五"科技支撑项目(2006BAD26B03);国家自然科学基金项目(40971011);国家自然科学基金青年项目(41101251)共同资助

摘　　要：采用风洞模拟手段对地处半湿润区的北京市农田土壤风蚀特征进行研究。结果表明,几类农田的风蚀特征存在较大差距,秋季翻耕不耙平地风蚀强度最大,玉米留茬地次之,翻耕耙平地最弱,垄向和风速对农田风蚀特征影响显著。各类农田风蚀强度均随风速增大呈指数规律增加,初始风蚀强度与风蚀强度增幅之间具有反对应关系,低风速时风蚀强度越大的地类,其风蚀强度随风速增加的越慢。输沙量随高度增加而减少,近地表减少较快,向上随着高度的增加减幅逐渐变缓。低风速时,风蚀物的垂向分布服从幂函数递减规律。随着风速增加,风蚀物粒径不断变粗,风蚀物的垂向分布在近地面服从指数函数递减规律,向上服从幂函数递减规律,并且风速越大,指数函数规律递减层的高度越大。The soil wind erosion features of farmlands located in Beijing region, a semi-humid region, were studied by means of wind-tunnel simulation experiment. Results showed that the wind erosion characteristics of different types of farmland land surfaces were significantly different. The wind erosion intensity of un- raked ploughed farmland was the largest in all, that of stubble farmland was in the second, and that of raked ploughed farmland was the weakest. The influence of field ridge direction and wind direction on wind ero- sion was obvious. With wind speed increasing, wind erosion intensity of all types of farmlands presented ex- ponential increase regularity. There was a negative correlation between the initial wind erosion strength and the wind erosion strength increase rate. The farmlands that had stronger wind erosion strength in low wind speed had less wind erosion increase rate with wind speed increasing. The sand transportation reduced with height, and its reduction rate was fast in near-surface layer and became slow with height increasing. The vertical distribution of wind erosion sediments followed a power decreasing law with height in smaller wind speed. The size of wind erosion sediments became larger with wind speed increasing, and their vertical vari- ation followed an exponential decreasing law in near-surface layer, and then followed a power decreasing law with height increasing. The faster the wind speed was, the higher the exponential decreasing rate was.

关 键 词：土壤风蚀 风洞模拟 半湿润区 

分 类 号：X169[环境科学与工程—环境科学]