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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。
Wind tunnel simulation was used to study the characteristics of wind erosion in farmland in Beijing, which is located in a semi-humid area. The results showed that there was a big gap between the wind erosion characteristics of several types of farmland. In autumn, the wind erosion intensity was the highest in non-raking area, followed by stubble in corn, the weakest tillage rake level, and the effect of ridge and wind speed on wind erosion in farmland. The wind erosion intensity of all kinds of farmland increases exponentially with the increase of wind speed. There is a negative relationship between the initial wind erosion intensity and the increase of wind erosion intensity. The wind erosion intensity increases with the increase of wind speed when the wind speed is low SLOW. The amount of sediment decreased with the increase of altitude, the decrease of near surface decreased rapidly, and the decrease gradually increased with the increase of altitude. At low wind speeds, the vertical distribution of wind erode obeys the law of decreasing power function. With the increase of wind speed, the size of the wind eroded material continuously becomes thicker. The vertical distribution of wind eroded objects obeys the decreasing law of exponential function in the ground surface and obeys the decreasing law of power function, and the greater the wind speed, the greater the height of the descending layer of exponential function.