关键词: 土壤风蚀, 风洞模拟, 半湿润区

Abstract: 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 erosion was obvious. With wind speed increasing, wind erosion intensity of all types of farmlands presented exponential 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 variation 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.

Key words: soil wind erosion, wind-tunnel simulation, semi-humid region