粉尘释放是风蚀造成危害的一个重要过程。以农牧交错带沙区和非沙区农田土壤为研究对象，利用室内风洞模拟实验，实时监测了风蚀过程中释放的PM10，分析了PM10的动态变化特征，以深入认识土壤风蚀粉尘释放机理。结果表明：非沙区农田土壤风蚀强度远低于沙区农田，与风速呈指数函数关系；非沙区农田的土壤粉尘释放在不同风速下均以气流直接抬升模式为主，平均PM10通量与风速呈线性函数关系，最大PM10通量与风速呈幂函数关系；沙区农田的土壤粉尘释放在风速增大到一定程度后呈气流直接抬升和砂粒跃移冲击复合模式，最大PM10通量增加不明显，但平均PM10通量明显高于非沙区农田；对于沙区和非沙区农田而言，平均PM10通量与风蚀速率呈对数函数关系。
Dust emission is a process triggered by wind erosion to deteriorate atmospheric environmental quality. By taking cultivated soils from sandy area and no-sandy area in the ecotone between agriculture and animal husbandry as research object, we monitored concentration of PM10 in the wind-flow emitted from soil surface in wind tunnel simulation experiment. In order to understand the mechanic of PM10 emission during the wind erosion, we analyzed the characteristic and regularity of temporal variation of PM10. The following conclusions have been obtained: wind erosion rate of cultivated soils from no-sandy area is much lower than sandy area while there is a exponential function relationships between wind erosion rate and wind speed; Being mainly aroused by the direct suspension, the average PM10 flux of cultivated soils from no-sandy area linearly increase with increasing wind speed, and maximum PM10 flux of those soils increase in a power function trend with wind speed. Resulted from uplift by combination of direct suspension and saltation, the average PM10 flux of soils from sandy area is much higher than those from no-sandy area while maximum PM10 flux increase is low. For all soil samples, there is a logarithm function relationship between average PM10 flux and wind erosion rate.
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