沙尘暴对人类生存的自然环境和社会经济健康发展造成严重影响。近70年来，中国西北沙尘暴天气总体减少，但自2021年开始，沙尘暴发生频率和范围明显增加。沙尘暴的发生和发展是气流与地表可蚀性物质的互馈过程，因此，沙尘在源区的起动过程决定了沙尘暴发生发展的整个过程。尽管目前对沙尘的运动过程进行了大量的数值模拟、遥感解译等研究，但野外实测资料缺乏，难以阐明沙尘暴期间的风沙活动强度及沙尘运动的物理机制。利用2021年1月在额济纳旗附近戈壁的野外实测输沙量和PM₁₀等沙尘资料，解释沙尘物质在源区的运动特征，阐明戈壁风沙运动机理，为沙尘源区风沙灾害防治提供理论依据。结果表明：（1）沙尘源区沙尘暴期间风速可大于19.6 m·s^-1，远高于同期当地国家气象站数据（10.5 m·s^-1）。（2）PM₁₀浓度100 mg·m^-3，远高于同期当地国家环境监测站数据。（3）戈壁输沙量可达10 kg·m^-1·h^-1，最大输沙量位于地表以上0.07 m高度，这一过程导致戈壁沙尘能够远距离运动。（4）1 m高度平均粒径为0.07 mm，意味着戈壁风沙流以极细沙、粉沙和黏粒为主，PM₁₀含量可达8%，粗沙含量可达9%，运动粗沙碰撞破坏戈壁地表，导致更多的沙尘物质进入空气。（5）车辆碾压戈壁地表导致输沙率是原始地表的2倍，PM₁₀浓度增加2.90倍，PM₁₀含量增加1.29倍，说明保护原始戈壁地表不受破坏，是减少戈壁地区风沙灾害的重要手段之一。

The effect of dust storm on human living and production do not speak for themselves. Dust storm occurrence days decreased in recently 70 years， but it had been obviously increased since 2021， and attracted a lot of attentions. However， all the published papers were based on simulation or dust geochemistry， and almost no field data. We used field measurement of sand transport， PM₁₀ concentration and transported aeolian sediment grain size to explain the dust hazard in the dust sources during a strong dust storm. Our results indicated that： （1） Wind velocity was much larger in the dust sources than national weather station data. （2） PM₁₀ concentration can reach to 100 mg·m^-3， and is also larger than national measured data. （3） Sand transport reached to 10 kg·m^-1·h^-1， and dust can be transported longer distance. （4） The mean grain size of transported aeolian material was 0.07 mm， and coarse sand frequency can reach to 9%， and PM₁₀ frequency can reach to 8%. Coarse sand impacted on erodible land surface and caused more dust come into air and supplemented dust concentration in the sources. （5） Sand transport rate increased about 2 times， PM₁₀ concentration increased 2.90 time， and PM₁₀ frequency increased 1.29 time on disturbed land surface than undisturbed land surface， which means that protected gobi land surface can greatly decreased dust material during dust storm.