毛乌素沙地风况及输沙势特征

利用毛乌素沙地腹地野外实测风速风向数据，系统分析了毛乌素沙地的起沙风和输沙势的变化特征。结果表明：（1）毛乌素沙地的起沙风和输沙势主要分布在NW、NNW和N等3个方位。（2）毛乌素沙地春季（3—5月）起沙风频率和输沙势最大，分别占全年的46.23%和52.97%。（3）起沙风频率的日内变化呈单峰曲线：16：00起沙风频率最大，为22.11%。起沙风平均风速的日内变化呈双峰曲线：00：00起沙风平均风速最大，为7.84 m·s^-1；14：00起沙风平均风速为7.63 m·s^-1，是次峰值。（4）毛乌素沙地年输沙势为66.75 VU，按照Fryberger风能环境划分标准，属于低风能环境；方向变率指数RDP/DP为0.51，中比率，钝双峰风况，其中偏北峰值远大于偏南峰值。

Characteristics of Wind Regime and Drift Potential in Mu Us Sandy Land

Based on the field measured wind velocity and direction data in the hinterland of Mu Us Sandy Land, this paper systematically analyzed the variation characteristics of the sand-driving wind and drift potential in Mu Us Sandy Land. The results show that:(1) The sand-driving wind and drift potential in Mu Us Sandy Land were mainly distributed in NW, NNW and N directions. (2) The frequency of sand-driving wind and drift potential in Mu Us Sandy Land between April and May were the largest, accounted for 46.23% and 52.97% of the annual total, respectively. (3) The diurnal variation of the sand-driving wind frequency was unimodal, and the peak value was 22.11% at 16:00. The diurnal variation of the average wind speed showed a bimodal curve:the peak value was 7.84 m·s^-1 at 00:00, and the secondary peak value was 7.63 m·s^-1 at 14:00. (4) The annual drift potential in Mu Us Sandy Land was 66.75 VU, which belonged to the low wind energy environment according to Fryberger's categorization standard of wind energy environment. The RDP/DP was 0.51, which belonged to medium ratio and obtuse bimodal wind condition, and the north peak value was much stronger than the south peak value.