布古里沙漠部分地区风沙环境特征分析

Characteristics of blow sands environment in Buguli Desert

布古里沙漠位于喀什绿洲和叶尔羌河绿洲之间，具有独特的地貌特征和风沙环境特征。通过对布古里沙漠部分地区的气象资料分析和野外实地风沙观测，对其风沙环境特征进行了分析。结果表明：布古里沙漠的沙粒平均粒径是0．16mm，起沙时间集中在每年的4～9月，风向主要是西北风和东北风，偏西北风略强；在2m高处测量的裸露沙面起动风速的是3．0m／s，植被覆盖率为7％，起动风速为5．2m／s，植被覆盖率为14％，起动风速为6．8m／s；当平均风速为6．7m／s时，气流输运沙子主要在近地表面0～10cm，风沙流中含沙量随垂直高度呈指数衰减，给出了风沙流的含沙量随垂直高度分布的相关方程和参数。

Located between Kashgar oasis and Yarkand Oasis range of 38°27′12″-39° 14′48″N, 76°23′9″-77°24′13″E）, the , whose area is approximately 34.3 × 10^4 hm2 （in the Buguli Desert has several unique topographical fea- tures and aeolian environment characteristics. According to the analysis of Yuepuhu Meteorological Observatory, data observed from some areas of the Buguli desert, on the condition of 11.4 m-altitude the wind speed up to 6 m/s, the wind characteristics were analyzed by means of the statistical method in the Buguli Desert. Collecting sand sample from the Buguli desert （77°1′14″E, 39°2′29″N）, the grain size characteristics of sand were analyzed. For field observations and measures of threshold velocity of drifting sand in sandstorm, vertical lattice sand collector was used to collect the sediment load of sand flow and the structural characteristics of drifting sand studied. The several prelimi- nary conclusions were presented as follows：most of sandstorms occur from April to September, the wind direction is mainly northwest and northeast and the west-northwest wind is a little stronger, average particle size of sand in the Buguli Desert is 0.162 mm. The threshold velocity of drifting sand at 2 m high on the bare sand surface is 3.0 m/s, which is much smaller than that of sand surface covered by vegetation （5.2 m/s）, the vegetation coverage rate is only of 7%. When the vegetation coverage rate is up to 14%, the threshold velocity of drifting sand is up to 6.8 m/s. When the average wind speed reaches 6.7 m/s, the pneumatic transportation sands are all close to the ground （about 0-10 cm high） and sand stream sediment concentration decays exponentially with the vertical height increase. A related vertical distribution equation and parameter of sand stream sediment concentration of drifting sand was.put out.