Analysis on Wind Regime and Wind Borne Sand Potential in a Desert-oasis Ecotone——A Case Study in Qira County,Xinjiang

The Desert-oasis ecotone in southern marginal zone of the Taklimakan Desert is one of the areas with the severest desertification in China.In this study a statistical analysis on wind regime and wind borne sand potential in Qira County located in the southern marginal zone of the Taklimakan Desert was carried out during the period from 2005 to 2006.The results are as follows:(1) Wind direction in the study area is dominated by W,its occurring frequency varies in a range of 62.43%~76.25%,and then by WNW with an occurring frequency of 17.75%;(2) Sand-raising wind in the study area occurs mainly in spring and summer,its occurring frequency varies in a range of 11.93%~61.84%,especially in June,the mean sand-raising wind velocity in spring and summer is higher than that in autumn and winter,and its maximum can be up to 7.90 m/s;(3) During sand drift,the variability index(RDP/DP) of wind direction in this region is as high as 0.95,the wind environment is in a single-peak form,the resultant sand drift potential(RDP) and resultant sand drift direction(RDD) are 27.98 VU and 92.10°ESE respectively,and these reveal that this region belongs to a low wind-energy environment according to Fryberger's(1979) classification.The seasonal variation extent of sand drift potential is high,especially in spring and summer.It is necessary for the local government to take some measures to conserve the natural vegetation so as to reduce wind velocity and protect environment.