Aeolian dusts are common in Tarim Basin. The analyzed results show that the concentration of sand-dustaerosol in the atmosphere is much higher during aeolian dusts than that during the periods without aeolian dusts. Duringaeolian dusts, the percentage by weight of the fine particles in the atnosphere decreases over the Cele station butincreases over the Aksu station due to the difference of the geographical locations. This proves that the fine materials areabundant in the sand-dust source regions and they are easy to be carried into the atmosphere to be as the main sources ofthe sand-dust aerosol during aeolian dusts. The curves of spectrum distribution of Al and other elements in theatmospheric aerosol over the Aksu station are unimodal, and the maximum values of the concentration vary in a range of4.7 ～ 7.0 μm, which prove that the atmospheric aerosol particles over the locality are mainly from the local sand-dustsources. The analysis on the richly concentrating factors shows that the concentrations of all the crust elements in theatmosphere over the Aksu and Cele stations are higher during the aeolian dusts than that during floating dusts and in thebackground atmosphere. Moreover, the lower the visibility is, the higher the proportion will be, and the concentrations ofthe crust clements in the atmosphere are high during all the aeolian dusts.%沙尘天气是塔里木盆地区常见的天气现象,对大气沙尘气溶胶的分析表明,沙尘暴期间,沙尘气溶胶浓度远大于非尘暴期间.对策勒和阿克苏两地的比较分析表明,由于两地地理环境的差异,沙尘暴期间,策勒站细颗粒质量百分比呈下降趋势;阿克苏站细颗粒质量百分比呈上升趋势,说明尘暴期间由于当地沙尘源丰富,细粒物质较多,细粒物质迅速被携带到高空,成为沙尘气溶胶的主要来源.阿克苏站大气气溶胶中Al等元素在不同高度的谱分布呈单峰型,浓度最大值出现在4.7μm～7.0μm范围内,说明当地大气气溶胶颗粒主要来源于地表沙源.富集因子分析表明,阿克苏站和策勒站沙尘暴和扬尘天气的各地壳元素含量均高于浮尘和背景大气,而且能见度能见度愈小,高出的比例愈大;各种沙尘天气发生时,均以亲地元素的浓度为最高.
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