Grain-size analysis of a sediment core CW02 and surface sediments of the drainage area, retrieved from Chaiwopu Lake of Xinjiang, were carried out using a Malvern 2 000 grain-size analyzer. Combining with 137 Cs dating, a continuous high-resolution record of environmental changes was studied over the past 150 years. Firstly, according to primary components analysis of the contents of different grain-size, the material source of lake sediment was dis- cussed. It showed that the large particle fraction of lake sediment was from the drainage surface sediment. And then, environmentally sensitive grain-size components were extracted by the variations of the grain-size standard deviation. The results indicated that the content/mean-size of sensitive grain-size component (20 ~ 209 p~m) is sensitive to the regional sand-dust storm events in Chaiwopu lake basin. During the last 150 years, the strong sand-dust storm oc- curred during 1910--1930AD and 1980--2000AD. Historical documents also recorded the strong dust storms around 1910s and 1980s. Based on the analysis of the abrupt change points, the sediment grain-size increased abruptly a- round 1910AD, which indicated an abrupt environmental event.%通过对柴窝堡湖沉积物剖面和流域表层沉积物进行粒度分析,结合沉积剖面年代序列,研究了柴窝堡地区的环境演变与沙尘暴事件。首先通过主成分因子分析,对柴窝堡湖沉积物剖面粒度不同粒级组分含量进行了研究,探讨了湖泊沉积物的物质来源,获得了两个主控因子F1和F2,它们控制了湖泊沉积物近97.7%的粒度变化特征。研究表明,F2代表了以57μm为众数粒径的次总体,主要来源于地表风沙侵蚀;而F1为以7μm为众数粒径的次总体,主要受流水作用控制。进而通过粒径—标准偏差法,提取了湖泊沉积物中环境敏感粒度组分,风成组分C2（20～209μm）反映了区域风沙活动的历史,并揭示了1910—1930年和1980—2000年为百年来的两个沙尘暴相对活动强烈的时期。沉积物中记录的1980年和2000年左右的沙尘事件与器测记录及历史文献记载具有很好的一致性。最后利用均值突变诊断分析,发现柴窝堡湖地区1910年前后存在近百年来最强的沙尘事件,揭示了近百年来该地区一次最强的环境突变事件。
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