中文摘要：

西昆仑山位于塔克拉玛干沙漠南缘。从海拔6530m钻取的崇测冰帽冰芯发现，20世纪90年代前的60多年间，沙尘沉积和年积累率存在着一致的下降性趋势变化。结合对沙尘源地、沙尘输送路径及其沉积特征的调查研究，分析源——汇的诸多影响因素，探讨影响高海拔地区降水的主导过程，结果表明：1）在高海拔地区，尘埃可能比低海拔地区对降水起着更为重要的作用，这种作用主要是通过凝结核数量的变化发生的；2）在高海拔地区降水形成过程中，悬浮的尘埃数量会直接影响凝结核的数量；3）对于塔克拉玛干沙漠周边这样的干旱环境，大气水汽供应在高海拔地区相对更为充分些，因此与低海拔地区相比，高海拔山地冰川上的降水过程对大气尘埃微粒浓度的变化似乎更为敏感；4）在沙漠及其周边地区的盛行气候条件下，冰川冰雪积累呈现出逐渐减少的趋势，与沙漠地区气候和环境变化密切相关——过去几十年间塔克拉玛干低海拔区降水增加，沙尘减少；5）这种行将持续的趋势可能会通过大气尘埃的变化继续影响高海拔冰川的物质平衡。本研究的这一发现可能从一个侧面揭示了一些地区性冰川变化的原因，如中亚地区持续了几十年的冰川消退现象。

英文摘要：

The coherent variations of annual snow accumulation rate and dust deposition over 60 years are recorded in an ice core drilled at 6530m asl （meters above sea level） on the Chongce ice cap, located in the West Kunlun Mts. south of the Taklimakan Desert in China. These records were investigated in the context of both the dust transport pathways from the source region and of climatic changes in this arid environment. The factors relating the dust transport from the source to sink area were taken into account to ascertain the integration of these factors on the pre- cipitation-forming process at high elevations. Results indicate that： 1 ） dust is predominant among aerosols in precipitation at high altitude ;2）the dust aerosol population may be more instrumental than the vapor supply in the formation of precipitation at such altitudes ;3 ） compared to low-elevation glaciers, the accumulation of snow on high moun- tain glaciers seems to be more sensitive to changes in the concentration of air burden dust particulates, which are closely related to the climatic variations around the desert region;and 4）under the current climate conditions surrounding the desert region, the decreasing trend in snow accumulation, in concert with the decrease in dust deposition that has occurred over the past several decades, might continue. This effect on snow accumulation at high altitudes may explain one of the potential elements responsible for the longer-term glacial variation,i, e. the glacial retreat that has lasted for decades in Middle Asia.