中文摘要：

利用石羊河流域上游、中游、下游当地气象站1961～2007年的冬季气温、降水、蒸发、最大冻土深度和1962—2008年沙尘天气的常规观测资料，分析了近47a石羊河流域冬季最大冻土深度和春夏沙尘日数的空间分布以及时间变化特征，近而采用相关系数法分析了冬季各气象因子与冬季最大冻土深度和次年春夏沙尘天气之间的相关关系，以进一步探讨石羊河流域冬季最大冻土深度与次年春夏沙尘天气的关系，结果表明：空间分布上，受地理位置和海拔高度等因素影响，石羊河流域冬季最大冻土深度分布呈东南一西北走向，而沙尘日数分布呈西北一东南走向，北部荒漠低海拔地区的冻土深度小于南部山区高海拔地区，而低海拔地区的沙尘日数明显高于高海拔地区。时间分布上，石羊河流域以及流域上、中游冬季最大冻土深度和沙尘日数线性趋势一致，皆随时间递减，在下游冬季最大冻土深度和沙尘日数线性趋势相反。相关系数法分析表明，石羊河流域冬季冻土深度与次年春夏沙尘天气发生日数之间都存在正相关，究其原因可能归根于冬季热力因子和水分因子对冬季最大冻土深度和次年春夏沙尘发生日数影响的一致性，其中热力因子的作用大于水分因子。

英文摘要：

Based on the meteorological sounding data of monthly air temperature, precipitation, evaporation, maximum frozen soil depth in winter over the upstream, middle stream and downstream of Shiyang river basin during 1961 ~ 2007, and sand-dust weather days in spring and summer over the upstream, middle stream and downstream of Shiyang river basin during 1962 - 2008, the temporal-spatial distribution characteristics of maximum frozen soil depth in winter ,sand-dust weather days from spring to summer are analyzed, further the relationships between maximum frozen soil depth and sand-dust weather days are also discussed. The results showed that spatial distribution of maximum frozen soil depth were decreased from southeast to northwest for influencing of altitude, geographical position and weather influence system, maximum frozen soil depth were more in high altitude areas than in low altitude areas. But sand-dust weather days were decreased from northwest to southeast, which is obviously more in low altitude areas than in high altitude areas. There are decrease trends of maximum frozen soil depth and sand-dust weather days over the up reaches and middle reaches of Shiyang river basin, and there are increase trends of maximum frozen soil depth and sand-dust weather days over the up reaches downstream of Shiyang river basin. There are positive intetTelations between sand-dust weather days and maximum frozen soil depth, the reason may be due to the winter thermodynamic and water factor effect on maximum frozen soil depth and sand-dust weather days are consistency, and the thermodynamic factor greater than water factors.