新疆巩乃斯河流域季节性积雪中硫酸盐的时空分布与来源

SOURCES AND TEMPERAL-SPACIAL CHANGES OF SULPHATE IN SEASONAL SNOW COVER IN THE KUNNES RIVER VALLEY, CHINA

1996～1997年冬季，一次针对巩乃斯河流域季节性积雪化学成分的调查与研究工作得以开展，其间共采集了约100个新、老雪样。经室内分析发现巩乃斯河流域季节性积雪中含有相对丰富的硫酸盐。本文主要分析了该流域季节性积雪的SO4^(2-)离子以及与之有关的K^+＋Na^+和Ca^(2+)离子的时间与海拔分布特征，并重点讨论了硫酸盐类物质的来源。

Kunnes River is one of the Tributaries of Yili River in Xinjiang. In spring of 1996 andwinter of 1996/1997, snow chemical surveys were carried out here. About 100 snow andriver water samples were collected along the river-Then, the samples were analyzed bymethods of common chemical analysis and IDMS in Xinjiang institute of Geography. Theresults showed that concentration of the Ca^(2+) varies in a range from 2 to 12 mg/L, andthat of Mg^(2+) is between 0. 9 and 2. 5 mg/L. The concentration of K^+ ＋Na^+ changes from4. 4 to 8. 76 mg/L. Especially, a relative high concentration of sulphate is found in thesnow. By analyzing the data of chemical survey of snow cover in Kunnes River valley care-fully, it can conclude that the sulphate is mainly from the dried lakes and desert in centralAsia. It is also found that there are temporal and spatial changes of sulfate content in theseasonal snow cover. The reasons for temporal changes of sulfate content in the seasonalsnow cover may be the result of variance of snow cover in central Asia. Generally, thearea of snow cover is large in the midwinter and small in the early winter and spring. Con-sequently , the dust blowing up into the air from the earth surface is more in the early win-ter and spring. The dust will deposit onto the suriace of the snow cover in form of dry de-position and/or falling down with the snow crystal. There are also obvious influences of lo-cal anthropogenic factors on the snow chemistry.