气象要素影响下雪冰离子淋溶过程研究——以乌鲁木齐河源1号冰川为例

为了更好地理解化学离子在雪坑中的迁移和保存，进一步解释冰芯记录，基于乌鲁木齐河源1号冰川海拔4130 m处的雪冰化学资料，研究了气温和降水与离子淋溶过程的关系.结果表明：气温与离子浓度呈负相关关系，夏季的雪坑离子浓度波动剧烈，冬季的雪坑离子浓度相对稳定.离子浓度随正积温的升高呈指数衰减趋势，当正积温至0℃以上时，离子浓度急剧降低；当正积温升至60℃左右时，离子浓度呈缓慢降低.不同离子的淋溶过程对正积温的响应有所不同，随着正积温的增加，SO₄^2-，NO₃^-，Na⁺，Cl^-，NH₄⁺和Ca²⁺的衰减趋势非常显著，而Mg²⁺和K⁺则呈现无规律性的变化.淋溶因子指出，融水渗浸作用导致雪坑中大部分离子被淋溶；不同离子的淋溶因子也有明显差异，Mg²⁺淋溶因子最小（0.43），SO₄^2-淋溶因子最大（0.84），说明Mg²⁺最为稳定，而SO₄^2-最易淋溶.降水对雪坑离子浓度的影响较为微弱，主要通过增加表层雪离子浓度而提升整个雪坑的离子浓度.

An investigation of the relationship between meteorological elements and the variation of ion concentration in snowpack:as an example of Ürümqi Glacier No. 1 in eastern Tianshan

We examine the impact of air temperature and precipitation on the chemical ionic concentration from successive snowpacks on ürümqi Glacier No.1 in eastern Tianshan,central Asia. Data suggest that the arrival of high temperatures has more impaction on ionic concentration in snowpack. Therefore,we establish the correla-tion between positive accumulated temperatures and ionic concentration. The results indicate that ion concentra-tions are exponential decline along with positive accumulated temperature in strong elution periods. During this process,ionic concentration reduced sharply at first,then,generally decreased as temperature rising proceeds until it dropped to the minimum. Elution Factor shows most of ions were leached out from snowpack after sum-mer melting at ürümqi Glacier No.1. The continuous precipitation could increase the ions concentrations in snow-pack through enhancing them in surface snow. However,the relationship is weak.