南极长城站地区西湖水化学组成影响因子分析

FACTORS INFLUENCING THE CHEMICAL COMPOSITION OF XIHU LAKE NEAR THE GREAT WALL STATION,ANTARCTICA

在对南极长城站地区西湖水化学组成影响因素分析的基础上，利用化学风化反应平衡方程，对西湖水化学组成的影响因子进行了定量化分析评价。研究表明，影响西湖水化学组成的主要因素是大气降水、化学风化过程和海洋物质的叠加效应。西湖水中Ｃａ和Ｍｇ元素主要来源于陆地原生矿物的化学风化，尤其是碳酸盐风化；Ｎａ和Ｋ元素则主要来源于海洋物质的叠加效应。硅（铝）酸盐风化产生的元素量对湖水的贡献率较小，反映出在南极低温条件下化学风化尚停留在硅（铝）酸盐脱盐基阶段。

 On the basis of qualitative analysis of the factors influencing the aquatic chemical composition of Xihu Lake,the equilibrium equation for chemical weathering is employed to quantitatively evaluate these factors. The results show that atmospheric precipitation,chemical weathering and oceanic material all contribute to the chemical composition of Xihu Lake. Ca and Mg come from the chemical weathering of minerals,especially of silicate while Na and K are controlled mainly by oceanic material. The less contribution of silicate weathering to the chemical composition of Xihu Lake demonstrates that chemical weathering is at the stage of decationizing.