西坝镇高产农田浅层地下水水化学特征、 成因及水质分析

本研究以西坝镇高产农田区浅层地下水为研究对象，通过采用现场调研、室内实验、水化学分析和统计分析相结合的综合研究方法，分析了浅层地下水的水化学特征、成因及水质。结果表明：地下水中Ca2+、HCO- 3占主要优势，水化学类型为Ca-HCO3和Ca-SO4；NO- 3离子超标严重，超标点位占总取样点的66.7%，空间分布变化幅度大并出现局部的高浓度现象；研究区Ca2+、Mg2+与溶解性固体(TDS)呈高度线性相关、Ca2+和Mg2+呈高度线性相关和Ca2+和Mg2+与Cl-呈显著线性相关，地下水化学过程主要以风化-溶滤作用为主，化学类型主要形成作用为大气降水以及碳酸盐和硫酸盐的溶解；通过水质分析表明研究区浅层地下水不适合作为居民饮用水源，灌溉用水盐度危害中等偏高，建议对污染水体做处理后利用。

Hydrogeochemistry, Genesis and Waterquality Analysis of Shallow Groundwater of the High Yield Farmland in Xiba Town

Taking the shallow groundwater in the high yield farmland of Xiba town as the research object, based on the site investigation, laboratory experiment, hydrochemical analysis and statistical analysis, the hydrochemical characteristics, genesis and water quality of the shallow groundwater were analyzed. The results show that Ca2+ and HCO- 3 are dominant, hydrochemistry type by Ca-HCO3 and Ca-SO4 primarily. The concentration of NO- 3has exceeded seriously the standards, which account for 66.7% and the spatial distribution changed greatly and high concentration points appear in some area. A strong linear correlation is observed between TDS, Ca2+ and Mg2+, there is strong correlation between Ca2+ and Mg2+, Ca2+ and Mg2+ show significant linear correlation with Cl-. The main chemical process of groundwater is weathering and lixiviation. The formative action of chemical type is atmospheric precipitation and the dissolution of carbonate and sulfate. The analysis of water quality indicates that the shallow groundwater is not suitable for drinking, and the salinity of irrigation water is high, it is suggested to use the polluted water after treatment.