2014—2020年扬州市地下水水化学特征变化分析

Analysis of changes in groundwater hydrochemical characteristics in Yangzhou City from 2014 to 2020

为研究扬州市地下水水化学特征时空变化及其影响因素,综合应用多元统计分析法、Piper三线图解法、Gibbs图解法及离子比值法,对扬州市2014年和2020年地下水进行水化学特征变化分析。结果表明:2014年以来地下水水化学组分未发生明显变化,潜水阳离子以Ca^(2+)、Mg^(2+)、Na^(+)为主,阴离子以Cl^(-)和HCO_(3)^(-)为主;承压水阳离子以Ca^(2+)和Na+为主,阴离子以HCO_(3)^(-)为主。6年来水化学类型逐渐增多,种类更加多样化。水化学组分主要受岩石风化控制,潜水还受到蒸发-浓缩作用影响,少数地区亦受到阳离子交换影响。

To study the spatio-temporal variation of the chemical characteristics of groundwater in Yangzhou and its influencing factors,the multivariate statistical analysis method,Piper three-line graphical method,Gibbs graphical method and ion ratio method were used,the changes in hydrochemical characteristics of groundwater in Yangzhou in 2014 and 2020 were analyzed.The results show that the chemical composition of groundwater has not changed significantly since 2014.The main phreatic water cations are Ca^(2+),Mg^(2+)and Na+,the main anions are Cl^(-)and HCO_(3)^(-),and the main cations of confined water are Ca^(2+)and Na+,the anion is mainly HCO_(3)^(-).Over the past 6 years,the types of hydrochemistry have gradually increased and become more diversified.The hydrochemical composition is mainly controlled by rock weathering.Phreatic water is also affected by evaporation-concentration,and a few areas are also affected by cation exchange.