西宁市浅层地下水化学特征及形成机制  

Characteristics and Driving Mechanisms of Shallow Groundwater Chemistry in Xining City

作　　者：刘春燕[1,2] 于开宁 张英 荆继红[1,2] 刘景涛 LIU Chun-yan;YU Kai-ning;ZHANG Ying;JING Ji-hong;LIU Jing-tao(Institute of Hydrogeology and Environmental Geology,Chinese Academy of Geological Sciences,Shijiazhuang 050061,China;Hebei Key Laboratory of Groundwater Remediation,Shijiazhuang 050061,China;Hebei Center for Ecological and Environmental Geology Research,Hebei CE0 University,Shijiazhuang 050031,China)

机构地区：[1]中国地质科学院水文地质环境地质研究所,石家庄050061 [2]河北省地下水污染机理与修复重点实验室,石家庄050061 [3]河北地质大学河北省高校生态环境地质应用技术研发中心,石家庄050031

出　　处：《环境科学》2023年第6期3228-3236,共9页Environmental Science

基　　金：河北省高校生态环境地质应用技术研发中心开放研究基金项目(JSYF-Z202102);中国地质调查局项目(DD20221752-3,DD20190331)。

摘　　要：地下水是西部干旱地区重要的供水水源,随着西部大开发战略的深入,工业化和城市化发展加大了西宁市对地下水资源量的需求,不合理的开发利用已引起地下水环境发生变化,探明地下水化学演化特征及形成机制,对防止其恶化,确保可持续利用至关重要.运用水化学和多元统计技术相结合的方法,分析了西宁市地下水化学特征,探讨了地下水的形成机制和不同因子的影响程度.结果表明,西宁市浅层地下水化学类型多达36种,以HCO_(3)-Ca(Mg)(占比60.00%)和HCO_(3)·SO_(4)-Ca(Mg)(占比11.81%)为主,草地、林地和裸地中地下水化学类型5~6种,建设用地和耕地中地下水化学类型复杂,多达21种,表明受到人类活动影响较强.研究区地下水化学演化过程主要受岩石风化溶滤、蒸发结晶和阳离子交换作用综合影响,主要控制因素分别是水-岩相互作用(贡献率为27.56%)、工业废水排放(贡献率为16.16%)、酸碱环境(贡献率为16.00%)、化肥、农药的过量施用(贡献率为13.11%)和生活污水(贡献率为8.82%).针对西宁市地下水化学特征及其人类活动影响,提出了地下水资源开发利用方面的管控建议.Groundwater is one of the major sources of water supply,especially in the western arid regions.However,with the deepening of the western development strategy,industrialization and urbanization have increased groundwater resource demands in Xining City.Overexploitation and utilization have led to a series of changes in the groundwater environment.Identifying the chemical evolution characteristics and formation mechanism of groundwater is crucial for preventing its deterioration and ensuring sustainable use.By combining hydrochemistry and multivariate statistical techniques,the chemical characteristics of groundwater in Xining City were analyzed,and the formation mechanism of groundwater and the influence of different factors were discussed.The results showed that there were as many as 36 chemical types of shallow groundwater in Xining City,mainly HCO_(3)-Ca(Mg)(60.00%)and HCO_(3)·SO_(4)-Ca(Mg)(11.81%).There were 5-6 types of groundwater chemical types in bare land,grassland,and woodland.Groundwater chemical types in construction land and cultivated land were more complex,up to 21 types,indicating that they were strongly affected by human activities.The chemical evolution process of groundwater in the study area was mainly affected by rock weathering and leaching,evaporative crystallization,and cation exchange.The main controlling factors were water-rock interaction(contribution rate 27.56%)and industrial wastewater discharge(contribution rate 16.16%),acid-base environment(contribution rate 16.00%),excessive application of chemical fertilizers and pesticides(contribution rate 13.11%),and domestic sewage(contribution rate 8.82%).On account of the chemical characteristics of groundwater in Xining City and the influence of human activities,the management and control suggestions on the development and utilization of groundwater resources were put forward.

关 键 词：西宁市 地下水 水化学特征 形成机制 多元统计 控制因素 

分 类 号：X523[环境科学与工程—环境工程]