三峡库区城市浅层地下水水化学和氢氧稳定同位素特征及其指示意义  

Hydrochemical and hydrogen-oxygen stable isotope characteristics of urban shallow groundwater in Three Gorges Reservoir Area and indicative significance

作　　者：范祖金 魏兴 周育琳 李佳文 申纪伟[1] FAN Zujin;WEI Xing;ZHOU Yulin;LI Jiawen;SHEN Jiwei(College of Civil Engineering,Chongqing Three Gorges University,Chongqing 404100)

机构地区：[1]重庆三峡学院土木工程学院,重庆404100

出　　处：《环境科学学报》2023年第6期258-269,共12页Acta Scientiae Circumstantiae

基　　金：重庆市自然科学基金项目(No.CSTB2022NSCQ-MSX1392);重庆市教委科学技术研究项目(No.KJQN202201224、KJQN202101235)。

摘　　要：浅层地下水作为三峡库区万州区居民生活和工农业生产用水的主要来源,是维持该区经济可持续发展和生态环境稳定的重要保障.为探究三峡库区万州区浅层地下水化学组分控制因素和补给来源,综合运用Piper三线图、Gibbs图、离子比例关系、相关性分析和同位素技术等方法,对浅层地下水水化学和氢氧稳定同位素特征进行分析.结果表明:(1)研究区长江流域(CJ)和非长江流域(FCJ1、FCJ2和FCJ3)浅层地下水均为弱碱性淡软水,阴阳离子均以HCO_(3)^(-)、Ca^(2+)为主,CJ和FCJ1流域浅层地下水水化学类型以HCO_(3)^(-)Ca型为主,其次为Cl-Ca型和SO_(4)·Cl-Ca·Mg型,FCJ2流域浅层地下水水化学类型均为HCO_(3)^(-)Ca型,FCJ3流域浅层地下水水化学类型以HCO_(3)^(-)Ca型为主,其次为SO_(4)·Cl-Ca·Mg型.(2)研究区浅层地下水化学组分主要受岩石风化控制,其次还受大气降雨、阳离子交换作用以及人类活动影响,其中4个流域的阳离子交换作用存在差异,CJ和FCJ2流域发生的阳离子交换作用较强,FCJ1流域发生的阳离子交换作用较弱,FCJ3未发生明显的阳离子交换作用;4个流域浅层地下水主要离子来源受硅酸盐岩、碳酸盐岩和盐岩溶滤影响,CJ和FCJ1流域浅层地下水中SO_(4)^(2-)来源受工矿活动影响,FCJ3流域浅层地下水中SO_(4)^(2-)可能来源于芒硝溶滤.(3)研究区浅层地下水补给来源以大气降雨为主,其中在大气降雨补给浅层地下水的过程中,CJ、FCJ1和FCJ3受非平衡蒸发作用影响较小,而FCJ2流域受非平衡蒸发作用影响到较大;4个流域的浅层地下水未受到明显的蒸发作用影响.该研究结果可为三峡库区万州区地下水资源的合理开发利用与经济圈建设提供科学依据.As the main water source for residents living and industrial and agricultural production in Wanzhou District of Three Gorges Reservoir Area,shallow groundwater is an important guarantee for maintaining sustainable economic development and ecological environment stability in this area.In order to explore the control factors and recharge sources of chemical components in Wanzhou District,the hydrochemical characteristics of shallow groundwater and hydrogen and oxygen stable isotopes were analyzed by using Piper diagram,Gibbs diagram,ion ratio relationship,correlation analysis and isotope technology.The results show that:①The shallow groundwater in the Yangtze River Basin(CJ)and non-Yangtze River Basin(FCJ1,FCJ2 and FCJ3)in the study area is weakly alkaline and soft water,and the anions and cations are mainly HCO_(3)^(-)and Ca^(2+).The hydrochemical type of shallow groundwater in CJ and FCJ1 basins is mainly HCO_(3)^(-)Ca type,followed by Cl-Ca type and SO_(4)·Cl-Ca·Mg type.The hydrochemical type of shallow groundwater in FCJ2 basin is HCO_(3)^(-)Ca type,and the hydrochemical type of shallow groundwater in FCJ3 basin is mainly HCO_(3)^(-)Ca type,followed by SO_(4)·Cl-Ca·Mg type.②The chemical composition of shallow groundwater in the study area is mainly controlled by rock weathering,followed by atmospheric rainfall,cation exchange and human activities.There are differences in cation exchange in the four basins,the cation exchange in the CJ and FCJ2 basins is strong,the cation exchange in the FCJ1 basin is weak,and the cation exchange in FCJ3 is not obvious.The main ion sources of shallow groundwater in the four basins are affected by silicate rock,carbonate rock and salt karst filtration,the source of SO_(4)^(2-)in shallow groundwater of CJ and FCJ1 basins is affected by industrial and mining activities,SO_(4)^(2-)in shallow groundwater of FCJ3 basin may come from mirabilite leaching.③The source of shallow groundwater recharge in the study area is mainly atmospheric rainfall.In the process of atmospheric r

关 键 词：浅层地下水 水化学 控制因素 离子来源 氢氧稳定同位素 三峡库区万州区 

分 类 号：X523[环境科学与工程—环境工程]