松嫩平原西部地下水氟和砷的富集机理与动态变化特征  

Enrichment mechanism and dynamic variation characteristics of fluorine and arsenic in groundwater of western Songnen Plain

作　　者：邓远东 冶雪艳 吴亚敏[1,2] 杜新强 DENG Yuan-dong;YE Xue-yan;WU Ya-min;DU Xin-qiang(College of New Energy and Environment,Jilin University,Changchun 130021,China;Key Laboratory of Groundwater Resources and Environment,Ministry of Education,Jilin University,Changchun 130021,China)

机构地区：[1]吉林大学新能源与环境学院,长春130021 [2]吉林大学地下水资源与环境教育部重点实验室,长春130021

出　　处：《中国环境科学》2023年第10期5377-5390,共14页China Environmental Science

基　　金：国家自然科学基金资助项目(41972247)。

摘　　要：为揭示松嫩平原西部地下水中氟和砷的演变趋势,以通榆县为典型研究区,系统开展地下水氟和砷浓度现状调查,利用离子比图、自组织映射网络等方法进行水质数据分析.结果表明:潜水氟含量受含水介质沉淀溶解作用的制约,蒸发浓缩作用对大部分浅层高、低氟地下水形成都有一定影响,但并非高氟地下水形成的主导作用.水中铁、锰氧化物的溶解促进浅、深层地下水As的解吸释放.1995年以来区内中东部浅层地下水氟浓度整体水平有所降低,可能与当地大规模开发地下水所导致的地下水位下降、蒸发减弱等因素有关;虽然深层高氟地下水浓度变化不大,但分布范围扩大,可能与浅层高氟地下水经破损井管道渗漏进入承压含水层有关.1995~2021年区内中部与东北部浅层地下水砷浓度整体水平远高于世卫组织饮用水的指导值(10μg/L),虽然深层高砷地下水浓度变化不大,但较浅层地下水高砷区分布更广、富集区更多、污染更严重,这可能与承压含水层的还原条件促进砷的释放有关.因此,通榆县深层地下水的开采,需要避开地下水高砷污染区,且需要合理确定开采水平避免劣质水入侵;同时也要关注开采井止水和开采井的破坏导致的串层污染问题.In order to further reveal the the evolutionary trends of fluorine and arsenic in groundwater in the western part of the Songnen Plain,a comprehensive investigation was conducted on the current condition of fluorine and arsenic concentrations in groundwater,focusing on Tongyu County as a case study.Water quality data were analyzed using ion-ratio diagrams and self-organizing mapping networks.The results show that fluorine content of the phreatic water was governed by the precipitation and dissolution of the water-bearing medium,and evaporation and concentration had a certain influence on the formation of most of the shallow,high and low fluoride groundwater,but were not the dominant role in the formation of high fluoride groundwater.The dissolution of iron and manganese oxides from water promoted the release of As from shallow and deep groundwater.The overall level of the fluoride concentration in shallow groundwater in the mid-eastern part of the region has decreased since 1995,which may be attributed to factors such as the depletion of groundwater levels and decreased evaporation resulting from extensive local groundwater extraction.Although the deep,high fluoride groundwater did not show a significant change,its spatial coverage has expanded;This may be related to the leakage of shallow,high fluoride groundwater into the pressurized aquifers through the broken well pipes.The overall concentrations of arsenic in shallow groundwater in the central and northeastern regions from 1995to 2021 significantly exceed the WHO guideline values for drinking water.Although the concentrations of high-arsenic groundwater in deeper layers have remained relatively stable,they exhibit a wider distribution,more enriched zones,and greater contamination compared to high arsenic zone in shallow groundwater.This may be related to the reducing conditions in the pressurized aquifer that promoted the release of arsenic.Therefore,the exploitation of deep groundwater in Tongyu County should be conducted with cautions,taking into considera

关 键 词：高氟地下水 高砷地下水 富集机理 动态变化 

分 类 号：X52[环境科学与工程—环境工程]