永定河补水地下水质量评价及时空变化特征  

Evaluation and spatial-temporal variation characteristics of groundwater quality during water replenishment to Yongding River

作　　者：陈吉吉 陶蕾 刘保献 席玥 徐蘇士 荆红卫 CHEN Jiji;TAO Lei;LIU Baoxian;XI Yue;XU Sushi;JING Hongwei(Beijing Ecological Environment Monitoring Center,Beijing 100048;State Environmental Protection Key Laboratory of All Materials Flux in Rivers,Beijing 100871,China)

机构地区：[1]北京市生态环境监测中心,北京100048 [2]国家环境保护河流全物质通量重点实验室,北京100871

出　　处：《干旱区资源与环境》2023年第9期118-125,共8页Journal of Arid Land Resources and Environment

基　　金：北京市科技重大专项项目(Z181100005518009);北京市重点流域地表水高密度监测网络建设项目资助。

摘　　要：以永定河补水地下水水样测试结果为基础,采用不同水质评价方法对补水期间永定河沿岸地下水进行质量评价,根据补水期间各采样井参评指标的PCA(Principal Component Analysis)降维处理结果,筛选最适评价方法,并进行研究区域地下水水质时空变化分析。结果表明:从参评指标关注度、水质类别分布连续性、评价结果与水质变化情况一致性等方面考虑,模糊综合评判法的取小取大算子能够更准确的反映补水期间永定河沿线地下水水质的优劣变化。短期内生态补水未对研究区域地下水水质空间分布特征产生影响。与地表水水力联系密切的上游河段水质最好;下游河段次之,整体表现出Fe、Mn等背景指标浓度偏高的现象;中游河段水质较差,人为污染指标NO-3-N浓度偏高。受扩散稀释作用的影响,随着补水工作的进行,研究区域Ⅴ类井(NO^(-)_(3)-N高值区)消失,水质整体向中间水质Ⅲ类水过渡。Groundwater samples from 12 monitoring wells along the Yongding River during the three stages of spring water replenishment,the end of water replenishment,and autumn water replenishment in 2020 were taken as the basic data,and multiple water quality assessment methods were used to evaluate the quality of groundwater.According to the dimensionality reduction results of Principal Component Analysis(PCA)of each sampling well during water replenishment,the optimal evaluation method was selected,and the spatio-temporal changes of groundwater quality along the Yongding River were analyzed.It was found that the small and large operator of fuzzy comprehensive evaluation method could more accurately reflect the change of groundwater quality along Yongding River during the replenishment period,which considering the importance of evaluation indexes,the continuity of distribution of water quality categories,and the consistency of evaluation results and water quality changes.Ecological water replenishment didn't influence the spatial distribution characteristics of groundwater in the receiving area in the short term,and the water quality in upper reaches with close hydraulic connection with surface water was the best.The water quality in the lower reaches of the river was the second,and the concentration of Fe,Mn and other background indicators were higher on the whole.The water quality in the middle reaches was poor,and the concentration of NO;-N,the man-made pollution index,was high.Affected by diffusion dilution,with the implementation of water replenishment,class V wells(high value area of NO^(-)_(3)-N)in the study area disappeared,and the overall water quality transitioned to intermediate category,class II.

关 键 词：永定河补水 地下水质量评价 PCA降维 水质时空变化 

分 类 号：P641[天文地球—地质矿产勘探]