摘要
文章以地处“锰三角”的松桃河流域为研究对象,分别采集丰水期(5月)和平水期(9月)流域内可能的污染源及污染受体进行水样分析,通过因子分析探究影响松桃河流域地表水水化学特征的控制因素。结果表明:(1)EC和TDS呈现渣库渗滤液>垃圾填埋场渗滤液>“两井”>表层岩溶泉>地表水,Mn浓度总体呈现渣库渗滤液>“两井”>垃圾填埋场渗滤液>地表水>表层岩溶泉;地表水和表层岩溶泉中的氮素主要以NO_(3)^(-)-N的形式存在,“两井”、渣库和垃圾填埋场渗滤液氮素均以NH_(4)^(+)-N为主。地表水中氨氮超标率达到13%,Mn超标率为9.6%。(2)垃圾填埋场水化学类型呈SO_(4)·Cl-Na·K,锰渣库渗滤液水化学类型呈SO4-Mg型,地表水和表层岩溶泉水化学类型呈HCO_(3)-Ca·Mg型,“两井”地下水受到渣库渗滤液的影响,水化学类型向渣库渗滤液的方向演变,呈现出SO_(4)-Mg·Ca型。(3)地表水在丰水期表现出明显的雨季稀释作用,垃圾渗滤液部分指标表现出明显的淋滤作用,其他水体丰平两季水化学指标差异性较小。(4)影响研究区水化学特征的主要因素为地球化学作用、锰工业及生活污染,其中地球化学作用的影响最大,贡献率在53%左右,锰工业及生活污染占39%左右。虽然PCA和PMF分析尚不能准确区分锰工业和生活污染对研究区水环境污染的贡献率,但通过与表层岩溶泉水化学特征的结合比对以及松桃河Mn和氨氮沿程变化,指示地表水仍然受到锰渣库和生活污染,对松桃河流域涉锰工业企业、渣库和生活污染的治理工作仍需继续。
The counties of Xiushan inChongqing,Songtao in Guizhou,and Huayuan in Hunan are home to the enterprises producing Electrolytic Manganese Metal(EMM)in China and form China's"Manganese Triangle".Although the development of the manganese industry has driven economic growth,it has also caused significant ecological and environmental damage.Statistically,the production of 1 ton of EMM generates 6 tons to 10 tons of electrolytic manganese slag.The leachate from fresh slag is acidic(pH≈5)and contains high concentrations of ammonia nitrogen(565 mg·L^(-1)to 792 mg·L^(-1)),manganese(936 mg·L^(-1)to1,460 mg·L^(-1)),and sulfate(9,250 mg·L^(-1)to 11,400 mg·L^(-1)).Additionally,the leachate contains high levels of ions such as nitrogen(N),phosphorus(P),potassium(K,and magnesium(Mg).Rainfall and surface water can dissolve these soluble components,facilitating their migration into the environment.However,due to inadequate anti-seepage measures and complex geological conditions,the leachate has not been fully collected and treated,leading to contamination of surrounding soils and surface water bodies.Hence,to better understand the impact of the manganese industry on the environment,this study investigated the hydrochemical characteristics and pollution patterns in the Songtao River Basin.Water samples from potential pollution sources and receptors were collected during both the rainy season(May)and the dry season(September),respectively.Principal Component Analysis(PCA)and Positive Matrix Factorization(PMF)were used to identify the controlling factors affecting the hydrochemical characteristics of surface water in the study area.The findings are as follows:(1)Electrical Conductivity(EC)and Total Dissolved Solids(TDS)exhibited the following decreasing trend:leachate from manganese slag yard>landfill leachate>polluted groundwater from two wells>surface karst spring>surface water.Mn concentrations generally followed the order:leachate from manganese slag yard>polluted groundwater from two wells>landfill leachate>surface water>surface karst spring.The nitrogen in surface water and surface karst springs primarily existed in the form of NO_(3)^(-)N,while in other instances,nitrogen mainly appeared as NH_(4)^(+).In surface water,NH and Mn concentrations exceeded 13%and 9.6%of the permitted levels,respectively.(2)the pH of the landfill leachate had a pH above eight,and the chemical composition included SO.CI-NaKIn contrast,the leachate from the manganese slag yard exhibited a pH value ranging from weakly acidic to neutral(pH 4.64 to 7.17),with a chemical composition of SO_(4^(-))-Mg.The surface water and surface karst spring water were dominated by HCO_(3)^(-),Ca^(2+),Mg^(2+)type water.Interestingly,the polluted groundwater from two wells,although classified as groundwater,exhibited a SO_(4^(-))Mg.Ca type due to the influence of the leachate from manganese slag.(3)in the rainy season,surface water demonstrated substantial dilution effects,whereas specific indicators within waste leachate exhibited a significant percolation.Meanwhile,chemical indicators in other water bodies exhibited minimal variation between the rainy and dry seasons.(4)both PCA and PMF extracted four main influencing factors,identifying geochemical processes,the manganese industry,and domestic pollution as the primary contributors to the hydrochemical characteristics.Factor 1(F1)in PCA and Factor 4(F4)in PMF exhibited consistent patterns,primarily associated with HCO_(3)^(-),Ca^(2+),Mg^(2+),and TDS.These factors represent the combined effects of geochemical processes,with an average contribution rate of 52.99%.F4 in PCA aligned closely with Factor 3(F3)in PMF,where Mn as the dominant loading variable,indicated pollution from the manganese industry,contributing an average of 5.06%.F3 in PCA and F1 in PMF,characterized by K^(+),Cl^(-),and Na^(+),represented domestic pollution,with an average contribution rate of 16.44%.However,due to the overlapping signatures of pollutants from both manganese industrial emissions and domestic sources,neither method can accurately quantify the individual contribution rates of these two pollution sources to the contamination of the water environment in the study area.By comparing the chemical compositions of surface karst springs,and according to the synchronous trends of manganese and ammonia nitrogen concentrations along the Songtao River,it can be inferred that surface water continues to be affected by both manganese slag storage and domestic pollution.This highlights the need to sustain and strengthen remediation efforts targeting manganese-related industrial activities,slag yards,and domestic pollution in the Songtao River Basin.Additionally,localized monitoring of manganese and ammonia nitrogen should be enhanced to identify pollution pathways and prevent untreated leachate from slag yards and other pollution sources from being directly discharged into surface water.Furthermore,stricter supervision and regulation of domestic pollution discharges are essential to ensure that domestic sewage and pollutants are not released untreated into surface water.
作者
龚效宇
张重乾
黎伟
谢蔚嵩
朱令
徐磊
叶樑锴
张少剑
王程程
朱彬
安思危
黄代宽
GONG Xiaoyu;ZHANG Zhongqian;LI Wei;XIE Weisong;ZHU Ling;XU Lei;YE Liangkai;ZHANG Shaojian;WANG Chengcheng;ZHU Bin;AN Siwei;HUANG Daikuan(Guizhou Institute of Environmental Science Research and Designing,Guiyang,Guizhou 550009,China)
出处
《中国岩溶》
北大核心
2025年第3期462-476,共15页
Carsologica Sinica
基金
贵州省科技计划项目(黔科合基础−ZK【2022】一般238)
贵州省科技计划项目(黔科合支撑[2023]一般182)
贵州省科技厅环境科技项目(2121-03)。
关键词
松桃河流域
锰
氨氮
渣库渗滤液
水化学
PCA分析
PMF分析
the Songtao River Basin
manganese
ammonia nitrogen
leachate from slag yards
hydrochemisty
PCA analysis
PMF analysis
作者简介
第一作者:龚效宇(1994-),女,工程师,硕士研究生,长期从事水文地球化学及水环境污染研究。E-mail:15387497230@163.com。;通信作者:黄代宽(1981-),男,正高级工程师,博士研究生,长期从事环境污染治理。E-mail:63523227@qq.com。
