北京市景观用水DOC荧光特性及其与铜、铅的络合特性研究  

Fluorescence Characteristics of DOC for Landscape Water in Beijing and Its Complexing Characteristics with Copper and Lead.

作　　者：许新瑶 蒲晓[1] 高静 董雪 张玉虎[1] 胡延佳 孟少康 王健 XU Xin-yao;PU Xiao;GAO Jing;DONG Xue;ZHANG Yu-hu;HU Yan-jia;MENG Shao-kang;WANG Jian(School of Resources Environment&Tourism,Capital Normal University,Beijing 100048,China;Safety and Environmental Management Headquarters of Tsingtao Brewery Co.Ltd.,Qingdao 266071,China)

机构地区：[1]首都师范大学资源环境与旅游学院,北京100048 [2]青岛啤酒股份有限公司安全环保管理总部,山东青岛266071

出　　处：《生态与农村环境学报》2022年第4期521-530,共10页Journal of Ecology and Rural Environment

基　　金：北京市自然科学基金(8172015);北京市教委科研计划(KM201810028013)。

摘　　要：选取北京市4个公园(南海子公园、圆明园、陶然亭公园和龙潭公园)的景观用水作为研究对象,分析水体DOC的荧光组分和分子量分布特征,并对不同分子量DOC与Cu^(2+)、Pb^(2+)分别进行荧光猝灭滴定实验,确定络合态重金属含量、参与络合的荧光组分、络合参数等,以表征不同重金属离子与DOC的络合特性。结果显示,北京市4个公园水体DOC中鉴定出3种荧光组分,其中C1和C2为类腐殖质物质,C3为类蛋白色氨酸类物质。对DOC进行分子量分级,分级后DOC中鉴定出2种荧光组分,其中C1为类腐殖质物质,C2为类蛋白质色氨酸物质。荧光猝灭滴定实验后,<1 kDa DOC形成的络合态重金属含量最多,与Cu^(2+)、Pb^(2+)络合时的络合稳定常数也最大。络合形成的DOC-Pb浓度(16.91~99.15μmol·L^(-1))大于DOC-Cu(12.42~95.99μmol·L^(-1)),但Cu^(2+)对组分C1、C2的猝灭程度和络合稳定常数均强于Pb^(2+)。Cu^(2+)对组分C1的猝灭作用强于C2,表明Cu^(2+)更倾向于与类腐殖质组分络合,而Pb^(2+)则没有明显倾向性。研究结果可为北京市景观水体的水质维护和潜在污染治理提供指导。The landscape water in four parks in Beijing(Nanhaizi Park,Yuanmingyuan,Taoranting Park,and Longtan Park)was selected as the research objects to analyze the fluorescence composition and molecular weight distribution characteristics of the water DOC.Fluorescence quenching titration experiments were performed on DOC with different molecular weights and Cu^(2+),Pb^(2+),for determining the contents of complexed heavy metals,the fluorescent components involved in the complexation,and the complexing parameters and for showing the complexing characteristics of different heavy metal ions with DOC.The results show that three fluorescent components were identified in the DOC of Beijing′s landscape water bodies,among which C1 and C2 representing humus-like substances,and C3 representing protein-like tryptophan substances.After grading the molecular weight of DOC,it was found that two fluorescent components were identified in the classified DOC,including the humus-like component C1 and the protein-like tryptophan component C2.After the fluorescence quenching titration experiment,the contents of heavy metals in the complex state formed by<1 kDa DOC was the highest.Moreover,the complex stability constant of the two heavy metals complexed with<1 kDa DOC was the largest.The concentration of DOC-Pb(16.91-99.15μmol·L^(-1))was greater than DOC-Cu(12.42-95.99μmol·L^(-1)).However,the quenching degree and complex stability constant of Cu^(2+)and the two fluorescent components were stronger than that of Pb^(2+).The quenching effect of Cu^(2+)on component C1 was stronger than that of C2,indicating that Cu^(2+)was more inclined to complex with humus-like components.However,Pb^(2+)had no obvious tendency to complex with different components.The results provide guidance for the water quality maintenance and potential pollution control of landscape water in Beijing.

关 键 词：景观用水 溶解性有机碳 重金属 荧光特性 络合 

分 类 号：X522[环境科学与工程—环境工程]