基于3DEMMs-PARAFAC技术的运河桐乡水源地夏季低溶解氧成因研究  

Study on the cause of low dissolved oxygen in summer in Tongxiang water source of Canal based on 3DEMMs-PARAFAC technology

作　　者：丁淼 金梦 兰亚琼 金晓燕 赵远 刘锐 DING Miao;JIN Meng;LAN Yaqiong;JIN Xiaoyan;ZHAO Yuan;LIU Rui(School of Environmental and Safety Engineering,Changzhou University,Changzhou,213164,China;Zhejiang Provincial Key Laboratory of Water Science and Technology,Department of Environment in Yangtze Delta Region Institute of Tsinghua University of Zhejiang,Jiaxing,314006,China;Tongxiang Eco-Environmental Monitoring Station of Jiaxing,Jiaxing,314500,China)

机构地区：[1]常州大学环境与安全工程学院,常州213164 [2]浙江省水质科学与技术重点实验室,浙江清华长三角研究院生态环境研究所,嘉兴314006 [3]嘉兴市桐乡生态环境监测站,嘉兴314500

出　　处：《环境化学》2023年第6期1933-1944,共12页Environmental Chemistry

基　　金：浙江省科技创新领军人才项目(2020R52039);嘉兴市“创新嘉兴优才支持计划”项目;江苏省研究生科研与实践创新计划项目(SJCX21_1195)资助.

摘　　要：运河桐乡水源地处长江流域太湖水系,是桐乡市70多万人的集中饮用水水源,近年来连续数年夏季溶解氧(DO)偏低,影响水源地水质稳定达标.基于三维荧光光谱(3DEEMs)结合平行因子分析(PARAFAC)技术,以及常规水质分析和氮形态解析,研究了上游来水、桐乡自身污染以及运河底泥释放对水源地DO的影响,解析了夏季低DO成因.结果表明,桐乡入境水具有生活污水荧光特征峰,夏季DO浓度低、氨氮浓度高,是造成运河桐乡水源地DO不能稳定达标的首要原因,桐乡入境水和桐乡水源地取水口DO显著正相关(R^(2)=0.76,P<0.01).其次,运河桐乡段水体中DOM主要由3个荧光组分组成,其中C1(230/275,307)和C2(235/295,338)为类蛋白质荧光组分,C3(255/330,297/422)为类腐殖质荧光组分;水源地保护区内类蛋白质物质荧光强度大幅增强,在总荧光强度中占比67.6%—95.9%,显示村镇生活污水排放对水源地水质有所影响.此外,运河干流通航引起底泥悬浮、水体浊度上升从而影响光合作用,以及支流底泥在缺氧条件下的氮磷释放进一步加剧了水源地DO消耗.在此基础上针对性提出对策建议,为运河桐乡水源地水质提升和平原河网地区低氧水体治理提供理论依据.Located in the Taihu River system of the Yangtze River Basin,Tongxiang Canal is used as the centralized drinking water source for more than 700,000 people.In recent years,the low summer dissolved oxygen(DO)has affected the water quality of the water source to reach the standard.Based on the three dimensional fluorescence spectrum(3DEEMs)combined with the parallel factor analysis(PARAFAC)technology,as well as the conventional water quality analysis and nitrogen form analysis,factors that influence DO were studied,including upstream inflow,Tongxiang’s municipal pollution and the sediment release.The results showed that the incoming water in Tongxiang had the fluorescent characteristic peak of domestic sewage,and the low concentration of DO and high concentration of ammonia nitrogen are the primary contributor to the low DO concentration in the Tongxiang canal water source in summers.A significant positive correlation of the daily average DO concentration was found between the upstream inflow and the intake of water source(R^(2)=0.76,P<0.01).Secondly,DOM in Tongxiang section of Canal is mainly composed of three fluorescent components.C1(230/275,307)and C2(235/295,338)are protein-like fluorescent components,and C3(255/330,297/422)are humus-like fluorescent components;the fluorescence intensity of protein-like substances increased significantly in the water source protection area,accounting for 67.6%—95.9%of the total fluorescence intensity,indicating that rural domestic sewage discharge had an impact on the water quality of the water source.In addition,inland shipping negatively affects photosynthesis by causing sediment suspension and turbidity of the river,and nitrogen and phosphorus released from tributary sediment under oxygen-poor conditions further aggravate DO consumption in the waterbody.On this basis,countermeasures and suggestions were put forward for forming a framework to improve the quality of the Tongxiang canal water source and other low oxygen water body in plain river network areas.

关 键 词：水源地 溶解氧 三维荧光光谱 平行因子分析 成因分析 控制策略 

分 类 号：X52[环境科学与工程—环境工程]