摘要
溶解性有机质(DOM)是城市雨水径流中有机污染物的重要组分,可与重金属、多环芳烃等污染物络合,对城市受纳水体造成危害。为探究雨水径流DOM的特性及污染来源,以西安市主城区为例,采集3个功能区(文教区、交通区和商业区)不同下垫面的径流样品,利用紫外-可见吸收光谱、三维荧光光谱结合平行因子分析和红外光谱技术,分析DOM组分类型及变化特征,并采用主成分-多元线性回归模型(PCA-MLR)进行污染源解析。结果表明:①除TP以外,3个功能区雨水径流的常规水质指标均未达到GB 3838−2002《地表水环境质量标准》中Ⅳ类水质标准,路面径流DOM含量均高于屋面径流,其中,交通区DOM污染最为严重(42.17~58.80 mg/L),其次是商业区(27.37~54.72 mg/L)。②雨水径流共解析出3类6种荧光组分,路面径流DOM组分较屋面径流更为复杂,前者包括4种腐殖质、1种富里酸和1种类蛋白,后者包括3种腐殖质和1种富里酸,且随着降雨历时的延长,DOM各组分含量呈现下降趋势。③各功能区路面径流DOM所含的主要官能团种类相同,包括−OH、−COOH和苯环等官能团,以及C=C、C=O等不饱和键,其不随降雨历时的变化而改变。④源解析发现,屋面径流DOM污染源包括大气沉降污染(贡献率为44.2%)、屋面材料析出物与交通污染(贡献率为55.8%);路面径流DOM污染源包括交通活动污染(贡献率为39.8%)、大气沉降与土壤侵蚀污染(贡献率为22.4%)、生活污染(贡献率为37.8%)。研究显示,西安市各功能区不同下垫面DOM存在明显的结构性及来源差异,研究成果可为从源头控制城市水环境污染问题提供科学依据。
Dissolved organic matter(DOM)is a significant component of organic pollutants in urban rainwater runoff.It can form complexes with heavy metals and polycyclic aromatic hydrocarbons,affecting the health of the receiving water bodies.In order to explore the characteristics and sources of DOM in rainwater runoff,taking the main urban area of Xi′an as an example,samples were collected from different underlying surfaces in the three functional areas(cultural and educational,traffic and commercial districts).UV-Visible(Ultraviolet-Visible spectroscopy)absorption spectroscopy,3D-EEMs(three-dimensional fluorescence spectroscopy)combined with PARAFAC(parallel factor),and infrared spectroscopy techniques were used to analyze component types and variations of DOM.Pollution source apportionment was carried out using PCA-MLR(principal component analysis-multiple linear regression)modeling.The results showed that:(1)Except for TP,the quality in rainwater runoff in all three functional areas did not meet the ClassⅣsurface water standards of Environmental Quality Standards for Surface Water(GB 3838-2002).The DOM content in the road runoff is consistently higher than that in roof runoff,in which DOM pollution was the worst in transportation area(42.17-58.80 mg/L),followed by the commercial areas(27.37-54.72 mg/L).There are distinct structural differences in DOM among various functional areas with different underlying surfaces.(2)Rainwater runoff was collectively classified into three categories containing six fluorescent components.The DOM components in road runoff are more complex than that in roof runoff.The DOM components in road runoff were more complex than those in roof runoff.The contained four kinds of humic substances,one kind of fulvic acid,and one kind of protein,while the latter contained three types of humic substances and one type of fulvic acid.Moreover,with the extension of rainfall duration,the content of each DOM component shows a decreasing trend.(3)The main functional groups of DOM in road runoff of all fu
作者
侯思远
胡德秀
马龙
刘子晨
马勃
杨霄
胡长玲
HOU Siyuan;HU Dexiu;MA Long;LIU Zichen;MA Bo;YANG Xiao;HU Changling(State Key Laboratory of Eco-Hydraulics in Northwest Arid Region,Xi′an University of Technology,Xi′an 710048,China;Power Construction Corporation of China Northwest Survey and Design Institute Co.,Ltd.,Xi′an 710065,China;Urban and Rural Planning Mapping Service Center,Weinan 714000,China)
出处
《环境科学研究》
CAS
CSCD
北大核心
2024年第6期1292-1302,共11页
Research of Environmental Sciences
基金
省部共建西北旱区生态水利国家重点实验室基金资助项目(No.2016ZZKT-8)
水利水电学院国家级实验教学示范中心项目(No.WRHE1709)。
关键词
雨水径流
溶解性有机质(DOM)
荧光特征
源解析
西安市
rainwater runoff
dissolved organic matter(DOM)
fluorescence characteristics
source apportionment
Xi′an
