屋面雨水干-湿沉降氮污染物迁移转化特性  

Nitrogen migration characteristics of dry and wet depositions in roofing rainwater

作　　者：李洁 高赞 王语翡 郑文昊 张琼华[1] LI Jie;GAO Zan;WANG Yu-fei;ZHENG Wen-hao;ZHANG Qiong-hua(School of Environmental and Municipal Engineering,Xi'an University of Architecture and Technology,Xi'an 710055,China)

机构地区：[1]西安建筑科技大学环境与市政工程学院,陕西西安710055

出　　处：《中国环境科学》2023年第7期3655-3663,共9页China Environmental Science

基　　金：国家自然科学基金资助项目(52270094)。

摘　　要：以氮污染物作为研究对象,研究了为期1a的15场降雨特征,采用相关性分析和非线性拟合等方法,探明了屋面雨水干、湿沉降过程氮污染物迁移变化规律.结果表明,各形态氮污染物在湿沉降与径流过程中的负荷削减规律显著相关,与降雨强度和COD变化相关性不强,尤其在降雨初期;针对氮污染物的初期冲刷效应分析发现,除总有机氮(TON)外均出现弱初期冲刷现象,冲刷强度从大到小在湿沉降中依次为:NO_(3)^(-)-N>NH_(4)^(+)-N>NO_(2)^(-)-N>TON;径流:NO_(3)^(-)-N>NO_(2)^(-)-N>NH_(4)^(+)-N>TON;同时发现干､湿沉降对屋面径流的平均TN贡献率分别为23.7%和76.3%,其中NH_(4)^(+)-N综合占比最高,达50%以上.掌握屋面雨水氮污染物干、湿沉降迁变特征,可为城市屋面径流污染控制措施的制订提供参考.In this study,correlation analysis and nonlinear fitting were adopted to explore the migration and transformation of nitrogen pollutants during dry and wet depositions of roof rainwater based on data collected from 15rainfall events for one year.The results show a significant correlation between the load reduction of all nitrogen pollutants in the process of wet deposition and runoff.However,no strong correlation was observed between rainfall intensity and COD,especially in the early rainfall period.An analysis of the first flush effect of nitrogen pollutants found that all,except TON,had a weak first flush phenomenon,and the wash-off intensity of the wet deposition varied as follows:NO_(3)^(-)-N>NH_(4)^(+)-N>NO_(2)^(-)-N>TON,whereas that in the runoff varied as NO_(3)^(-)-N>NO_(2)^(-)-N>NH_(4)^(+)-N>TON.In addition,the average TN contribution rates of dry and wet depositions to roof runoff were 23.7%and 76.3%,respectively,among which the NH_(4)^(+)-N comprehensive proportion was the highest,exceeding than 50%.Overall,the characteristics of dry and wet depositions and migration of nitrogen pollutants in roof rainwater were systematically elucidatred in this study,which can provide a reference for the formulation of urban roof runoff pollution control measures.

关 键 词：屋面径流 干沉降 湿沉降 初期冲刷 氮污染 

分 类 号：X501[环境科学与工程—环境工程]