中国科学院机构知识库网格
Chinese Academy of Sciences Institutional Repositories Grid
典型城市下垫面对集水区降雨径流污染的影响研究——以北京市为例

文献类型:学位论文

作者武俊良
学位类别博士
答辩日期2015
授予单位中国科学院研究生院
授予地点北京
导师刘刚才
关键词城市面源污染 下垫面径流 集水区径流 污染特征
其他题名Research on the Effects of Typical Urban Underlying Surface on Catchment Runoff Pollution——Take Beijing for Example
学位专业土壤学
中文摘要城市化是当前人类对全球社会经济生态环境影响最严重的因素之一。快速的城市化过程一方面促进了社会经济的发展,与此同时,也给城市以及周边区域带来了一系列的生态环境问题。城市及其周围水环境污染问题是城市化所带来的环境问题之一,特别是城市点源污染控制的不断完善,如何认识并有效控制城市降雨径流污染成为一个迫切需要解决的重要课题。本研究以集水区为研究单元,研究了大气降雨(湿沉降,干沉降和混合沉降)和典型城市下垫面(屋面、道路和草地)径流污染特征、污染物来源和污染物负荷,揭示降雨径流中污染形成及其排放规律,探讨不同下垫面对城市面源污染的影响特征及机制,旨在为我国城市水环境管理决策提供科学依据。研究获得以下主要结果: (1)北京市降雨水质差,总体上为劣V类水质,主要污染指标为N和COD,且不同场次降雨污染物浓度变异程度大。雨水中含氮污染物主要来源于汽车尾气、燃煤等,并主要为硝态氮和铵态氮,是城市降雨径流中氮的主要来源。天然降雨污染物的排放负荷存在月初始冲刷效应,即大约50%的降雨污染物排放主要集中在7月中旬之前。城市降雨水质具有空间异质性,郊区好于市区。降雨能有效清除大气中PM2.5,大雨和暴雨能去除大气中的SO2和NOX。 (2)屋面降雨径流污染严重,水质为劣V类水质,主要污染指标为SS、N、COD和NH4-N。大气沉降是屋面径流中污染物的主要来源,同时水泥屋面材料和沥青屋面材料分别是其径流中氮和难降解有机物、重金属(各约占60%)的重要来源。屋面径流中46%颗粒物主要是10μm~50μm粒径范围内的颗粒物,氮主要是溶解态(粒径小于0.45μm)排放,而磷和COD是以颗粒态(10μm~50μm颗粒物)排放。屋面径流中污染物的排放存在初始冲刷现象,污染物形态和来源影响其冲刷的程度。 (3)城市道路径流主要污染指标为SS、COD、N和NH4-N,水质为劣V类水质。道路径流中颗粒物,磷和部分重金属主要来源于非大气沉降源。90%以上颗粒物主要是粒径为0.45μm~50μm颗粒物为主,70%~80%的磷是以颗粒态的形式排放,85%氮污染物主要是以溶解态的形式排放。除了小颗粒物比表面大的原因外,颗粒物表面大量小腔和其组分也是颗粒物与其他污染物转移关系密切的重要原因。 (4)草地径流主要污染物为SS、COD、N和P,其中颗粒物污染最为严重,主要以0.45μm~50μm小粒径的颗粒物为主(占50%),平均浓度可达1074.7 mg·L-1。草地下垫面是草地径流中颗粒物和磷的主要来源,分别占95%和80%。草地径流颗粒物转运污染物主要是依据吸附和组分机制为主。径流中氮是以溶解态形式排放,磷和COD是以颗粒态形式排放。除颗粒物外,草地能消减降雨径流污染物的排放,净化径流水质。 (5)集水区径流水质受SS、 P、COD、N和溶解态重金属污染物的影响,污染严重。集水区径流中大约70%颗粒物来源于道路和草地径流,80%氮来源于大气沉降,90%磷源于大气沉降、草地和道路径流,沥青屋面和集水区通风设施是集水区径流中重金属主要来源。76%颗粒物是以粒径范围在0.45μm~50μm的颗粒物,78.6%的氮是以溶解态排放(粒径小于0.45μm),且39%氮是硝态氮。75%磷是以颗粒态排放(主要结合10μm~50μm,占66%)。集水区径流中污染物的浓度存在混合平均效应。集水区污染物的排放存在初始冲刷特征,最近距离下垫面、污染物形态和来源影响其排放特征。 (6)城市降雨径流污染是以降雨为主要影响因素,下垫面及其构成比例是影响集水区径流中污染排放的重要因素,污染物的形态和来源是径流中污染排放的决定性因素。通过调节集水区内下垫面配置比例能有效地降低区域径流中污染物的排放,缓解降雨径流对环境的影响。区域透水面最佳比例为60%~30%,不同下垫面的配置存在减少降雨径流污染的最佳比例范围。
英文摘要Urbanization is one of the most serious factors that affect the global socio-economic environment. The rapid urbanization has promoted the development of social economy, but also has brought about a series of ecological environment problems to the city as well as the surrounding areas. Water environment pollution is one of environmental problem caused by urbanization, especially when point sources pollutants are treated effectively, non-point pollution, which that generally related with stormwater runoff, have become a difficult challenge for clear water. This study investigates pollution features, pollution sources and loading of atmospheric rainfall (wet deposition, dry deposition, and mixed settlement) and runoff from typical urban underlying surfaces (roofs, roads, and grass), aim to reveal the formation course and wash-off law of pollutants and to discuss the influence and mechanism of underlying surface on the urban non-point pollution in the range of the catchment, which can provide a theoretic basis for urban water environment management. The main research results are as follows: (1) The water quality of rainwater was mostly polluted, pollution was serious and the variation degree of pollution was apparent. N and COD are the main pollutants of rainwater, and the composite water quality of rainwater was in V class of surface water. Atmospheric wet deposition nitrogen (N) mainly comes from automobile exhaust, coal-combustion and emission of regional agricultural source. Atmospheric deposition is the main sources of nitrate in urban runoff. Nitrate nitrogen (NO3--N) and ammonium nitrogen (NH4-N) are major form of nitrogen in the rainfall. Month first flush exits in the rainfall pollution emission loads, about 50% of pollution emission occurred before mid-July. City rainfall water was spatial heterogeneity, and its quality in suburb was better than that in urban area. Precipitation can effectively remove PM2.5 and heavy rain and storm can be removed SO2 and NOX in atmosphere. (2) The water quality of roof runoff is pollution serious and the main pollutants of roof runoff are SS, N, COD and NH4-N. Atmospheric deposition was the main sources of nitrate in Beijing urban roof runoff. Concrete material is another source of nitrate in the concrete roof runoff, and asphalt material is sources of COD and dissolves heavy metal (HM) in the roof runoff (60%). 46% of SS is particle sizes 10μm~50μm in roof runoff, and N is transported mainly in a dissolved form (<0.45μm) and P and COD in particle association (attached to particle sizes of 10μm~50μm) in urban roof runoff. The pollutants wash-off is characterized of the first flush (FF) phenomenon in the roof runoff, and the form and source of pollution affect the pollutants emission characteristic. (3) SS, COD, N and NH4-N were the main pollutants in the urban road runoff, and the water quality was in V class of surface water. The main sources of SS, P and HM in the road runoff are non-atmosphere deposition. The small particulates in the range of 0.45μm~50μm consisted of 90% SS in the road runoff. P was mainly attached to particle sizes of 10μm~50μm in the road runoffs (70%~80%), while 85% N was mainly in a dissolved phase state in road runoff. Particles are involved in the transport of pollutant in the runoff. Except the higher specific surface area of the smallest particle to absorb more contamination, small hole on the surface of particles and its phosphate mineral components are also important reasons. (4)Lawn runoff of major pollutions being SS, COD, N and P,in which SS is most serious, mainly with smaller particle sizes of particulate matter (0.45μm~50μm,50%),the SMC SS was 1074.68 mg·L-1. The contributions of SS and P from the lawn surface to that in lawn runoff are 95% and 80%, respectively. And lawn surface sediments are important source of SS and P. The mechanism of SS transportation of P is absorption and composition of the SS in the lawn runoff. N was transported main
语种中文
公开日期2016-04-26
源URL[http://ir.imde.ac.cn/handle/131551/15054]  
专题成都山地灾害与环境研究所_山地灾害与地表过程重点实验室
作者单位中国科学院成都山地灾害与环境研究所
推荐引用方式
GB/T 7714
武俊良. 典型城市下垫面对集水区降雨径流污染的影响研究——以北京市为例[D]. 北京. 中国科学院研究生院. 2015.

入库方式: OAI收割

来源:成都山地灾害与环境研究所

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