北京市春夏季降水及其对大气环境的影响研究  

Studies on precipitation and its effects on atmospheric environment in Beijing in spring and summer

作　　者：韩力慧[1] 张海亮[1] 张鹏[1] 向欣[1] 程水源[1] 魏巍[1] HAN Li-hui;ZHANG Hai-liang;ZHANG Peng;XIANG Xin;CHENG Shui-yuan;WEI Wei(Key Laboratory of Beijing on Regional Air Pollution Control, College of Environmental and Energy Engineering, Beijing University of Technology, Beijing 100124, China)

机构地区：[1]北京工业大学,环境与能源工程学院,区域大气复合污染防治北京市重点实验室,北京100124

出　　处：《中国环境科学》2017年第6期2047-2054,共8页China Environmental Science

基　　金：国家环保公益性行业科研专项(201409003);国家留学基金委资助项目(201406545022);北京市教委项目(PXM2016_014204_001029_00205967_FCG)

摘　　要：通过采集北京市2015年春夏季大气降水和大气颗粒物样品,分析研究了大气降水的理化特性,时空变化特征,来源以及对大气颗粒物的影响.结果表明,北京市春夏季降水量主要集中于夏季,降水p H值在南城和北城分别为6.26和6.08,呈偏中性,均表现为春季大于夏季.降水中地壳元素Al和Fe含量较高,Ti、V和Ce含量较低.污染元素Ca和S含量最高,Na和Mg含量较高,Zn、Mn、Cu、Sr、Pb和Ni含量较低,其中Na、Mg、Sr和Ni呈现轻度富集,Ca、Mn和Pb呈现中度富集,Cu、Zn和S呈现严重富集.此外,降水中元素浓度具有显著的季节变化,二次污染元素S表现为夏季高于春季,而其它元素均表现为春季高于夏季;同时也具有较大的空间变化,除Pb元素外,均为南城高于北城.降水中化学组分主要来源于地面扬尘、建筑活动、燃煤、机动车尾气和工业排放.大气降水对大气颗粒物的去除率受降水强度以及前一天空气质量的影响较大,且对细颗粒物PM_(2.5)中污染元素Cu、Zn、Mn和Na清除效果显著,对粗颗粒物PM_(10)中地壳元素Al和建筑尘相关元素Mg和Ca去除效果明显.A campaign of sampling atmospheric precipitation and particulate matter samples in Beijing in both spring andsummer of2015was carried out to investigate the physical and chemical characteristics,temporal and spatial variationsand sources of precipitation and its impacts on atmospheric particulate matter.A large amount of rainfall in spring andsummer mostly occurred in summer.The volume-weighted mean(VWM)pH value of rainwater in the south of Beijing inspring and summer was6.26,a little higher than that of6.08in the north,indicating that the rainwater in Beijing waslargely non-acidic.At the same time,the VWM pH in spring was higher than that in summer in Beijing.Theconcentrations of major crustal elements in rainfall such as Al and Fe,were relatively high,while Ti,V and Ce wererelatively low.The concentrations of major pollution elements in rainwater such as Ca and S,were much high,Na and Mgwere relatively high,but Zn,Mn,Cu,Sr,Pb and Ni were relatively low,of which Na,Mg,Sr and Ni were lightly enrichedin rainwater,Ca,Mn and Pb were enriched,and Cu,Zn and S were heavily enriched in rainwater.Furthermore,theconcentrations of major elements in rainwater displayed the significant seasonal variations,of which the concentration ofsecondary pollution element S in summer was higher than that in spring,while the concentrations of the others in springwere higher than those in summer.The important spatial variations of major elements in rainwater have been shown,ofwhich the concentrations of major elements in the south of Beijing,except for Pb,were higher than those in the north.Thechemical compositions of precipitation were mainly from crustal dust,construction activities,coal combustion,vehicleemission and industrial emission.The scavenging effect of precipitation to aerosol particles and their components from theair was generally impacted by the rainfall intensity and the concentrations of pollutants before precipitation events.The precipitation could effectively scavenge pollution elements in fine particle PM2.5,such as C

关 键 词：大气降水 大气颗粒物 化学组分 来源解析 去除率 

分 类 号：X517[环境科学与工程—环境工程]