沈阳市大气降水污染与沉降特征的城郊差异  

Urban and suburban differences in precipitation pollution and deposition characterization in Shenyang

作　　者：关净文 侯乐 苏枞枞 沈建东 于兴娜[1] GUAN Jing-wen;HOU Le;SU Cong-cong;SHEN Jian-dong;YU Xing-na(Key Laboratory for Aerosol-Cloud-Precipitation of China Meteorological Administration,Nanjing University of Information Science and Technology,Nanjing 210044,China;Shenyang Ecological and Environmental Monitoring Center of Liaoning Province,Shenyang 110000,China;Hangzhou Ecological Environment Monitoring Center of Zhejiang Province,Hangzhou 310012,China)

机构地区：[1]南京信息工程大学,中国气象局气溶胶与云降水重点开放实验室,江苏南京210044 [2]辽宁省沈阳生态环境监测中心,辽宁沈阳110000 [3]浙江省杭州生态环境监测中心,浙江杭州310012

出　　处：《中国环境科学》2024年第6期3052-3059,共8页China Environmental Science

基　　金：国家自然科学基金资助项目(41775154);安徽省重点研究与开发计划项目(2022h11020008);江苏省“六大人才高峰”项目(JNHB-057)。

摘　　要：为了解沈阳地区大气降水污染与沉降特征的城郊差异,对2018~2022年沈阳市铁西区站点(城市)和苏家屯站点(郊区)降水样品的电导率、pH值和各种水溶性离子浓度及其沉降量进行了研究.结果表明,观测期间两站点平均pH值分别为7.12(6.09~8.36)和7.11(5.88~8.19),均呈碱性,无酸性降水.城郊站点的降水电导率和总水溶性离子平均浓度差异不大,2018~2022年期间整体呈现下降趋势.沈阳两站点的相对酸度(FA)均值为0.0004,(Ca^(2+)+NH_(4)^(+))/(SO_(4)^(2-)+NO_(3)^(-))均值分别达到了1.57和1.61,表明碱性离子的中和能力较强.大气降水中NO_(3)^(-)/SO_(4)^(2-)的比值介于0.41~0.58,SO_(4)^(2-)-S湿沉降量分别是NO_(3)^(-)-N和NH_(4)^(+)-N沉降量的1.14倍~2.20倍,表明沈阳大气降水主要以硫沉降为主.城市站的无机氮沉降量总体上高于郊区站,其中NH_(4)^(+)-N平均沉降量分别是NO_(3)^(-)-N的1.74和1.78倍,说明沈阳市大气降水中的无机氮以还原态氮占主导,这主要与汽车尾气、城市绿地养护、人体排泄物以及郊区频繁的农业活动相关.In order to understand the differences of precipitation pollution and deposition characteristic in Shenyang,the electrical conductivity,pH value,and concentration and deposition of water-soluble ion in precipitation were studied at Tiexi(urban)and Sujiatun(suburb)stations in Shenyang during 2018~2022.The results showed that the average pH values of two stations were 7.12(6.09~8.36)and 7.11(5.88~8.19),respectively,which indicated that precipitation was alkaline.The precipitation conductivity and the average concentration of total water-soluble ions at two sites were similar and showed a downward trend from 2018 to 2022.The mean relative acidity(FA)of the two sites in Shenyang was 0.0004,and the mean values of(Ca^(2+)+NH_(4)^(+))/(SO_(4)^(2-)+NO_(3)^(-))were 1.57 and 1.61,respectively,indicating strong neutralization ability of alkaline ions.The ratio of NO_(3)^(-)/SO_(4)^(2-)in precipitation was between 0.41 and 0.58.The wet deposition of SO_(4)^(2-)-S was 1.14 and 2.20 times that of NO_(3)^(-)-N and NH_(4)^(+)-N,respectively,indicating that the precipitation in Shenyang was mainly dominated by sulfur deposition.The inorganic nitrogen deposition of urban station was generally higher than that of suburban station.The average deposition of NH_(4)^(+)-N was 1.74 and 1.78 times that of NO_(3)^(-)-N,respectively,implying that inorganic nitrogen in precipitation in Shenyang was dominated by reduced nitrogen.This was mainly related to automobile exhaust,urban green land maintenance,human excrement and frequent agricultural activities in the suburbs.

关 键 词：大气降水 化学组成 硫沉降 氮沉降 沈阳 

分 类 号：X517[环境科学与工程—环境工程]