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.
作者
关净文
侯乐
苏枞枞
沈建东
于兴娜
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)
出处
《中国环境科学》
EI
CAS
CSCD
北大核心
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)。
关键词
大气降水
化学组成
硫沉降
氮沉降
沈阳
atmospheric precipitation
chemical composition
sulfur deposition
nitrogen deposition
Shenyang
