天津降水季节特征及不同气团来向离子来源分析  

Seasonal characteristics of precipitation in Tianjin and sources of ion from different air masses

作　　者：杨璟爱 韩少强 杨健安 王记鲁 刘金冠 田雨 张亚尼 薛鹏飞 王艳丽 赵志强 陈晨 崔连喜 杨华 张静 YANG Jing-ai;HAN Shao-qiang;YANG Jian-an;WANG Ji-lu;LIU Jin-guan;TIAN Yu;ZHANG Ya-ni;XUE Peng-fei;WANG Yan-li;ZHAO Zhiqiang;CHEN Chen;CUI Lian-xi;YANG Hua;ZHANG Jing(Tianjin Eco-Environmental Monitoring Center,Tianjin 300191,China;Tianjin Huanjian Environmental Testing Co.,Ltd.,Tianjin 300300,China;Tianjin Tianbinruicheng Environmental Technology and Engineering Co.,Ltd.,Tianjin 300190,China)

机构地区：[1]天津市生态环境监测中心,天津300191 [2]天津市环鉴环境检测有限公司,天津300300 [3]天津天滨瑞成环境技术工程有限公司,天津300190

出　　处：《中国环境科学》2023年第4期1844-1856,共13页China Environmental Science

基　　金：生态环境部标准编制项目[2018-4]。

摘　　要：基于天津2019年3月~2022年2月的大气降水样品,分析降水季节性变化及无机离子和有机酸来源,降水pH值均值为6.68,电导率均值为46.8μS/cm,总离子浓度均值为726μeq/L,降水离子整体呈现“冬高夏低”的季节特征,SO_(4)^(2-)和NO_(3)^(-)对总自由酸度(TFA)的贡献率为89.6%,是主要致酸离子.基于HYSPLIT模型得出降水主要受5个来向气团影响,春冬季以离子浓度较高的北部气团和西北部气团来向为主,占比60.0%~62.5%,夏秋季离子浓度较低的南部气团、东部气团和东南部气团占比较大,达到60.0%~97.8%.富集因子分析表明Ca^(2+)、Mg^(2+)和K^(+)主要来源于土壤;Cl^(-)的主要来源为海洋;Na^(+)的来源包括土壤;SO_(4)^(2-)和NO_(3)^(-)主要来自人为源.根据有机酸来源判定,植物生长和土壤释放等直接来源对天津有机酸浓度贡献较大,不饱和烃类的大气光化学反应等间接来源贡献较小.正矩阵因子分析(PMF)源解析表明,天津大气降水离子来源包括生物质燃烧源、垃圾焚烧源、二次无机源、生物排放和二次有机源、海源及工业源、陆源及扬尘源.Based on the atmospheric precipitation samples from March 2019 to February 2022 in Tianjin,the seasonal changes of precipitation and the sources of inorganic ions and organic acids were analyzed.The mean pH value of precipitation was 6.68,and the mean conductivity was 46.8μS/cm,and the mean value of total ion concentration was 726μeq/L.The precipitation ions generally showed the seasonal character of"high in winter and low in summer".SO_(4)^(2-)and NO_(3)^(-)accounted for 89.6%of total free acidity(TFA)and were the main acid causing ions.According to the HYSPLIT model,precipitation was mainly caused by five incoming air masses.In spring and winter,the main source was the high-ion-concentration air mass from northern and northwest areas.These two accounted for the largest proportion,which reached 60.0%~62.5%.In summer and autumn,the precipitation was mainly caused by the low-ion-concentration air mass from southern,eastern and southeast areas,the sum of which accounted for 60.0%~97.8%.Enrichment factor analysis showed that Ca^(2+),Mg^(2+)and K^(+)mainly came from soil,Cl^(-)mainly came from the ocean,Na^(+)came from sources included soil,while SO_(4)^(2-)and NO_(3)^(-)mainly came from anthropogenic sources.In addition,according to the sources of organic acids,direct sources,such as plant growth and soil release,had a greater contribution to the organic acid concentration in Tianjin,while indirect sources,such as atmospheric photochemical reaction of unsaturated hydrocarbons,had a smaller contribution.Positive matrix factorization(PMF)source analysis showed that the ion sources of atmospheric precipitation in Tianjin included biomass combustion,garbage incineration,secondary inorganic sources,biological emissions and secondary organic sources,sea and industrial sources,as well as land and fugitive dust.

关 键 词：降水 无机离子 有机酸 后向轨迹 正交矩阵因子模型(PMF) 

分 类 号：X131[环境科学与工程—环境科学]