摘要
为了解陇南市大气降水的化学组成特征和来源,收集陇南市2018-2024年间651个降水样品的监测数据,分析了降水量、pH值、电导率和9种可溶性阴阳离子的化学组成特征。研究结果表明,pH值范围为6.60~8.90,7年均值为7.58,降水类型为弱碱性降水,电导率变化范围为0.97~24.1μS·m^(-1),7年均值为3.62μS·m^(-1),说明陇南市大气环境质量较为清洁,但其可溶性离子含量水平已受到城市发展的影响;2018-2024年陇南市大气降水中主要阳离子为Ca^(2+),占阳离子总量的65.1%,SO_(4)^(2-)为主要阴离子,占阴离子总量的59.9%。[SO_(4)^(2-)]/[NO_(3)^(-)]比值7年均值为4.1,酸雨类型整体上为硫酸型;陇南市大气降水中可溶性离子主要以硫酸盐和硝酸盐的形式存在,无机阴离子SO_(4)^(2-)与NO_(3)^(-)主要来源是燃煤源、汽车尾气、砖厂废气排放等,阳离子Mg^(2+)和Ca^(2+)来源于扬尘和建筑粉尘等陆原形颗粒物,其余离子之间也具有显著相关性,但这些离子可能受到多种来源和因素的影响。
In order to understand the chemical composition characteristics and sources of atmospheric precipitation in Longnan City,the monitoring data of 651 precipitation samples from 2018 to 2024 were collected,and precipitation,pH,electrical conductivity and 9 inorganic ions of the precipitation were analyzed.The results showed that pH value ranges from 6.60 to 8.90,with a 7 year mean value of 7.58,the precipitation type is weakly alkaline.The electrical conductivity ranged from 0.97 to 24.1μS·m^(-1),with a 7 year mean value of 3.62μS·m^(-1),indicating that the atmospheric environment quality of Longnan City was relatively clean,but its soluble ion content was affected by urban development.In the atmospheric precipitation of Longnan City from 2018 to 2024,the main cation was Ca^(2+),accounting for 65.1%of the total cation,and SO_(4)^(2-) was the main anion,accounting for 59.9% of the total anion.The average value of[SO_(4)^(2-)]/[NO_(3)^(-)]ratio in 7 years was 4.1,and the acid rain type was sulfuric acid type on the whole.Soluble ions in the atmospheric precipitation of Longnan City mainly existed in the form of sulfate and nitrate,inorganic anions SO_(4)^(2-) and NO_(3)^(-) were mainly derived from coal sources,automobile exhaust,and exhaust emissions from brick factories,etc.Cations Mg^(2+)and Ca^(2+)were derived from continental particles such as blowing dust and building dust.There were also significant correlations between the remaining ions,but these ions can be influenced by a variety of sources and factors.
作者
李芳霞
刘明延
张娇娇
LI Fangxia;LIU Mingyan;ZHANG Jiaojiao(Longnan Environment Monitoring Center,Gansu Longnan 746000,China)
出处
《广州化工》
2026年第5期131-134,共4页
GuangZhou Chemical Industry
基金
陇南市科技计划项目资助(2024SZ58,2024SZ60)。
关键词
大气降水
化学特征
来源分析
陇南市
atmospheric precipitation
chemical properties
source analysis
longnan city
