济南市大气降水化学特征分析

Chemical Characteristics Analysis on Precipitation in Jinan

为了解济南市大气降水化学特征,于2015年1~12月在山东大学采集了降水样品,测定了p H值、电导率及水溶性无机离子、水溶性有机酸。结果表明,观测期间降水p H雨量加权均值为5.45,电导率均值为78.5μS/cm。降水中离子总浓度为1 189.07μeq/L,污染程度较为严重,其中SO_4^(2-)和NO_3^-是浓度较高的阴离子,NH4+和Ca2+是主要的阳离子。降水中SO_4^(2-)/NO_3^-为2.18,表明济南市大气污染向混合型转变趋势明显。济南市降水中有机酸浓度较低,甲酸和乙酸是主要的有机酸种类。

To better understand the chemical characteristics of atmospheric precipitation in Jinan,a comprehensive investigation was carried out in Shandong University from January to December2015, in which samples collected were analyzed for the parameters of pH, electrical conductivity（EC） and concentrations of inorganic ions and organic acids.The volume-weighted means of pH and EC were 5.45 and 78.5 μS/cm, respectively.The volume-weighted mean ionic concentration of the precipitation samples was 1 189.07 μeq/L, which implied the pollution was rather serious in Jinan.SO4^2- and NO3^- were the main anions in precipitation, while NH4^＋ and Ca^2 ＋were the main cations.The ratio of SO4^2- to NO3^- was 2.18, which showed that the type of air pollution in Jinan changed to be complex pollution.There were low concentration levels of organic acids in precipitation, while formate and acetate were the main organic acids.