淮南市降水化学组成特征与来源分析

Chemical Composition and Source Assessment of Precipitation in Huainan

2013—2014年,逐次采集淮南城市大气降水样品,对其离子化学组分进行分析测试,并利用酸度分析、中和因子和富集系数等方法对其酸碱物质平衡和离子来源进行了分析。化学组分分析结果表明,淮南城市降水pH为6.237.03,雨量加权平均值为6.68,整体上降水没有呈现酸化,大部分酸性物质能被碱性物质中和。主要阴离子为SO42-、NO3-,雨量加权平均值分别为147.02、62.16μeq/L,两者分别占阴离子总浓度的60.3%、25.3%;主要阳离子为Ca2＋ 、NH4＋,雨量加权平均值分别为126.42、96.43μeq/L,分别占阳离子总浓度的44.9%、34.3%。利用富集系数法计算结果表明,SO42-、NO3-主要来源于人为活动排放,Cl-主要为海洋输入,而Ca2＋ 、Mg2＋、K＋则主要来自陆源输入和人为活动。

During the period from 2013 to 2014,precipitation in Huainan City was sampled to characterize its chemical composition. Based the obtained data,its acid-base balance was analyzed by using acidity analysis and neutralizing factor methods,and then ions source was assessed by employing the enrichment coefficients（ EF）. The results showed that the p H of samples varied from 6. 23-7. 03,with the volume-weighted average of 6. 68,the acidification of local rainwater was not very serious,and most of acidic components in precipitation can be neutralized by alkaline materials. The volume-weighted average concentrations of SO42- and NO3- were 147. 02,62. 16 μeq/L,with the percent contribution to anions of 60. 3%,25. 3%,respectively. Ca2＋ and NH4＋ were the major cations and the volume-weighted average concentrations were 126. 42,96. 43 μeq/L,with the percent contribution to cations of 44. 9%,34. 3%,respectively. Results of EF indicated that： SO42- and NO3-primarily come from the emission by human activities,Cl-comes from the marine transport,and Ca2＋ ,Mg2＋ and K＋ come from terrestrial contribution and human activities.