上海宝山区酸雨特征分析

分析了连续七年(2004年-2010年)上海宝山区的降水的化学特征。从酸雨发生频率来看,2004年-2007年酸雨频率为:78.6%、75.9%、89.5%和94.6%,呈逐年加重的趋势,表明降水的酸性及酸化频率非常高,雨水酸化已非常严重。但从2008开始酸雨状况开始改善,酸雨频率开始降低,分别为:78.6%、41.1%和23.6%,同时其pH值开始高于全市平均水平;对降水中的各种阴阳离子进行数理统计分析:SO24-对降水的酸化起主要作用,但其作用在逐步减小,而NO3-和Cl-的作用呈上升的趋势;c(Cl-)/c(Na+)总体呈下降趋势,说明化工、有色金属冶金等工业生产废气中Cl2和HCl等污染物作用减少;因子分析反映了降水的来源成因机制,其结果与相关性分析一致。

Chemical Characteristics Analysis on Acid Rain in Baoshan District

Chemical components characteristics of precipitation in seven consecutive years（2004-2010） in Baoshan district are investigated.The frequency of acid rain from 2004 to 2007 is 78.6%,75.9%,89.5% and 94.6%,respectively.The yearly increasing trend indicates that the precipitation acidity is very serious.However,the situation began to improve form 2008 and acid rain frequency began to decrease from 2008 to 2010 with frequency of 78.6%,41.1% and 23.6%,respectively.The pH value is higher than the average value of the whole city.Volume-weighted mean concentrations of various ions in precipitation are statistical analyzed.The contribution of SO2-4 to rainwater chemical components reduced gradually,while that of NO-3 and Cl-is increased.C（Cl-）/C（Na＋）is in an overall downward trend,indicating that the pollutants such as Cl2 and HCl play lesser role in chemical industry,nonferrous metals metallurgy and other industrial emissions.Factor analysis reflects that the formation mechanism of the precipitation,the result of which is consistent with correlation analysis.