湖南省大气湿沉降化学研究

以湖南省1999～2001年的酸雨监测数据为基础,运用统计学和线性回归分析方法研究了位于中国中南部的重酸雨区湖南省的大气降水的酸度和化学组成的分布特征以及季节变化规律。结果表明,大气降水以SO_4~(2-)为主,占总离子量的31％,大气降水阴阳离子基本平衡。降水年平均pH值为4.86,以春季酸度最大,降水离子总量以冬季最大。研究结果同时表明,降水酸度是主要酸性离子和主要碱性离子共同作用的结果,而且(H~+]+NH_4~+])/(SO_4~(2-)]+NO_3~-])比值的变化能较好的反映降水过程中强酸离子的中和现象。

Study on the atmospheric chemistry of wet deposition in Hunan province

By means of statistics and regression analysis, the spatial and temporal distribution of acidity and chemical composition and seasonal variation regularity are studied based on the acid rain monitoring data ranging from 1999 to 2001 in Hunan province, a severe acid rain area located in the Central-South China- The results show that the dominated ion is SO_4~(2-) , accounting for 31% of the amount of the total precipitation. There is a general balance between the cation and the anion of precipitation. The annual averaged pH value is 4. 86, with the largest amount of ion in winter. The research also shows that the acidity of precipitation is the result of the interaction between the major acidic ions and the major alkaline ones, moreover, the variance of the ratio of (H~+]+NH_4~+ ])/( SO_4~(2-)] + NO_3~-]) can efficiently reflects the facts that the strong acidic ions neutralized by the alkaline substances during precipitating.