中文摘要：

对贵阳地区2008年10月30日～11月7日的一场连续降水进行研究.通过对降水样品的pH值和主要阴阳离子组成的测定,分析了贵阳地区酸雨的主要离子来源以及离子浓度随降水过程的变化规律等.结果表明,此次降水的pH值范围为3.65～7.20,平均值为4.24;SO42-是主要的阴离子,浓度加权平均值为119.06μeq·L^-1,占阴离子总量的80.63%;NH4^＋（38.38μeq·L^-1）和Ca^2＋（48.87μeq·L^-1）是主要的阳离子,分别占阳离子总量的37.82%和48.16%.Mg^2＋、Ca^2＋、NH4^＋与SO4^2-的相关系数分别为0.96、0.91、0.91,说明贵阳地区降水中可能存在以MgSO4、CaSO4、（NH4）2SO4为主的化学物质.大气中不同离子在降水过程被去除的方式和速率有较大的差别,在降水初始阶段,主要富存在粗颗粒中的Mg^2＋等离子,因粗颗粒迅速被冲刷而较快从大气中去除;而主要富存在细颗粒中的NH4^＋、SO4^2-等离子,因细颗粒冲刷速率较慢,而能够在大气中保存较长的时间.

英文摘要：

A study of the continuous precipitation in Guiyang has been taken during October 30 and November 7. The results showed that the range of pH was between 3. 65 and 7. 20,and volume-weighted mean was 4. 24. SO24 -was the main anion and volume-weighted mean was 119. 06 μeq.L -1 ,accounting for 80. 63% of total anions. While Ca^2 ＋ was the main cation and volume-weighted mean was 48. 87 μeq.L -1 ,accounting for 48. 16% of total cation and NH 4＋ was 38. 38 μeq.L -1 ,37. 82%. Good correlations between Mg^2 ＋ ,Ca^2 ＋ ,NH4 ＋ and SO42 -are observed,which may exist as MgSO4 ,CaSO4 and （ NH4 ）2 SO4 in the rainwater in Guiyang City. Different ions of the atmosphere had different scavenged ways and rate in the precipitation process. In the initial stage of precipitation,the ions such as Mg^2 ＋ ,which were rich in coarse particles,were quickly removed from atmosphere. However the ions such as NH 4^＋ and SO42^ -,which were rich in fine particles,could remain in the atmosphere for a longer time.