云下颗粒物清除作用对雨水离子组成影响研究  

Contributions of Washout Process of Particles to Ion Concentrations in Rainwater

作　　者：谢鹏[1] 霍铭群[1] 孙倩[1] 刘兆荣[1] 白郁华[1] 李金龙[1] 

机构地区：[1]北京大学环境科学与工程学院,北京100871

出　　处：《北京大学学报（自然科学版）》2009年第4期707-712,共6页Acta Scientiarum Naturalium Universitatis Pekinensis

基　　金：国家重点基础研究发展计划项目(2005CB422204);国家高技术研究发展计划项目(2006AA06A309)资助

摘　　要：采集并分析了2007年深圳4月份3场降水和泰安郊区7月份4场降水离子组成,并测定了观测期间PM2.5和PM10中离子组成,研究颗粒物在云下冲刷过程对雨水中离子组分的影响。同泰安郊区相比,深圳雨水中主要离子浓度较低,雨水酸化较严重,云下冲刷对雨水中主要离子贡献较小。颗粒物的云下冲刷过程比较重要,PM10中Ca2+和Mg2+清除比较大,NO3-,NH4+和Cl-的清除比较小,气体SO2,H2SO4对雨水中SO24-的贡献使SO42-具有较高的清除比。The authors collected and analyzed three rainwater samples in Shenzhen in April and four rainwater samples in a rural area of Taian in July, 2007. The ion species in PM2.5 and PM10 concentrations were measured to get the influence of washout process of particles on ion concentrations in rainwater. Compared to that in Taian, the rainwater in Shenzhen showed higher ion concentrations and stronger acidity. The washout process made a more important contribution to ion concentrations in-rainwater in Taian than in Shenzhen, because Taian had a more serious air pollution. The washout process of particles was very important. The scavenging ratios of Ca^2＋ and Mg^2＋ in PM10 were high for Ca^2＋ , Mg^2＋ mostly existed in coarse particles. NO^-3, NH^＋4, Cl^- and K^＋ mainly existed in fine particles and had smaller scavenging ratios. SO2 and H2SO4 contributed a lot to the concentration of SO^2-4 in rainwater and therefore SO^2-4 had a high scavenging ratio.

关 键 词：降水 颗粒物 云下冲刷 清除比 

分 类 号：X51[环境科学与工程—环境工程]