摘要
本研究分析了北京冬季一次大气重污染过程的颗粒物污染特征,通过数学统计方法分析了其形成的可能原因.观测于2013年1月24—31日进行,在西三环城区和大兴郊区使用中流量大气颗粒物采样器采集可吸入颗粒物(PM10)和细颗粒物(PM2.5),并采用离子色谱和元素碳/有机碳分析仪分析了PM2.5上的水溶性离子、元素碳和有机碳浓度.结果表明,本次重污染天气的大气日均能见度低于3.0 km.PM10和PM2.5质量浓度日均最大值分别为675.5和453.4μg·m-3,平均质量浓度为349.2和260.8μg·m-3,超过环境空气质量标准(GB3095—2012)所规定的二级浓度限值.通过比较PM2.5上化学成分的浓度发现,在城区和郊区,此次天气形成的共同污染源为冬季燃煤燃烧、汽车尾气排放和二次有机气溶胶污染;而土壤/沙尘对郊区污染天气的形成有部分贡献.大气中PM2.5质量浓度与能见度呈对数负相关关系.
This study aimed to investigate the pollution process and statistically analyze possible reasons for a high pollution episode in winter. Atmospheric coarse and fine particulate matter （PM10 and PM2.5） were collected at urban and suburban locations of Beijing from 24 to 31 January, 2013. The mass concentration of PM10, PM2.5 and the concentrations of ions, elemental carbon （EC） and organic carbon（OC） in PM2.5 were measured and their correlations with visibility were studied. The results showed that daily visibility was less than 3 km during heavy air pollution episode. The maximum daily mass concentrations of PM10 and PM2.5 were 675.5 and 453.4 μg·m^-3. In addition, the average daily mass concentrations of PM10 and PM2.5 were 349.2 and 260.8 μg·m^-3, exceeding the ambient air quality standard （GB3095—2012） of China. The main contribution sources to the formation of heavy air pollution were coal-burning, vehicle exhaust and formation of secondary organic aerosol, based on the comparison between chemical compositions in PM2.5 during the pollution episode. Significantly negative correlations were observed between mass concentrations of PM2.5 with visibility.
出处
《环境科学学报》
CAS
CSCD
北大核心
2014年第1期12-18,共7页
Acta Scientiae Circumstantiae
基金
国家自然科学基金面上项目(No.41175104)
中国科学院灰霾项目(No.XDB05030103)
中国科学院大气物理研究所大气边界层物理与大气化学国家重点实验室开放基金
北京市科学技术研究院青年骨干人才计划项目(No.201301)~~
关键词
北京市
冬季
大气颗粒物
污染特征
能见度
Beijing
winter
atmospheric particulate matter
pollution characteristics
visibility
作者简介
刘庆阳（1982-），男，助理研究员，E-mail：liuqingyang1982@126．com
通讯作者（责任作者），E-mail：liuyanju@hotmail．com责任刘艳菊（1969-），女，北京市理化分析测试中心研究员，主要研究方向为大气环境化学及环境生物学
