北京市2009年8月大气颗粒物污染特征

为研究2008年8月北京奥运会1a之后北京市大气颗粒物的污染特征,于2009年8月对北京市大气颗粒物PM10、PM2.5样品进行采集,测量其质量浓度并对其中的水溶性离子组分进行分析.研究发现2009年8月北京市大气颗粒物PM10、PM2.5质量浓度日均值分别为176.9μg/m3和102.5μg/m3.PM10质量浓度...

Characteristics of particulate matter pollution during August 2009 in Beijing

In order to investigate the characteristics of air quality of atmospheric particulate matter pollution in Beijing one year after the 2008 Olympic Games, particulate matter samples were collected in Beijing during August 2009. The daily mass concentrations of particles were measured and ions in them were also analyzed. Results showed that the mean daily mass concentrations of PM10 and PM2.5 in Beijing were 176.9 μg/m3 and 102.5 μg/m3 in August 2009, respectively. The concentrations of PM10 in 2009 were 180% higher than those in the same period of 2008 and 10% lower than those in 2007. The observed PM2.5 concentrations in 2009 were 126% higher than 2008 and 31% higher than 2007. Water-soluble ions were the major components and accounted for 43% and 61% of PM10 and PM2.5, respectively. The ratios of PM2.5/PM10 and NO3-/SO42-were much higher in polluted days than those in clear days, and the local mobile emission was the major polluted source in Beijing. The concentrations of PM10 and PM2.5 were significantly influenced by the weather conditions such as wind speed, wind direction and the rainfall process. Heavy particulate matter pollution was presented in case of southeast wind with wind speed of 0.5~1.0 m/s.