北京市冬季大气颗粒物污染水平和影响因素研究

北京市大气颗粒物造成的城市空气污染仍是目前亟待解决的问题之一。为了分析北京市大气颗粒物的污染水平及其影响因素，作者以大气中的PM10 和PM2.5为研究对象，于2005年冬季在北京市范围内设立了5个功能区（9个采样点）进行采样监测。结果表明，北京市PM10 和PM2.5污染比较严重，不同区域的PM10 和PM2.5的污染程度为：交通干道区＞工业区，郊区＞商业区＞居民区，且PM2.5质量浓度的空间分布并不完全同于PM10；气象条件稳定时，PM10 和PM2.5质量浓度的日变化表现出一定的规律性，这种时间变化的特征主要取决于所在环境中排放的污染物变化情况；PM10 和PM2.5的污染程度受气象条件的影响：在一定的范围内，颗粒物质量浓度随着温度的上升而下降，随着相对湿度的升高而增加，随着风力的增强而降低，随逆温层的生成及增强而增高。

Atmosphericparticulates in Beijing city during winter

The air pollution caused by atmospheric particulates in Beijing city is one of the problems to be solved.In order to analyze the pollution level of atmospheric particulates in Beijing city and the influential factors,with the research on PM_(10) and PM_(2.5),the authors sampled at nine areas in Beijing city during winter in 2005.The results are concluded as follows.The pollution level in Beijing is very serious.Because of the influence of pollution sources at each sampling area,the pollution level of PM_(10) and PM_(2.5) in different regions reduces from main traffic road region to industrial region,decreases from rural region to commercial region to residential region,and not all the spatial distribution regulations of the concentrations of PM_(2.5) are the same as PM_(10).As weather conditions keep stable,the hourly variation of PM_(10) and PM_(2.5) concentrations presents regularly,the temporal variation mostly depends on the variety of contaminations released to the environment.Meteorological conditions are the important influential factors of PM_(10) and PM_(2.5) pollution level.A correlation analysis indicates significant negative correlation between the concentrations of atmospheric particulates and the temperature.And the same situation is also observed between the particle concentrations and wind speed.Positive correlation is found between relative humidity and the concentrations of atmospheric particulates.As the temperature inversion layer forms and becomes stronger,the concentrations of atmospheric particulates increase as well.