采暖季北京市主要大气污染物变化特征

为研究采暖季北京市主要大气污染物变化特征,收集北京市35个自动空气监测站点2013年11月至2014年4月上半月6种大气污染物的小时浓度均值,分析了其时间变化规律,并采用地理信息系统分析了污染物的空间分布特征.北京市采暖期间CO、NO2、SO2、O3、PM2.5和PM10的平均质量浓度分别为2.62 mg/m3、64.05μg/m3、50.52μg/m3、26.39μg/m3、118.61μg/m3和126.05μg/m3,其中：NO2的月均质量浓度变化较小；SO2和颗粒物的最高月均质量浓度都出现在2月；CO月均质量浓度呈现稳步下降的趋势；O3月均质量浓度则逐步上升. PM2.5、PM10、NO2和SO2的质量浓度日变化均呈双峰双谷型.对照点及区域点的O3质量浓度最高,其他种类污染物最高质量浓度出现在交通控制点.北京市大气污染物除O3外都呈现出南部质量浓度较高、向北部逐步递减的特点,O3在城区的质量浓度明显低于其他区域.

Characteristics of Main Atmospheric Pollutants in Heating Season of Beijing

The 1-hour average mass concentration of CO, NO2 , SO2 , O3 , PM2. 5 and PM10 from November 2013 to the first half of April 2014 obtained from 35 air automatic monitoring sites in Beijing was used to analyze temporal and spatial distribution of atmospheric pollutants. The results show that the average concentration for CO, NO2 , SO2 , O3 , PM2. 5 and PM10 in heating season was 2. 62 mg/m3 , 64. 05 μg/m3 , 50. 52 μg/m3 , 26. 39 μg/m3 , 118. 61 μg/m3 and 126. 05 μg/m3 respectively. The concentration of NO2 changes slightly, and the highest concentrations of SO2 and particulate matter are in February, CO shows a steady downward trend, while O3 is gradually increased. NO2 , PM2. 5 and PM10 concentration diurnal variation show a bimodal. With fine particulate pollution levels increased the proportion of PM2. 5 in PM10 and the concentrations of NO2 , CO, SO2 gradually rises, the O3 change trend is opposite. The concentration of O3 is the highest in comparative and regional stations respectively, while that of other pollutants is the highest in traffic pollution monitoring stations. The distribution of atmospheric pollutants mass concentration in heating season in Beijing is derived by the Original Kriging interpolation method, and it shows from the figure that the concentrations of PM10 ,PM2. 5 ,CO,NO2 ,SO2 gradually increases from the northern mountain area to the southern part of Beijing. O3 concentration in the urban area is significantly inferior to other regions.