2014—2016年昆山市NO_2时空分布及其源汇分析

NO_2 temporal and spatial distribution and source/sink analysis in Kunshan City from 2014 to 2016

利用昆山市12个环境空气自动站采集的大气数据进行统计研究,对昆山市近地层大气中NO_2时间序列变化、空间分布特征进行分析和研究。结果表明:(1)昆山市各功能区NO_2浓度分布不均,NO_2年平均值中心城区、开发区较高,郊区最低;分季节来看,3年春、夏、秋、冬季平均值分别为36.4、26.8、38.8、44.1μg/m^3,呈现冬高夏低、春秋过渡的规律。(2)2014年,NO_2浓度大致呈北高南低分布。2015年,第二中学站处于污染浓度高值中心;锦溪站浓度略有升高;其他各站点浓度都出现了不同程度下降。2016年,昆山市NO_2污染进一步改善,除开发区及花桥站和锦溪站外,各站点浓度均持续下降。(3)昆山市工业源对于NO贡献较小,而汽车等流动源对于NO影响相对明显。

Based on the statistical study on atmospheric composition collected from 12 ambient air quality monitoring stations in Kunshan City,the temporal and spatial distribution characteristics of NO2 in the atmosphere in the surface layer were also analyzed and studied.The results showed that:(1)the concentrations of NO2 in the functional areas of Kunshan City were uneven,the annual mean concentration of the central districts and the development zones higher,and the suburbs the lowest.In terms of seasons,the average values in spring,summer,autumn and winter reached 36.4,26.8,38.8,44.1μg/m^3.The values presented in the pattern of higher concentration in winter than in summer with spring and autumn interim.(2)In 2014,the concentration of NO2 was approximately distributed by higher concentration in the north than in the south.In 2015,the Second Middle School station was the center of high pollution concentration,the concentration of Jinxi station increased slightly,and the concentration of other stations decreased to some degrees.In 2016,the NO2 pollution in Kunshan was further improved.Except the development zones togerther with Huaqiao station and Jinxi station,the concentration of other stations reduced continuously.(3)Kunshan industrial sources contributed little to NO,while mobile sources such as automobiles posed relatively noticeable effects on NO.