浙江省杭州市城西大气污染物变化特征及相关性研究

Variation and correlation of air pollutants in the west of Hangzhou City, Zhejiang Province

利用浙江省杭州市西溪监测站2014年12月1日到2016年11月30日的监测数据,分析了6种大气污染物(SO_2、NO_2、CO、O_3、PM_(2.5)和PM_(10))的变化特征及其相关性,探讨了气象条件对污染特征的影响。结果表明:1)研究期间SO_2和CO达到了空气质量一级标准,但NO_2、PM_(2.5)和PM_(10)超标严重,平均浓度分别是二级标准的1.21、1.40和1.04倍。2)除O_3外,其余污染物均呈冬高夏低的变化特征,而O_3浓度为夏高冬低;大气氧化性O_x冬季受NO_2主导,其余季节受O_3主导。3)PM_(2.5)与NO_2、CO浓度呈显著正相关,其次与SO_2、O_x(夏季)也存在较强的正相关性。4)温度与O_3呈较强的正相关,而与其他污染物呈负相关;相对湿度、风速和降雨量与SO_2、NO_2、CO、PM_(2.5)和PM_(10)存在负相关性,而CO受相对湿度和降雨量影响较小。该研究可为杭州市大气污染控制提供理论依据。

Based on the concentrations of SO_2,NO_2,CO,O_3,PM_(2.5)and PM_(10)measured by Xixi monitoring station,meteorological data such as temperature,relative humidity,wind speed,visibility and rainfall,variation characteristics and correlations of various air pollutants in Hangzhou City from December 2014 to November2016 were analyzed,and the influence of meteorological conditions on pollutants was discussed.The results showed that the concentrations of SO_2and CO reached the first grade standard of air quality during the study period.NO_2and particulate matter were severely over-standard and the average concentrations of NO_2,PM_(2.5)and PM_(10)were 1.21,1.40 and 1.04 times of the second grade standards,respectively.The concentrations of all pollutants were high in winter and low in summer.However,the concentration of O_3was high in summer and low in winter.Atmospheric oxidative O_xremained at a relatively stable level throughout the year and was dominated by NO_2in winter and O_3in other seasons.The concentration of PM_(2.5)was positively correlated with that of NO_2and CO,followed by SO_2and O_x(in summer),which indicated that the local vehicle exhaust emission was an important source of atmospheric particulates.The temperature was positively correlated with O_3,and negatively correlated with other pollutants.Relative humidity,wind speed and rainfall were negatively correlated with SO_2,NO_2,CO,PM_(2.5)and PM_(10),which showed that the pollutants were easy to diffuse under strong wind and wet deposition condition.However,CO was less affected by humidity and rainfall.This study provides a theoretical foundation for controlling atmospheric pollution in Hangzhou City.