大连市大气污染特征、影响因素及来源分析

CHARACTERIZATION OF CONCENTRATIONS,INFLUENCE FACTORS,AND SOURCES OF AIR POLLUTANTS IN DALIAN,CHINA

基于2016—2017年大连市6种大气污染物(PM_(10)、PM_(2.5)、SO_2、NO_2、O_3、CO)的监测数据,研究污染物浓度的时间变化、周末效应及气象影响因素。结果表明,大连市大气污染物以O_3、PM_(10)和PM_(2.5)为主;冬季主要污染物为颗粒物,夏季为O_3。受供暖燃煤等影响,PM_(10)、PM_(2.5)和SO_2浓度供暖季显著高于非供暖季。大气污染物浓度季节变化显著,且PM_(2.5)、PM_(10)、SO_2及NO_2呈现周末较高的"周末效应"。利用相关性分析考察温度、湿度、风速等气象因素对污染物的影响;利用后推气流轨迹等方法分析大连市大气PM_(2.5)可能的来源。

The atmospheric concentrations,temporal variations,workday and weekend effect,and their influence factors of six air pollutants（ PM10,PM2.5,SO2,NO2,O3 and CO） were studied,based on the continuous observation data in Dalian from2016 to 2017. The main air pollutants in Dalian were O3,PM10 and PM2.5. Particulate was the main pollutant in winter,while O3 was the main pollutant in summer. Concentrations of PM10,PM2.5 and SO2 were significantly affected by the emission from coal combustion in the heating season,and significantly higher than those in the non-heating season. Significant seasonal variations were found for PM,SO2,NO2 and O3 in Dalian,while obvious weekend effect was found for PM2.5,PM10,SO2,and NO2 with the concentrations higher at weekends than on workdays. We studied the influence of meteorological factors,such as temperature,humidity,and wind speed,on the concentration of contaminants by using correlation analysis. Potential sources of PM2.5 in Dalian were also estimated based on the back trajectory analysis.