| The status of air pollution in Handan city was based on the online observation data of atmospheric particulate matters and gaseous pollutants at four air quality monitoring stations during 2013 and 2014, as well as the meteorological observation data. The results shows that the fine particulate matters were the key air pollutant in Handan. The annual average PM2.5 concentrations in 2013 and 2014 were respectively 139μg·m-3 and 116μg·m-3. Comparing with 2013, the PM2.5 concentration in 2014 was reduced by 16.5%, and at the same time, the over standard rate was also lowered from 74.4% to 66.6%. In addition, the over standard rate of PM10 dropped to 59.5% in 2014 from 76.8% in 2013. The over standard rate of NO2 dropped from 20.3% to 9.3%. And the seasonal variation characteristics of it was more obvious in 2014, which showed that the pollution level of autumn and winter was above that of spring and summer. The over standard rate of SO2 dropped from 83.0% to 4.9%, which was very evident. So the treatment effect of it in Handan was very obvious. The over standard rate of O3 dropped from 15.5% to 5.5%. And the over standard rate of CO dropped from 10.0% to 4.7%.There was no obvious difference in the spacial distribution of PM2.5 concentration in Handan. The PM2.5 concentration was highest in winter, followed by autumn, spring and summer, while the PM10 concentrations were in the order of winter> spring> autumn> summer. There were no clear differences in the concentration of PM2.5 and PM10 in a week, indicating that weekly changes are not obvious in the pollutant emissions and the relatively stable pollutant emission sectors, e.g., industries, played a key role.The pollution level of PM2.5 and PM10 in heating period was significant higher than that of before and after heating period.The concentrations of OC(organic carbon) and EC(element carbon) in PM2.5 showed some seasonal characteristics, which was winter > autumn > spring > summer, consistent with the seasonal variation of PM2.5. The OC pollution was even more serious. Comparing with 2013, the percentage of EC in PM2.5 fluctuated less in 2014.Correlation analysis between the meteorological condition and the pollutant concentrations indicated that the calm wind had the highest frequency in four seasons in Handan, and the wind direction was concentrated in the direction zone from the east to the south and to the west. Henan, Shandong and Shanxi contributed more to particulate matters of Handan.The regional source contribution in Handan was calculated by sawtooth wave analysis of typical pollution process. And the results showed: In 2013, the regional and local contributions to PM2.5 are respectively 47% and 53%; In 2014, the regional and local contributions to PM2.5 are respectively 49% and 51%. In two years, the regional source contributions in autumn and winter are higher than those of the local source. And the regional and local contributions in autumn are similar to those in winter.Through path analysis, the main factors that influenced the PM2.5 concentration variation were respectively PM10, SO2, NO2 and CO. Industry, coal and transportion are the main source of PM2.5 in Handan. |
PDF Full Text Request