Who are the main sources of air pollution?

Motor vehicle exhaust, industrial production, coal burning and dust, it seems difficult to determine how much each of these four contributes to the air pollution in most cities in my country. Who occupies the top spot? .

However, yesterday, the Ministry of Environmental Protection completed the analysis of air pollution sources in nine cities in my country, and preliminary results were obtained. The results show that the primary pollution source in Beijing, Hangzhou, Guangzhou and Shenzhen is motor vehicle exhaust, the primary pollution source in Shijiazhuang and Nanjing is coal burning, and the primary pollution sources in Tianjin, Shanghai and Ningbo are dust, mobile sources and industrial production respectively. So who is the culprit causing air pollution in Xi'an?

Sun Yuqi, Deputy Director of Xi'an Environmental Monitoring Station: In the winter, the primary pollutant in Xi'an is mainly PM2.5. The main source of PM2.5 is coal burning. In the spring and autumn, the primary pollutant is PM2.5. Mainly PM10, and the main source of PM10 is dust, road dust and construction dust. The primary pollutant in summer is ozone. The main source of ozone is vehicle exhaust and the emission of various volatile gases.

Webmaster Sun said that Xi'an will conduct an analysis of the sources of primary pollutants at the end of this year. By then, it will also be able to provide specific support for the scientific control of air pollution like the Beijing-Tianjin-Hebei region. According to the latest monitoring data, Xi'an's air quality continued to improve in the first quarter of this year.

Sun Yuqi, Deputy Director of Xi'an Environmental Monitoring Station: There were 52 days of good weather in the first quarter of 2015, an increase of 38 days compared to 2014.

Compared with the same period in 2013, the number of good days increased by 47 days. Among the 74 key cities in the country, Xi'an's air quality ranking has dropped out of the bottom ten. Next, Xi'an will continue to strengthen the prevention and control of dust, motor vehicles, coal burning, straw waste burning, etc.