The client of Chinanews.com (Lang Lang) May 15th, the Ministry of Ecology and Environment held a press conference. It was revealed at the meeting that the average concentration of PM2.5 in the "2 + 26" city (Beijing-Tianjin-Hebei air pollution transmission channel), the Yangtze River Delta region, and the Fenwei Plain in 2019 decreased by 13.6%, 16.4%, and 11.4% year-on-year, respectively, and the number of heavy pollution days Decreased by 36.2%, 58.0%, and 34.8%; the ambient air quality in autumn and winter in the three regions was the best in the past three years.