BEIJING, Nov. 2 (Xinhua) -- Beijing witnessed a year-on-year decline in the density of hazardous fine particle matter PM 2.5 in the first nine months this year, local authorities said Thursday.
The city's average PM 2.5 density dropped to 60 micrograms per cubic meter in the first three quarters, down 3.2 percent compared with the same period last year, and down 34.8 percent compared with 2013, according to the Beijing Municipal Environmental Protection Bureau.
As winter arrives, Beijing faces months of heavier air pollution due to heating by coal burning.
From January to September, 16,000 heavy-duty diesel vehicles were fined a total of 7.25 million yuan (1.1 million U.S. dollars) for excessive emissions.
Beijing's 5.8 million vehicles produce more than 10 tonnes of nitrogen oxide and hydrocarbon compounds annually. Heavy-duty diesel vehicles only account for 4 percent of the total vehicles in the capital, but discharge half of the nitrogen oxide, and 90 percent of particulate matter from car exhausts.
The city has made increased efforts to deal with pollution in recent years. In 2017, it will decrease coal use by helping 700 villages move to clean energy, removing 300,000 vehicles from roads, and shutting down 500 factories.