Nation embraces action to help eradicate pollution and further promote the government's eco-friendly model for development. Hou Liqiang reports.

Sometimes, the smog was so heavy that people could hardly get a clear view of buildings just across the street. Many residents stored lots of particulate masks, and some even wore respirators outdoors.

That's how Ma Jun, director of the Institute of Public and Environmental Affairs, an NGO, remembers the poor air quality in Beijing more than a decade ago.

While the particulate-filtering face masks Ma bought at the time have remained idle for a long while, they serve as reminders of the terrible air pollution in days gone by.

As Beijing enjoyed sustained clear, crisp air during the recent Winter Olympic Games, Ma marveled at the changes that have happened. "The improvement is huge and marked," he said.

According to official data, in 2013－the year Beijing started monitoring levels of PM2.5 particulate matter－the annual average density of the pollutant in the city was 89.5 micrograms per cubic meter.

Ma noted that the figure fell to 33 mcg per cu m last year, and when the Games opened on Feb 4, it was just 5 mcg per cu m.