The level of environmental awareness among Beijing residents has fallen for the third consecutive year, a new survey shows.

Despite the frequent environmental protection debates and scandals, especially over water and air quality, environmental awareness of Beijing residents — not only general knowledge of environment issues but participation in them — failed to grow last year, according to a survey by the education center under the Beijing Municipal Environmental Protection Bureau released on Thursday.

Local residents' environmental awareness in 2012 was 71.6 points out of a possible 100, compared to 72.2 points in 2011, 74.2 points in 2010 and 75.9 points in 2009.

Conducted in December 2012, the survey covered about 2,000 residents 16 and 60 years old who have lived in the city for at least two years.

"The environmental protection issue has been heatedly debated in recent years, but people's awareness has decreased since 2009," said Liu Jingqi, the survey's project director.

"One of the reasons for the peak of people's awareness in 2009 and decrease afterwards was Beijing's hosting the Olympic Games in 2008, when government promotion greatly spurred people's consciousness," Liu said.

Though people are attaching more importance to air and water quality among all environmental issues recently, poor execution and action have contributed to decreasing environmental-protection awareness.

"Many in the public practice energy conservation by saving water or electricity consumption, but the performance is not as good when it comes to disposable tableware, overpacked products and other issues," said Liu.

In addition, despite the fact that PM2.5, or particulate matter with a diameter smaller than 2.5 micrometers, has been hotly debated in recent years, the number of people knowing this term is relatively small among Beijing's 20 million residents.

Only 24.2 percent of those interviewed said they had heard of the term PM2.5, and half of those who had heard of it did not know the term is related to air pollution, according to the survey results.

Zhou Rong, director of the Greenpeace climate and energy project in Beijing, echoed the center's conclusion.

"Despite the intense promotion of the content and hazards of the fine particulate through the media in recent years, many of the public only have a general or even vague recognition of it without comprehensive understanding," she said.

Zhou said even when the PM2.5 index was "extremely hazardous" to people's health, most people outdoors were not wearing any mask or other protection measures.

However, Zhou said the survey could better guide the public in boosting their consciousness in protecting the environment and themselves.