The action may help the city, which has more than 1.7 million motor vehicles, to reduce major pollutants by half, the State Environmental Protection Administration (SEPA) said Thursday.

This is just the latest measure to clean the air breathed by the city's 12 million residents.

Uncontrolled car emissions, coal burning, smoke from factories and dust used to make Beijing one of China's worst cities for air pollution. But, after the government took a series of measures such as closing down some heavily polluted enterprises and adopting natural gas instead of coal, the environment here has been greatly changed.

Beijing has become an obvious beneficiary of China's long-term pursuit and final winning of the 2008 Olympic Games. China has promised to make a "green" event.

But it is not the only force for environmental improvement in Beijing. The city's efforts to clean the air and the water are part of an overall drive for sustainable development.

In a recent campaign, law enforcement officers of environmental protection departments across China investigated more than 6,300 enterprises which illegally discharged excessive pollutants. Some 800 heavy polluters were closed down.

Chinese Premier Zhu Rongji has repeatedly underlined the importance of environmental protection, saying that environment issues are critical to the success of the country's modernization drive, and even the revitalization of the Chinese nation.

"China must go along the path of sustainable development," he told a national conference on environmental protection early this year.

Foreseeing the environmental impacts of rapid industrialization,urbanization and population growth, China's policymakers now regard sustainable development as a guiding strategy in its economic and social development.

The Chinese government will invest 700 billion yuan (US$85 billion) in environmental protection projects in the 2001-2005 period, almost double the investment in the previous five years.

"We should do our best to halt the tendency of ecological degradation through reducing discharges of pollutants and dealing with the pollution in the water and the air," said Xie Zhenhua, director of the SEPA.

He said China should be able to achieve a win-win result both in economic development and environmental conservation.

The central government has just kicked off a decade-long "grain-for-environment" program, in which farmers will be compensated with grain and cash for laying their farmland fallow which is low-yield and vulnerable to soil erosion due to lack of vegetation.

Although it is enormously costly, with 100 billion yuan (US$12 billion) in total investment, the program is designed to curb soil erosion and to help restore the ruined ecosystem.

And it is not only the government that has taken action.

The National People's Congress, China's highest legislative body, passed a law on clean production last month, urging enterprises to adopt environment-friendly methods in industrial production.

Non-governmental organizations are also burgeoning throughout the country to promote understanding of environmental conservation among the public.

A United Nations report issued here last month said China is at a crossroads of sustainable development, and the choice it makes will be significant to the whole world.

But it acknowledged that China has started making positive changes.

"The choice is clear. The Chinese people desire a sustainable future, a green future," it said.

(People's Daily July 26, 2002)