(BEIJING, May 31) -- China's capital city has put in a total of 120 billion yuan (about 15.7 billion US dollars) to improve its environment since 1998 and the effort has been paid off, said Vice Mayor Ji Lin on Thursday.

"With the rapid social-economic development and despite the increase of population as well as of motor vehicles, Beijing's environment has been improving continuously," he told a press conference at the Beijing Olympic Media Center.

Firstly, the city's air quality has improved for eight years in a row. In 1998, there were only 100 days with good air quality, while last year saw 241 such days. The average density of sulfur dioxide and nitrogen dioxide in the atmosphere has met the national standard. The only area that did not meet the national standard is that of inhaled particulates.

The quality of the city's water has remained stable and now also meets national standards, while the emission of major pollutants is on the decline, Jin added.

He attributed the achievement to the city's continuing efforts to fight the threat of air pollutants.

For instance, Beijing has improved its energy consumption structure by using less coal and more clean energies such as natural and liquefied gas and others. The city consumed 300 million cubic meters of natural gas in 1998 and the amount has grown over ten times to 4.7 billion cubic meters in 2007.

In its endeavor to reduce vehicle emissions, Beijing will lead the nation in the implementation of the China IV standard in 2008 according to the 11th Five-Year social-economic development plan. "Beijing's vehicle number has surged to three million now, but our emission standard is growing too," he said.

In 2007, Beijing plans to eliminate 2,580 old buses, 5,000 taxis and revamp a number of high-emission vehicles being used by enterprises and government agencies, Ji said.

Beijing is also paying attention to sewage and trash disposal, and aims to treat 90 percent of waste water and 97 percent of solid waste in its eight core districts in 2007.