BEIJING, Aug. 17 (Xinhua) --Beijing began a four-day experiment early on Friday to test whether pulling 1.3 million cars off roads daily would be of effect in enormously bringing down air pollution.

Experience obtained herein will in turn shed light to adoption of measures to guarantee environmental quality at the Olympic Games held in the Chinese national capital next year, according to Du Shaozhong, deputy director of the Municipal Environmental Protection Bureau.

In accordance with an action plan for the four-day test, from 6 a.m. to midnight on Friday, car drivers with even-numbered license plates face fines if they take to the city road.

In the meantime, odd-numbered cars will be banned on Saturday and Monday, while vehicles with even-numbered registrations must stay off the roads on Sunday.

The test seemed to produce initial positive results.

There were fewer motor vehicles in the city during rush hours on Friday morning, and office workers who rode in shuttle buses on the day arrived in offices much earlier than usual.

Mr. Xu, who lives in a town house in Daxing District and owns an off-road Honda vehicle with an even-numbered registration, usually drives to his office located in Xicheng District, downtown Beijing.

However, he had to leave his car home on Friday morning and ride instead in a shuttle bus arranged by the residential compound to Fuxingmen in downtown Beijing, about 15 minutes' walk from his office.

"I think it is a nice experience as I can relax my nerve and take more exercise without driving," said Xu.

A spokesman with Beijing Public Transport Holdings Ltd. said that with the introduction of the alternate-day practice, the usually-clogged city roads were suddenly filled with fewer motor vehicles on Friday, so the efficiency of the public buses was improved by 7 to 15 percent as a result.

Liu Xiaoming, deputy director of the Municipal Transportation Commission, said during the test period, 10,000 bus runs would be increased daily to help ease the pressure caused by a sudden surgeof passengers, and running times would be extended for an hour.

And 1,600 taxis will be allocated to train stations and airports each day and more than 300 taxis will stay at more than ten venues of the "Good Luck Beijing" Olympic test event, according to the Municipal transportation commission.

It is estimated that 8.4 million people will take public transport, including buses, the subway and taxis, in the four days compared with 6.4 million on average.

Beijing has more than three million vehicles and more than four million drivers.