Beijing municipal government's decision to limit the number of motor vehicles on the city's roads during a four-day test, which starts this weekend, demonstrates its resolve to address the problems of congestion and pollution caused by emissions.

This is undoubtedly a simple but effective remedy for the problem. But it can only be executed as a provisional measure for a particular purpose over a certain period of time - like hosting the Olympic Games, for example.

A simple methodology can only bring about a simple solution. It does not touch the root cause of the conundrum.

Dramatically reducing the number of vehicles on Beijing's roads is definitely the most effective way to smooth the traffic and thin out the exhaust in the air but administrative prohibitions are not the right way to permanently solve the problem.

To dissuade people from driving and persuade them to take public transport, the government should study the psychology of motorists and take appropriate measures.

Most drivers are aware of the seriousness of air pollution and their contribution to it. But the awareness, or even guilt, is not strong enough for them to give up driving unconditionally.

They cannot do without the convenience and comfort of their own car. If the cost of driving becomes high enough, however, they might be less inclined to use their vehicles.

Two measures can be taken to this end.

First, charging a fee for driving in the inner city - within the third or fourth ring roads, for example.

Second, charging a pollution fee.

The pollution fee is verifiable. Car owners account only for a minor proportion of the total population. It is unfair for non-drivers to suffer polluted air when it is not their fault. Charging car owners to finance causes of public good is a kind of compensation for the non-owners.

Some people might argue that an inner city fee would benefit the rich and deprive ordinary citizens' right to auto mobility. But it is not.

What would be restricted is driving on crowded roads in densely populated areas, which is far from a pleasant business. If the rich enjoy driving in such conditions, let them do it and pay for being part of the congestion. Of course, the charge should be set very high.

Technical feasibility is not a problem.

Another reason why motorists do not like public transport is that it is inconvenient and takes longer.

Commuters might have to change trains or buses two or three times to get to their destination. Buses and subway trains are invariably crowded and waiting at bus stops can be chaotic.

Many people have tried public transport but returned to their private vehicles for the reasons given above. If the problems are solved, many commuters will opt for public transport.

To settle these problems and ensure a fast, effective and orderly public transport system needs government action. However, campaign-style promotions and empty slogans won't do.

Careful investigation and meticulous planning of corresponding measures are needed. The authorities even need to study the psychology and habits of commuters so as to take really effective measures to attain the desired results.

A conundrum's solution calls for conscientious effort.

Email: liushinan@chinadaily.com.cn

                                  (China Daily 08/15/2007 page10)

劉式南 高級(jí)編輯。1968年畢業(yè)于武漢華中師范學(xué)院（現(xiàn)華中師范大學(xué)）英文系。1982年畢業(yè)于北京體育學(xué)院（現(xiàn)北京體育大學(xué)）研究生院體育情報(bào)專業(yè)。1982年進(jìn)入中國(guó)日?qǐng)?bào)社，先后擔(dān)任體育記者、時(shí)政記者、國(guó)際新聞編輯、要聞版責(zé)任編輯、發(fā)稿部主任、《上海英文星報(bào)》總編輯、《中國(guó)商業(yè)周刊》總編輯等職。現(xiàn)任《中國(guó)日?qǐng)?bào)》總編輯助理及專欄作家。1997年獲國(guó)務(wù)院“特殊貢獻(xiàn)專家政府津貼”。2000年被中華全國(guó)新聞工作者協(xié)會(huì)授予“全國(guó)百佳新聞工作者”稱號(hào)。2006年獲中國(guó)新聞獎(jiǎng)二等獎(jiǎng)（編輯）。