Calling all commuters

Persuading city slickers to take buses to work or airline passengers to buy 'carbon credits' are among the measures gaining Shanghai much praise as the city aims to shrink its carbon footprint and improve its air quality during next year's World Expo.

Whereas Beijing shuttered factories and upset production during last summer's 17-day Olympics in the capital, measures like these are not practicable for the six-month duration of the Expo, with 70 million visitors expected to start flooding into Shanghai from May.