In the first quarter of last year, the company which Wang works for ran at only one-third capacity as the global downturn accelerated, said Shi Libo, head of the company's control center. "This year we have added more than 50 trucks, but we are still under pressure."

He Jianzhong, a Ministry of Transport spokesman, told Xinhua port cargo throughput and foreign trade cargo throughput rose more than 20 percent year on year in the first quarter, indicating strong domestic demand and accelerated economic growth.

Government data shows that the first quarter saw robust throughput of commodities like iron ores, coal and crude oil, boosted by growing domestic demand which came on the back of rapid growth in fixed-asset investment, rising power generation and booming auto sales.

Some 173 million tonnes of iron ore imports were moved at Chinese ports in the first quarter, up 16 percent from a year earlier, according to government statistics. Unloaded imports of crude oil at Chinese ports, meanwhile, rose 30 percent to 48.42 million tonnes.

Customs authorities said Saturday China's exports rose 24.3 percent in March to 112.1 billion dollars from the same month a year earlier, while imports soared 66 percent year-on-year to 119.3 billion dollars. In the first quarter, foreign trade rose 44.1 percent to 617.85 billion U.S. dollars.

However, Huang Weiping, secretary of the board of directors of Ningbo Port Co., said the strong growth in the first quarter was due to the low base, with actual throughput not having increased from the pre-crisis levels of 2008.

"We can't be blindly optimistic about the current situation as the domestic and international economic environment are still complicated," he said.

The central government has repeatedly warned of the economic uncertainties both at home and abroad and announced in March it will target 8 percent economic growth in 2010, the year described by Chinese Premier Wen Jiabao in early March as "a crucial but complicated year for China's economic development."