HONG KONG - China Merchants Holdings (International) Co doubled first-half profit because of rising container volumes and HK$1.37 billion ($176 million) of gains mainly linked to a stake in the operator of Shanghai's port.

Net income rose to HK$3.9 billion from HK$1.93 billion a year earlier, the Hong Kong-based company said in a filing to the Hong Kong Stock Exchange on Tuesday.

The one-time gains derived from a revaluation of the company's shares in Shanghai International Port (Group) Co, said a spokeswoman, Laura Huang, on Tuesday.

China Merchants' recurrent profit jumped 27 percent to HK$2.4 billion as rising shipments of Chinese-made goods to the United States and Europe boosted volumes at its port operations.

Growth may wane in the second half as rising job concerns slow spending overseas, according to Karen Li, an analyst at JPMorgan Chase & Co.

"China Merchants may be affected by weak demand in Western countries caused by economic uncertainties," she said. "The company's export focus also means volumes may grow more slowly than the industry average this year because domestic trade has been growing quickly."

China Merchants, the owner of stakes in ports moving about one-third of China's containers, declared an interim dividend of 30 HK cents a share, compared with 25 HK cents a year earlier.

The company's stock has lost 19 percent this year, compared with a 12 percent decline for the benchmark Hang Seng Index.

China Merchants' ports, which include facilities in Shanghai, Shenzhen and Ningbo, boosted first-half volumes by 11 percent to 27.6 million containers. Commodity volumes rose 19 percent to 160.5 million tons.

Cargo volumes at China's major ports increased 13 percent to 4.4 billion tons in the first half, according to the Ministry of Transport.

Sea harbors had a growth rate of 13 percent, while traffic at river ports jumped 14 percent.

China Merchants and partners signed a deal earlier this month to build and operate a container terminal in Colombo, Sri Lanka.

The project may cost more than $500 million.

Bloomberg News