Reconstruction from the March 11 disaster that destroyed or damaged more than 150,000 buildings may boost volumes for dry-bulk shipping lines struggling with global overcapacity.

"The rebuilding process will need big volumes of material," Wei Jiafu, chairman of China Cosco (Holdings) Co., China's biggest dry-bulk operator, said Wednesday in Hong Kong at an earnings news conference. In the short term, the industry faces "severe challenges" because of the increasing size of the global fleet, he said.

Japan may increase imports of Australian iron ore and of logs and lumber from New Zealand and Malaysia after the March 11 tsunami devastated buildings in the Tohoku region. Following the Kobe quake in 1995, the Baltic Dry Index, the benchmark for commodity-shipping rates, surged 20 percent in three months after initially falling 6 percent in three weeks.