BEIJING - Global container freight volumes will increase this year, but in a slower growth rate compared with 2010, according to a report released by the Chinese Academy of Sciences (CAS).

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The ongoing European debt crisis, frequent natural disasters and continuing fallout from the global financial crisis have brought uncertainties to this year's container shipping market, said Wang Shouyang, head of the CAS's Center for Forecasting Science.

Wang said that he expects a slowdown in global container freight volume this year, as the United States is still recovering slowly and Europe "has insufficient internal impetus to drive economic growth."

The report also said that China will continue to stay on top in terms of container throughput. Shanghai will maintain its position as the world's busiest container port this year, due to the country's robust economic growth and massive foreign trade volume, according to the report.

Half of the world's top 20 ports will be Chinese ports this year, compared with nine in 2010.

Container throughput is a gauge of a port's importance in international trade and a key barometer for global economics and trade.