The head of China's oceanic authority has said that the outlook for China's maritime environment is "not optimistic," calling for further efforts to build the ocean conservation culture.

Major tasks include upgrading traditional industry, evaluating the maritime environmental carrying capacity, controlling the total amount of pollutants, and improving the monitoring system, said Liu Cigui, director of the State Oceanic Administration (SOA).

Liu added that certain achievements have been made in energy conservation, emissions reduction and pollution control. However, the outlook for the maritime environment is not optimistic in general, as it is still facing major challenges.

Due to the rapid economic expansion and development of maritime resources, labor-intensive industries and industries with high consumption in energy and resources are polluting the country's marine belt, Liu said.

The development of the heavy chemical industry, especially coastal and offshore oil and gas exploitation, brings risks to the maritime environment, as chances for oil and chemical leaks are growing.

In the meantime, the depletion of oxygen in water is another challenge facing the maritime environment, Chen said, adding that a total of 14,000 square km of algae bloom was found from 2005 to 2010.

According to Liu, environmental protection and control, as well as ecological rehabilitation in the Bohai Sea, will be the focus for the SOA's work this year and for some time to come.

The country's semi-closed Bohai Sea suffered heavy pollution last year as an oil leak took place at the Penglai 19-3 oilfield run by ConocoPhillips China, a subsidiary of U.S. energy giant ConocoPhillips.

The oil spill has polluted over 6,200 square km of water in the bay since June, an area about nine times the size of Singapore. The SOA later said that its investigation revealed that operations in the oilfield were in violation of the region's development plan.