About half of China's marine zones were deemed polluted last year, especially in the coastal areas, according to survey results released yesterday by the State Oceanic Administration.

Of the 18 coastal ecological monitoring zones, six were deemed unhealthy; seven, moderately healthy; and only five, healthy.

Heavily-polluted areas include Liaodong Bay in northeast China, Bohai Bay in northern China, the Yangtze River estuary, Hangzhou Bay and coastal areas in Jiangsu Province in east China and the Pearl River estuary in southern China.

More than 27,000 square kilometers of sea was covered by 82 red tides, costing the fisheries industry a direct loss of more than 69 million yuan (US$8.6 million).

However, the red tides did not cause human loss or injury thanks to monitoring and early warning systems.

Populations in coastal provinces account for 40 percent of the country's total, and about 382,000 square kilometers of water comes under China's sovereignty. The major pollutants are inorganic ammonia, active phosphate and petroleum. In some marine zones, heavy metals such as lead and cadmium exceeded safety limits.

"Wastewater discharge and over-fishing are the two major reasons for ecosystem degradation in coastal marine areas," according to Ma Deyi, director of the National Marine Environment Monitoring Center.

Results from the country's 200 coastal monitoring stations indicate that more than 317 billion tons of wastewater were discharged into the ocean from the mainland in 2005, almost twice as much as in 2000.

"Some 270 waste water discharge points were found in fishing areas, posing a great threat to the safety of marine life and the quality of seafood; and another 70 were found in scenic areas, threatening surrounding natural environments," Ma said.

In other development, top Chinese environmental protection officials have for first time listed water pollution control in the Songhua River's drainage area as one of the country's key water pollution control and prevention projects.

A draft of a control plan says that priority will be given to the water sources of large and medium sized cities along the Songhua River, along with achieving the ultimate ecological goal of a healthy standard of clean water in each river section.

(China Daily January 10, 2006)