(Xinhua)
Updated: 2008-06-08 16:45

BEIJING  -- One of China's top experts in marine economic geography has warned that pollution of China's seas is still serious despite slightly improved offshore water quality.

"Over the past 20 years or so, China's marine economy has been developing at a staggeringly rapid pace and marine resources are being widely tapped. As a result, the condition of China's inshore environment is deteriorating and the ocean ecology has been seriously damaged," said Professor Luan Weixin, of the Economics and Management College at Dalian Maritime University.

A total of 145,000 square kilometers of shallow waters along China's vast coast failed to meet quality standards for clean oceanic water, of which 29,000 square kilometers of seawater were seriously polluted.

These severely-polluted water areas included East Liaoning, Bohai and Hangzhou bays, and the estuaries of Yellow, Yangtze and Zhujiang rivers, as well as inshore areas of major coastal cities, he said.

"Content of major pollutants, such as inorganic nitrogen and phosphate, remains high in contaminated seawater," Luan told a seminar on marine function zoning, in the northern Chinese coastal city of Tianjin.

During the past 50 years or so, the inshore ecosystem had seen 50 percent of coastal wetlands disappear in excessive reclamation and 80 percent of coral reefs and mangroves destroyed, Luan said.

China's marine economy had been soaring annually at more than 20 percent since the 1980s and the total output reached 2.5 trillion yuan (359 billion US dollars) last year, 266 times more than that of 1979.

China's mainland coastline is about 18,000 kilometers long. Under the UN Convention on the Law of the Sea, China boasts about 350,000 square kilometers of coastal and inland water areas, and the area of China's  exclusive economic zone is about 3 million square kilometers.