High tides were gradually getting higher according to records, said Li Wuquan, head of the State Oceanic Administration's Beihai Oceanic Environment Monitoring Center.

Global warming was believed by experts to be a key cause of the rising seas, but there were also human factors. The protective coral reef has been destroyed by the taking of coral for money and fishing with explosives. Tourist diving at scenic sites also affected the reefs.

"Little remains of the coral reef, which helped prevent erosion in the shore area around the island," said Jiang.

The official said the township government had banned fishing with explosives near the reef and been cracking down on coral harvesting. Some coastal areas have been listed as special protection areas.

According to a 2007 Sea Level Bulletin released by the State Oceanic Administration earlier this year, the seas rose by 0.09 meter on average around China over the last 30 years, but the rate was accelerating.

Sea levels have been predicted to rise between 9 and 88 centimeters this century due to global warming.

The hollowed-out tree trunk flushed by rising sea water is seen on a beach of South China's Weizhou Island.

(Xinhua News Agency August 30, 2008)