Red tide off China coast

"XIAMEN, Jan. 16 (Xinhua) -- A red tide has hit the coast of Xiamen, a major city in southeast China's Fujian province, leaving masses of oysters and fish dead and the seas brown and smelly.

The red tide was caused by increasing temperature and recent projects to clear seabed sludge, which may have stirred up fertilizer residues in the seabed and given rise to algal blooms, the newspaper quoted marine experts as saying.

Red tides occur when pollutants such as raw sewage and fertilizers cause algae to bloom, sapping the water of oxygen and endangering marine life. "
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