The red tide is the first of the year for the province.

It has already killed several thousand of the highly-prized fish called groupers, costing local fishermen a fortune.

The red tide, covering an area of more than 300 square kilometers at one point, was unusual because it arose during the province's flood season, instead of a low-flow period, said a local water resource official.

According to the official, who declined to be named, red tides have become commonplace in the offshore waters of Guangdong in the past decade as its coastal environment deteriorates. But he said most red tides occur in the dry season when there is insufficient run-off to dilute the huge amount of sewage discharged from the land.

Some 1.2 million tons of pollutants were carried into the sea by the Pearl River last year.

The official said the red tide could be a forewarning of drought in Guangdong this year.

"Red tides in flood seasons, instead of dry seasons, are historically proven predictors of severe drought in the province later in the year. And the province's rainfall for this year lends extra support to this prediction," he said.

All but a few of the province's 1,000-odd hydrometric stations recorded zero rainfall this spring.

This explains why most of the province's rivers are reporting record low water levels. Several of them have water levels 5 to 6 meters lower than only 10 days ago, said the official.

Because of the scarce rainfall, many counties of Guangdong have had difficulties sowing crops for spring.

For instance, 2,000 of the 13,340 hectares of rice fields in Huidong County could not be planted with seedlings, while 59 per cent of the remaining land had to rely heavily on water pumps.

A similar crisis affected the Lianjiang, where 1,334 hectares of paddy fields had to be turned over to more drought-resistant plants.

Local authorities have been told to prepare for even worse drought later this year, said the official.

(China Daily May 5, 2003)