Scientists from China and New Zealand are closely monitoring Taihu Lake to prevent another outbreak of blue-green algae.

An outbreak last year resulted in 2.3 million people in Wuxi, Jiangsu Province, suffering from a drinking water shortage.

A 24-hour wireless water quality observation system has been deployed in parts of the lake.

It gives a reading every 10 minutes on oxygen and chlorophyll content, vital to the notification of algae build up, scientists said yesterday at the China-New Zealand Science to Market Conference in Beijing, held by China's Ministry of Science and Technology and the Ministry of Research, Science and Technology of New Zealand.

The monitoring system was deployed in October by researchers at the Nanjing Institute of Geology and Limnology, Chinese Academy of Scientists and the University of Waikato, New Zealand.

It is working well and capable of detecting potential outbreaks of blue-green algae, Qin Boqiang, a researcher at the Nanjing institute said. He is director of its water ecosystem laboratory in Wuxi and Suzhou.

"Before anything goes wrong, we can divert water from the Yangtze into the lake," he said.

"Before the system, we had to build a platform to physically get water samples. It was dangerous and expensive, so we could not do it frequently, especially not at night or during high winds."

The lake requires at least 15 monitoring systems, Zhu Guangwei, a researcher at the Nanjing institute, said.

Four systems will be deployed at the end of this year, and others by the end of 2010. The total cost will be about 40 million yuan (US$5.7 million).

Scientists cannot decide if there has been a considerable reduction in the factors that caused the algae, Chris McBridge, member of the New Zealand university that designed the system, said.

"It is too early to say if there have been any remarkable changes," he said.

(Xinhua News Agency April 18, 2008)