Chinese scientists clear blue-green algae bloom from massive lake with cheap ‘sterilisation’ boat
- Drone-guided boat uses water pressure to burst air pockets that give cyanobacteria their buoyancy, making them sink and eventually perish
- Lake Tai cleared of 80 per cent of explosive bloom, in a process the research team has likened to China’s former one-child policy
Scientists in China effectively tamed blooming algae in one of the country’s largest lakes this summer, using a new technology to “sterilise” it, the Ministry of Science and Technology’s official newspaper reported.
Lake Tai, China’s third largest freshwater lake, spans 2,250 sq km across Jiangsu and Zhejiang, the wealthiest and most densely populated provinces on the eastern coast.
It had been troubled for decades by an explosive growth of cyanobacteria, or blue-green algae, which thrived on the waste water dumped into the lake by the surrounding cities, factories and farms.
But a special boat developed by Cong Haibing, a professor at Yangzhou University’s College of Environmental Science and Engineering, was able to reduce the concentration of floating algae in Lake Tai by more than 80 per cent, the official Science and Technology Daily reported.
The drone-guided boat is able to approach an algae colony as soon as it appears on the lake surface and implement a “birth control” technique that requires no drugs or chemicals, Cong told the paper.
“In order to remain suspended on the water surface to receive light for growth and reproduction, cyanobacteria have evolved a tiny air pocket in their bodies to provide buoyancy,” the professor was quoted as saying.
The boat has equipment to crush those air pockets, causing the cyanobacteria to sink to the bottom of the lake and eventually perish.