Brussels, 30 Jan 2006
An experiment to assess the potential impact of climate change on the concentration of toxic algae in freshwater systems has been launched in the UK as part of a 20 million euro EU funded project.
Described by those carrying it out as the largest climate change experiment on freshwater systems in Europe to date, the research involves simulating freshwater systems containing the toxic blue-green algae (known as cyanobacteria) in 48 large heated water tanks, and measuring the effects of a 4 degree Celsius rise in temperature on the algae and its toxicity over time.
According to on of the researchers for the experiment, Heidrun Feuchtmayr from the University of Liverpool, 'There is limited knowledge about the impact of global climate change on freshwater systems. Many lakes in Europe have suffered problems with blue-green algae through the introduction of fertilisers, discharges from farms and organic chemicals such as washing powder into the water. We now need to look at how these problems may be exacerbated with an increase in temperature.'
There have been a number of well-documented cases of blue-green algae having negative effects on human health. In 1989, two soldiers were severely ill with atypical pneumonia following canoe training on an affected lake in Staffordshire, UK, while there is evidence that in Brazil in 1996 a number of patients on blood dialysis died after water containing blue-green algae was substituted for the normal water supply during a drought.
Dr Feuchtmayr told CORDIS News: 'Normally, if you were to approach [an affected] lake you would avoid drinking it or swimming in it due to the unpleasant colour and odour.' However, animals are often not so careful, and ingestion of toxic algae is reported to have caused the death of cattle, sheep, dogs and birds.
It is already known that a number of factors have an impact on the concentrations of algae in freshwater systems, such as wind and the presence of nutrients. Temperature might also have an effect, and according to Dr Feuchtmayr, 'Climate change is predicted to [lead to a rise in temperature of] three to five degrees Celsius in [...] parts of Europe in the next half century. We will investigate if blue-green algae blooms are more likely to form in heated water tanks and if the toxicity will increase with higher temperatures.'
The temperature of the 48 tanks is closely monitored through a series of sensors, with the data being fed into a computer which can precisely control the heat of the tanks, giving an increase of 4 degrees Celsius above ambient temperature in half of the tanks. 'At the beginning we try to establish similar conditions for all the tanks,' explains Dr Feuchtmayr, 'so that we can monitor changes in the foodweb, and sizes of organisms, adaptations to higher temperatures and other related aspects.'
The advantage of such a large scale experiment is that it offers the researchers the possibility of studying Community responses to the impacts of global warming. 'We are not in the laboratory - this is a big experiment outside and thus is closer to natural environmental conditions,' stressed Dr Feuchtmayr.
Whatever the results of the experiment, the data will feed in to the wider Euro-limpacs Integrated Project, of which it forms a part. The Euro-limpacs initiative was set up under the 'sustainable development, global change and ecosystems' priority of the Sixth Framework Programme (FP6), and involves 35 partners from 19 different countries, each evaluating the impacts of global change on different aspects of Europe's freshwater systems.