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Blue water, green algae and dark threats - Acoustics outside the laboratory?

Philippe Blondel


Dr Philippe Blondel


Tuesday 17 November at 5.15pm


Room 3.15, Chancellors' Building, University of Bath (Location and maps)


Clean water is what we all want, from freshwater reservoirs to pipes, rivers and coastal ecosystems. But this can be threatened by algae. They can block pipes and reservoir inlets, affect natural water filtering, and even harm aquatic life through eutrophication. Algae large enough to see with the naked eye (macrophytes) can have positive sides, though, and they are increasingly used in the chemical, pharmaceutical and food industry. Kelps are the largest marine crop, with over 4 million tonnes harvested annually. As a source of ecosystem services and natural capital, macrophytes accounts for at least 11.4% of the worldwide value of all ecosystems. But algae are difficult to monitor regularly and accurately: they can be hidden from direct view (e.g. deep in large reservoirs or in water intake pipes), they can be few enough that they are not noticed in time (e.g. until warm weather or eutrophication) or they can be small enough that they are not easily detected (e.g. cyanobacteria). This is where acoustics can help, and this talk will present acoustic imaging in general, focusing on detecting and mapping algae in the field. Applications will be drawn from our own research and include kelp beds in British Columbia, and how they can be used by humans and grey whales, and algae in the Arctic, and how they evolve with glaciers melting and the dark threat of climate change.

Refreshments will be available from 4.45pm in Room 3.11, Chancellors' Building.