News: Big Impact, Research, WA

Impact of ocean plastics

Microscopic creatures that live on tiny ocean plastics greatly affect the fate and ecological impacts of that plastic. PhD student Julia Reisser from the University of Western Australia has published her research on the microbes and invertebrates living on sand-sized marine plastic fragments. Her supervisor, Prof. Chari Pattiaratchi, said that there were huge numbers of floating plastics at sea and the study was the first to document biological communities on this floating pollution in Australian waters. The tiny ocean plastics come from the breakdown of discarded plastic items, such as single-use packaging and fishing gear.

More than 1000 scanning electron microscope images were taken at the AMMRF at UWA while examining ocean plastics from Australia-wide sample collections. They tell an interesting story with both negative and positive aspects. The bad news is that organisms growing on the plastic could make ocean plastics more attractive as food for animals, inducing plastic ingestion. Furthermore, species living on ocean plastic could disperse more widely across oceans than they could on their own, potentially invading new habitats and impacting local ecosystems.

On the other hand some silica-forming algae can weigh down the plastic fragments and cause them to sink to the bottom of the ocean decreasing plastic pollution at the sea surface, where major environmental impacts occur. The researchers were also able to see colonies of microbes that seem to be ’eating’ the plastics. Ms Reisser said. “Plastic biodegradation seems to happen at sea. I am excited about this because the ‘plastic-eating’ microbes could provide solutions for better waste disposal practices on land.â€?

June 20, 2014