Plastic pollution fosters more microbial growth in lakes than natural organic matter


Type
Article
Change log
Authors
Sheridan, Eleanor A  ORCID logo  https://orcid.org/0000-0001-7358-7816
Fonvielle, Jérémy A  ORCID logo  https://orcid.org/0000-0002-8077-2419
Cottingham, Samuel 
Zhang, Yi 
Abstract

Plastic debris widely pollutes freshwaters. Abiotic and biotic degradation of plastics releases carbon-based substrates that are available for heterotrophic growth, but little is known about how these novel organic compounds influence microbial metabolism. Here we found leachate from plastic shopping bags was chemically distinct and more bioavailable than natural organic matter from 29 Scandinavian lakes. Consequently, plastic leachate increased bacterial biomass acquisition by 2.29-times when added at an environmentally-relevant concentration to lake surface waters. These results were not solely attributable to the amount of dissolved organic carbon provided by the leachate. Bacterial growth was 1.72-times more efficient with plastic leachate because the added carbon was more accessible than natural organic matter. These effects varied with both the availability of alternate, especially labile, carbon sources and bacterial diversity. Together, our results suggest that plastic pollution may stimulate aquatic food webs and highlight where pollution mitigation strategies could be most effective.

Description
Keywords
Bacteria, Carbon, Environmental Pollution, Heterotrophic Processes, Lakes, Plastics
Journal Title
Nature Communications
Conference Name
Journal ISSN
2041-1723
2041-1723
Volume Title
13
Publisher
Nature Research
Sponsorship
European Research Council (804673)
Funded by ERC Starting Grant 804673 to AJT