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Microplastics affect sedimentary microbial communities and nitrogen cycling.

ABSTRACT: Microplastics are ubiquitous in estuarine, coastal, and deep sea sediments. The impacts of microplastics on sedimentary microbial ecosystems and biogeochemical carbon and nitrogen cycles, however, have not been well reported. To evaluate if microplastics influence the composition and function of sedimentary microbial communities, we conducted a microcosm experiment using salt marsh sediment amended with polyethylene (PE), polyvinyl chloride (PVC), polyurethane foam (PUF) or polylactic acid (PLA) microplastics. We report that the presence of microplastics alters sediment microbial community composition and nitrogen cycling processes. Compared to control sediments without microplastic, PUF- and PLA-amended sediments promote nitrification and denitrification, while PVC amendment inhibits both processes. These results indicate that nitrogen cycling processes in sediments can be significantly affected by different microplastics, which may serve as organic carbon substrates for microbial communities. Considering this evidence and increasing microplastic pollution, the impact of plastics on global ecosystems and biogeochemical cycling merits critical investigation.

SUBMITTER: Seeley ME

PROVIDER: S-EPMC7217880 | biostudies-literature | 2020 May

REPOSITORIES: biostudies-literature

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Microplastics affect sedimentary microbial communities and nitrogen cycling.

Seeley Meredith E ME Song Bongkeun B Passie Renia R Hale Robert C RC

Nature communications 20200512 1

Microplastics are ubiquitous in estuarine, coastal, and deep sea sediments. The impacts of microplastics on sedimentary microbial ecosystems and biogeochemical carbon and nitrogen cycles, however, have not been well reported. To evaluate if microplastics influence the composition and function of sedimentary microbial communities, we conducted a microcosm experiment using salt marsh sediment amended with polyethylene (PE), polyvinyl chloride (PVC), polyurethane foam (PUF) or polylactic acid (PLA) ...[more]

PMID: 32398678

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Microplastics affect sedimentary microbial communities and nitrogen cycling.

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Microplastics affect sedimentary microbial communities and nitrogen cycling.

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