Dataset Information

Ecological control of nitrite in the upper ocean.

ABSTRACT: Microorganisms oxidize organic nitrogen to nitrate in a series of steps. Nitrite, an intermediate product, accumulates at the base of the sunlit layer in the subtropical ocean, forming a primary nitrite maximum, but can accumulate throughout the sunlit layer at higher latitudes. We model nitrifying chemoautotrophs in a marine ecosystem and demonstrate that microbial community interactions can explain the nitrite distributions. Our theoretical framework proposes that nitrite can accumulate to a higher concentration than ammonium because of differences in underlying redox chemistry and cell size between ammonia- and nitrite-oxidizing chemoautotrophs. Using ocean circulation models, we demonstrate that nitrifying microorganisms are excluded in the sunlit layer when phytoplankton are nitrogen-limited, but thrive at depth when phytoplankton become light-limited, resulting in nitrite accumulation there. However, nitrifying microorganisms may coexist in the sunlit layer when phytoplankton are iron- or light-limited (often in higher latitudes). These results improve understanding of the controls on nitrification, and provide a framework for representing chemoautotrophs and their biogeochemical effects in ocean models.

SUBMITTER: Zakem EJ

PROVIDER: S-EPMC5865239 | biostudies-literature | 2018 Mar

REPOSITORIES: biostudies-literature

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Ecological control of nitrite in the upper ocean.

Zakem Emily J EJ Al-Haj Alia A Church Matthew J MJ van Dijken Gert L GL Dutkiewicz Stephanie S Foster Sarah Q SQ Fulweiler Robinson W RW Mills Matthew M MM Follows Michael J MJ

Nature communications 20180323 1

Microorganisms oxidize organic nitrogen to nitrate in a series of steps. Nitrite, an intermediate product, accumulates at the base of the sunlit layer in the subtropical ocean, forming a primary nitrite maximum, but can accumulate throughout the sunlit layer at higher latitudes. We model nitrifying chemoautotrophs in a marine ecosystem and demonstrate that microbial community interactions can explain the nitrite distributions. Our theoretical framework proposes that nitrite can accumulate to a h ...[more]

PMID: 29572474

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Dataset Information

Ecological control of nitrite in the upper ocean.

Publications

Ecological control of nitrite in the upper ocean.

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