Aerobic Microbial Respiration In Oceanic Oxygen Minimum Zones.

Kalvelage, Tim, Lavik, Gaute, Jensen, Marlene M., Revsbech, Niels Peter, Löscher, Carolin, Schunck, Harald, Desai, Dhwani, Hauss, Helena , Kiko, Rainer , Holtappels, Moritz, LaRoche, Julie, Schmitz, Ruth , Graco, Michelle I. and Kuypers, Marcel M. M. (2015) Aerobic Microbial Respiration In Oceanic Oxygen Minimum Zones. Open Access PLoS ONE, 10 (7). e0133526. DOI 10.1371/journal.pone.0133526.

[img]
Preview
Text
journal.pone.0133526.pdf - Published Version
Available under License Creative Commons: Attribution 3.0.

Download (2349Kb) | Preview

Supplementary data:

Abstract

Oxygen minimum zones are major sites of fixed nitrogen loss in the ocean. Recent studies have highlighted the importance of anaerobic ammonium oxidation, anammox, in pelagic nitrogen removal. Sources of ammonium for the anammox reaction, however, remain controversial, as heterotrophic denitrification and alternative anaerobic pathways of organic matter remineralization cannot account for the ammonium requirements of reported anammox rates. Here, we explore the significance of microaerobic respiration as a source of ammonium during organic matter degradation in the oxygen-deficient waters off Namibia and Peru. Experiments with additions of double-labelled oxygen revealed high aerobic activity in the upper OMZs, likely controlled by surface organic matter export. Consistently observed oxygen consumption in samples retrieved throughout the lower OMZs hints at efficient exploitation of vertically and laterally advected, oxygenated waters in this zone by aerobic microorganisms. In accordance, metagenomic and metatranscriptomic analyses identified genes encoding for aerobic terminal oxidases and demonstrated their expression by diverse microbial communities, even in virtually anoxic waters. Our results suggest that microaerobic respiration is a major mode of organic matter remineralization and source of ammonium (~45-100%) in the upper oxygen minimum zones, and reconcile hitherto observed mismatches between ammonium producing and consuming processes therein.

Document Type: Article
Keywords: Oceanic oxygen minimum zones ; Aerobic microbial respiration
Research affiliation: OceanRep > SFB 754
OceanRep > GEOMAR > FB3 Marine Ecology > FB3-EOE-N Experimental Ecology - Food Webs
OceanRep > GEOMAR > FB2 Marine Biogeochemistry > FB2-BI Biological Oceanography
OceanRep > GEOMAR > FB3 Marine Ecology > FB3-EOE-B Experimental Ecology - Benthic Ecology
Refereed: Yes
Open Access Journal?: Yes
DOI etc.: 10.1371/journal.pone.0133526
ISSN: 1932-6203
Projects: SFB754, Future Ocean
Date Deposited: 22 Jul 2015 09:56
Last Modified: 23 Sep 2019 22:21
URI: http://oceanrep.geomar.de/id/eprint/29287

Actions (login required)

View Item View Item

Document Downloads

More statistics for this item...