Activity and abundance of denitrifying bacteria in the subsurface biosphere of diffuse hydrothermal vents of the Juan de Fuca Ridge
| dc.contributor.author | Bourbonnais, A. | |
| dc.contributor.author | Butterfield, D.A. | |
| dc.contributor.author | Chang, B.X. | |
| dc.contributor.author | Devol, A.H. | |
| dc.contributor.author | Hallam, S.J. | |
| dc.contributor.author | Juniper, S. Kim | |
| dc.contributor.author | Kuypers, M.M.M. | |
| dc.contributor.author | Lavik, G. | |
| dc.contributor.author | Lehmann, M.F. | |
| dc.contributor.author | Murdock, S.A. | |
| dc.contributor.author | Wenk, C.B. | |
| dc.date.accessioned | 2021-07-14T18:31:56Z | |
| dc.date.available | 2021-07-14T18:31:56Z | |
| dc.date.copyright | 2012 | en_US |
| dc.date.issued | 2012 | |
| dc.description.abstract | Little is known about fixed nitrogen (N) transformation and elimination at diffuse hydrothermal vents where anoxic fluids are mixed with oxygenated crustal seawater prior to discharge. Oceanic N sinks that remove bio-available N ultimately affect chemosynthetic primary productivity in these ecosystems. Using 15N paired isotope techniques, we determined potential rates of fixed N loss pathways (denitrification, anammox) and dissimilatory nitrate reduction to ammonium (DNRA) in sulfidic hydrothermal vent fluids discharging from the subsurface at several sites at Axial Volcano and the Endeavour Segment on the Juan de Fuca Ridge.We also measured physico-chemical parameters (i.e., temperature, pH, nutrients, H2S and N2O concentrations) as well as the biodiversity and abundance of chemolithoautotrophic nitrate-reducing, sulfur-oxidizing -proteobacteria (SUP05 cluster) using sequence analysis of amplified small subunit ribosomal RNA (16S rRNA) genes in combination with taxon-specific quantitative polymerase chain reaction (qPCR) assays. Denitrification was the dominant N loss pathway in the subsurface biosphere of the Juan de Fuca Ridge, with rates of up to 1000 nmolNl−1 day−1. In comparison, anammox rates were always <5 nmolNl−1 day−1 and below the detection limit at most of the sites. DNRA rates were up to 150 nmolNl−1 day−1. These results suggest that bacterial denitrification out-competes anammox in sulfidic hydrothermal vent waters. Taxon-specific qPCR revealed that -proteobacteria of the SUP05 cluster sometimes dominated the microbial community (SUP05/total bacteria up to 38 %). Significant correlations were found between fixed N loss (i.e., denitrification, anammox) rates and in situ nitrate and dissolved inorganic nitrogen (DIN) deficits in the fluids, indicating that DIN availability may ultimately regulate N loss in the subsurface. Based on our rate measurements, and on published data on hydrothermal fluid fluxes and residence times, we estimated that up to 10 TgNyr−1 could globally be removed in the subsurface biosphere of hydrothermal vents systems, thus, representing a small fraction of the total marine N loss ( 275 to >400 TgNyr−1). | en_US |
| dc.description.reviewstatus | Reviewed | en_US |
| dc.description.scholarlevel | Faculty | en_US |
| dc.description.sponsorship | This work was supported by the Natural Sciences and Engineering Research Council (NSERC) of Canada, the National Oceanographic and Atmospheric Administration (NOAA), the Max-Planck-Gesellschaft, the Canada Foundation for Innovation (CFI), and the Canadian Institute for Advanced Research (CIFAR). A. B. benefited from an NSERC graduate fellowship and a PEO Scholar Award. S. K. J. was funded by an NSERC Discovery grant, M. F. L. by NSERC Discovery and SNF (Swiss National Science Foundation) R’Equip grants, D. A. B. was supported by U. S. N. S. F. grant OCE 0731947 and the NOAA/PMEL Vents Programme (JISAO contribution number 2028, PMEL contribution number 3835), and S. H. was supported by CFI and CIFAR. We thank James Holden, Bill Chadwick, the officers and crew of the R/V Atlantis and R/V Thomas G. Thompson, and the ROPOS, Jason and Alvin submersible teams for exceptional field support, and Rika Anderson, Karina Giesbreck, Mark Haught, Alyse Hawley, Kevin Roe, R´eal Roy, Mark Rollog, Charles Stump, Elena Zaikova, and Jakob Zopfi for laboratory assistance. We also thank Julie Huber and Rika Anderson (John Baross’ lab, University of Washington) and Helene C. Ver Eecke (James Holden’s lab, University of Massachusetts) for sharing eDNA and bacterial count data, and Roberta Hamme for her help with denitrification rate measurements for the 2008 cruises. The CouchSurfing community provided accommodation for A. B. during sample analyses in Vancouver (Canada), Seattle (USA) and Bremen (Germany). Edited by: T. Treude | en_US |
| dc.identifier.citation | Bourbonnais, A., Butterfield, D.A., Chang, B.X., Devol, A.H., Hallam, S.J., Juniper, S.K., Kuypers, M.M.M., Lavik, G., Lehmann, M.F., Murdock, S.A., Wenk, C.B. (2012). Activity and abundance of denitrifying bacteria in the subsurface biosphere of diffuse hydrothermal vents of the Juan de Fuca Ridge. Biogeosciences, 9. https://doi.org/10.5194/bg-9-4661-2012 | en_US |
| dc.identifier.uri | https://doi.org/10.5194/bg-9-4661-2012 | |
| dc.identifier.uri | http://hdl.handle.net/1828/13116 | |
| dc.language.iso | en | en_US |
| dc.publisher | Biogeosciences | en_US |
| dc.title | Activity and abundance of denitrifying bacteria in the subsurface biosphere of diffuse hydrothermal vents of the Juan de Fuca Ridge | en_US |
| dc.type | Article | en_US |