FN Archimer Export Format
PT J
TI Anammox bacteria drive fixed nitrogen loss in hadal trench sediments
BT 
AF Thamdrup, Bo
   Schauberger, Clemens
   Larsen, Morten
   TROUCHE, Blandine
   Maignien, Lois
   Arnaud-Haond, Sophie
   Wenzhöfer, Frank
   Glud, Ronnie N.
AS 1:1;2:1;3:1;4:2;5:2;6:3;7:1,4,5;8:1,6,7;
FF 1:;2:;3:;4:;5:;6:PDG-RBE-MARBEC-LHM;7:;8:;
C1 Nordcee and HADAL, Department of Biology, University of Southern Denmark 5230 Odense M, Denmar
   Microbiology of Extreme Environments Laboratory, CNRS, Institut Français de Recherche pour L'Exploitation de la Mer, University of Brest, 29280 Plouzané, France
   MARBEC, Université Montpellier, Institut Français de Recherche pour L'Exploitation de la Mer, CNRS, Institut de recherche pour le développement, 34203 Sète, France
   HGF-MPG Group for Deep Sea Ecology and Technology, Alfred Wegener Institute Helmholtz Center for Polar and Marine Research 27570 Bremerhaven, Germany
   HGF-MPG Group for Deep Sea Ecology and Technology, Max Planck Institute for Marine Microbiology, Bremen 28357, Germany
   Department of Ocean and Environmental Sciences, Tokyo University of Marine Science and Technology, Tokyo 108-8477, Japan
   Danish Institute of Advanced Study, University of Southern Denmark, 5230 Odense M, Denmark
C2 UNIV SOUTHERN DENMARK, DENMARK
   UBO, FRANCE
   IFREMER, FRANCE
   INST A WEGENER, GERMANY
   INST MAX PLANCK (MARINE MICROBIOL), GERMANY
   UNIV TOKYO, JAPAN
   UNIV SOUTHERN DENMARK, DENMARK
SI BREST
   SETE
SE PDG-REM-EEP-LMEE
   PDG-RBE-MARBEC-LHM
UM BEEP-LM2E
   MARBEC
IN WOS Ifremer UMR
   WOS Cotutelle UMR
   copubli-france
   copubli-europe
   copubli-univ-france
   copubli-int-hors-europe
IF 12.779
TC 17
UR https://archimer.ifremer.fr/doc/00736/84808/89846.pdf
   https://archimer.ifremer.fr/doc/00736/84808/89847.pdf
LA English
DT Article
DE ;hadal trenches;marine biogeochemistry;microbial ecology;denitrification
AB Benthic N2 production by microbial denitrification and anammox is the largest sink for fixed nitrogen in the oceans. Most N2 production occurs on the continental shelves, where a high flux of reactive organic matter fuels the depletion of nitrate close to the sediment surface. By contrast, N2 production rates in abyssal sediments are low due to low inputs of reactive organics, and nitrogen transformations are dominated by aerobic nitrification and the release of nitrate to the bottom water. Here, we demonstrate that this trend is reversed in the deepest parts of the oceans, the hadal trenches, where focusing of reactive organic matter enhances benthic microbial activity. Thus, at ∼8-km depth in the Atacama Trench, underlying productive surface waters, nitrate is depleted within a few centimeters of the sediment surface, N2 production rates reach those reported from some continental margin sites, and fixed nitrogen loss is mainly conveyed by anammox bacteria. These bacteria are closely related to those known from shallow oxygen minimum zone waters, and comparison of activities measured in the laboratory and in situ suggest they are piezotolerant. Even the Kermadec Trench, underlying oligotrophic surface waters, exhibits substantial fixed N removal. Our results underline the role of hadal sediments as hot spots of deep-sea biological activity, revealing a fully functional benthic nitrogen cycle at high hydrostatic pressure and pointing to hadal sediments as a previously unexplored niche for anaerobic microbial ecology and diagenesis. 
PY 2021
PD NOV
SO Proceedings Of The National Academy Of Sciences Of The United States Of America
SN 0027-8424
PU Proceedings of the National Academy of Sciences
VL 118
IS 46
UT 000723038500005
DI 10.1073/pnas.2104529118
ID 84808
ER

EF