Sulfate reduction and methane oxidation activity below the sulfate-methane transition zone in Alaskan Beaufort Sea continental margin sediments: Implications for deep sulfur cycling
Two ∼6 m long sediment cores were collected along the ∼300 m isobath on the Alaskan Beaufort Sea continental margin. Both cores showed distinct sulfate-methane transition zones (SMTZ) at 105 and 120 cm below seafloor (cmbsf). Sulfate was not completely depleted below the SMTZ but remained between 30...
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ftoceanrep:oai:oceanrep.geomar.de:25856 2023-05-15T15:40:17+02:00 Sulfate reduction and methane oxidation activity below the sulfate-methane transition zone in Alaskan Beaufort Sea continental margin sediments: Implications for deep sulfur cycling Treude, Tina Krause, Stefan Maltby, Johanna Dale, Andrew W. Coffin, Richard Hamdan, Leila J. 2014-09-01 text https://oceanrep.geomar.de/id/eprint/25856/ https://oceanrep.geomar.de/id/eprint/25856/1/Treude_et_al.2014_GCA.pdf https://doi.org/10.1016/j.gca.2014.08.018 en eng Elsevier https://oceanrep.geomar.de/id/eprint/25856/1/Treude_et_al.2014_GCA.pdf Treude, T. , Krause, S., Maltby, J., Dale, A. W. , Coffin, R. and Hamdan, L. J. (2014) Sulfate reduction and methane oxidation activity below the sulfate-methane transition zone in Alaskan Beaufort Sea continental margin sediments: Implications for deep sulfur cycling. Geochimica et Cosmochimica Acta, 144 . pp. 217-237. DOI 10.1016/j.gca.2014.08.018 <https://doi.org/10.1016/j.gca.2014.08.018>. doi:10.1016/j.gca.2014.08.018 info:eu-repo/semantics/restrictedAccess Article PeerReviewed 2014 ftoceanrep https://doi.org/10.1016/j.gca.2014.08.018 2023-04-07T15:14:53Z Two ∼6 m long sediment cores were collected along the ∼300 m isobath on the Alaskan Beaufort Sea continental margin. Both cores showed distinct sulfate-methane transition zones (SMTZ) at 105 and 120 cm below seafloor (cmbsf). Sulfate was not completely depleted below the SMTZ but remained between 30 and 500 μM. Sulfate reduction and anaerobic oxidation of methane (AOM) determined by radiotracer incubations were active throughout the methanogenic zone. Although a mass balance could not explain the source of sulfate below the SMTZ, geochemical profiles and correlation network analyses of biotic and abiotic data suggest a cryptic sulfur cycle involving iron, manganese and barite. Inhibition experiments with molybdate and 2-bromoethanesulfonate (BES) indicated decoupling of sulfate reduction and AOM and competition between sulfate reducers and methanogens for substrates. While correlation network analyses predicted coupling of AOM to iron reduction, the addition of manganese or iron did not stimulate AOM. Since none of the classical archaeal anaerobic methanotrophs (ANME) were abundant, the involvement of unknown or unconventional phylotypes in AOM is conceivable. The resistance of AOM activity to inhibitors implies deviation from conventional enzymatic pathways. This work suggests that the classical redox cascade of electron acceptor utilization based on Gibbs energy yields does not always hold in diffusion-dominated systems, and instead biotic processes may be more strongly coupled to mineralogy. Article in Journal/Newspaper Beaufort Sea OceanRep (GEOMAR Helmholtz Centre für Ocean Research Kiel) Geochimica et Cosmochimica Acta 144 217 237 |
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Open Polar |
collection |
OceanRep (GEOMAR Helmholtz Centre für Ocean Research Kiel) |
op_collection_id |
ftoceanrep |
language |
English |
description |
Two ∼6 m long sediment cores were collected along the ∼300 m isobath on the Alaskan Beaufort Sea continental margin. Both cores showed distinct sulfate-methane transition zones (SMTZ) at 105 and 120 cm below seafloor (cmbsf). Sulfate was not completely depleted below the SMTZ but remained between 30 and 500 μM. Sulfate reduction and anaerobic oxidation of methane (AOM) determined by radiotracer incubations were active throughout the methanogenic zone. Although a mass balance could not explain the source of sulfate below the SMTZ, geochemical profiles and correlation network analyses of biotic and abiotic data suggest a cryptic sulfur cycle involving iron, manganese and barite. Inhibition experiments with molybdate and 2-bromoethanesulfonate (BES) indicated decoupling of sulfate reduction and AOM and competition between sulfate reducers and methanogens for substrates. While correlation network analyses predicted coupling of AOM to iron reduction, the addition of manganese or iron did not stimulate AOM. Since none of the classical archaeal anaerobic methanotrophs (ANME) were abundant, the involvement of unknown or unconventional phylotypes in AOM is conceivable. The resistance of AOM activity to inhibitors implies deviation from conventional enzymatic pathways. This work suggests that the classical redox cascade of electron acceptor utilization based on Gibbs energy yields does not always hold in diffusion-dominated systems, and instead biotic processes may be more strongly coupled to mineralogy. |
format |
Article in Journal/Newspaper |
author |
Treude, Tina Krause, Stefan Maltby, Johanna Dale, Andrew W. Coffin, Richard Hamdan, Leila J. |
spellingShingle |
Treude, Tina Krause, Stefan Maltby, Johanna Dale, Andrew W. Coffin, Richard Hamdan, Leila J. Sulfate reduction and methane oxidation activity below the sulfate-methane transition zone in Alaskan Beaufort Sea continental margin sediments: Implications for deep sulfur cycling |
author_facet |
Treude, Tina Krause, Stefan Maltby, Johanna Dale, Andrew W. Coffin, Richard Hamdan, Leila J. |
author_sort |
Treude, Tina |
title |
Sulfate reduction and methane oxidation activity below the sulfate-methane transition zone in Alaskan Beaufort Sea continental margin sediments: Implications for deep sulfur cycling |
title_short |
Sulfate reduction and methane oxidation activity below the sulfate-methane transition zone in Alaskan Beaufort Sea continental margin sediments: Implications for deep sulfur cycling |
title_full |
Sulfate reduction and methane oxidation activity below the sulfate-methane transition zone in Alaskan Beaufort Sea continental margin sediments: Implications for deep sulfur cycling |
title_fullStr |
Sulfate reduction and methane oxidation activity below the sulfate-methane transition zone in Alaskan Beaufort Sea continental margin sediments: Implications for deep sulfur cycling |
title_full_unstemmed |
Sulfate reduction and methane oxidation activity below the sulfate-methane transition zone in Alaskan Beaufort Sea continental margin sediments: Implications for deep sulfur cycling |
title_sort |
sulfate reduction and methane oxidation activity below the sulfate-methane transition zone in alaskan beaufort sea continental margin sediments: implications for deep sulfur cycling |
publisher |
Elsevier |
publishDate |
2014 |
url |
https://oceanrep.geomar.de/id/eprint/25856/ https://oceanrep.geomar.de/id/eprint/25856/1/Treude_et_al.2014_GCA.pdf https://doi.org/10.1016/j.gca.2014.08.018 |
genre |
Beaufort Sea |
genre_facet |
Beaufort Sea |
op_relation |
https://oceanrep.geomar.de/id/eprint/25856/1/Treude_et_al.2014_GCA.pdf Treude, T. , Krause, S., Maltby, J., Dale, A. W. , Coffin, R. and Hamdan, L. J. (2014) Sulfate reduction and methane oxidation activity below the sulfate-methane transition zone in Alaskan Beaufort Sea continental margin sediments: Implications for deep sulfur cycling. Geochimica et Cosmochimica Acta, 144 . pp. 217-237. DOI 10.1016/j.gca.2014.08.018 <https://doi.org/10.1016/j.gca.2014.08.018>. doi:10.1016/j.gca.2014.08.018 |
op_rights |
info:eu-repo/semantics/restrictedAccess |
op_doi |
https://doi.org/10.1016/j.gca.2014.08.018 |
container_title |
Geochimica et Cosmochimica Acta |
container_volume |
144 |
container_start_page |
217 |
op_container_end_page |
237 |
_version_ |
1766372467970932736 |