Benthic silicon cycling in the Arctic Barents Sea: a reaction–transport model study
Over recent decades the highest rates of water column warming and sea ice loss across the Arctic Ocean have been observed in the Barents Sea. These physical changes have resulted in rapid ecosystem adjustments, manifesting as a northward migration of temperate phytoplankton species at the expense of...
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Copernicus Publications
2022
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ftnonlinearchiv:oai:noa.gwlb.de:cop_mods_00061946 2023-05-15T15:02:03+02:00 Benthic silicon cycling in the Arctic Barents Sea: a reaction–transport model study Ward, James P. J. Hendry, Katharine R. Arndt, Sandra Faust, Johan C. Freitas, Felipe S. Henley, Sian F. Krause, Jeffrey W. März, Christian Tessin, Allyson C. Airs, Ruth L. 2022-07 electronic https://doi.org/10.5194/bg-19-3445-2022 https://noa.gwlb.de/receive/cop_mods_00061946 https://noa.gwlb.de/servlets/MCRFileNodeServlet/cop_derivate_00061308/bg-19-3445-2022.pdf https://bg.copernicus.org/articles/19/3445/2022/bg-19-3445-2022.pdf eng eng Copernicus Publications Biogeosciences -- http://www.bibliothek.uni-regensburg.de/ezeit/?2158181 -- http://www.copernicus.org/EGU/bg/bg.html -- 1726-4189 https://doi.org/10.5194/bg-19-3445-2022 https://noa.gwlb.de/receive/cop_mods_00061946 https://noa.gwlb.de/servlets/MCRFileNodeServlet/cop_derivate_00061308/bg-19-3445-2022.pdf https://bg.copernicus.org/articles/19/3445/2022/bg-19-3445-2022.pdf https://creativecommons.org/licenses/by/4.0/ uneingeschränkt info:eu-repo/semantics/openAccess CC-BY article Verlagsveröffentlichung article Text doc-type:article 2022 ftnonlinearchiv https://doi.org/10.5194/bg-19-3445-2022 2022-07-31T23:11:44Z Over recent decades the highest rates of water column warming and sea ice loss across the Arctic Ocean have been observed in the Barents Sea. These physical changes have resulted in rapid ecosystem adjustments, manifesting as a northward migration of temperate phytoplankton species at the expense of silica-based diatoms. These changes will potentially alter the composition of phytodetritus deposited at the seafloor, which acts as a biogeochemical reactor and is pivotal in the recycling of key nutrients, such as silicon (Si). To appreciate the sensitivity of the Barents Sea benthic system to the observed changes in surface primary production, there is a need to better understand this benthic–pelagic coupling. Stable Si isotopic compositions of sediment pore waters and the solid phase from three stations in the Barents Sea reveal a coupling of the iron (Fe) and Si cycles, the contemporaneous dissolution of lithogenic silicate minerals (LSi) alongside biogenic silica (BSi), and the potential for the reprecipitation of dissolved silicic acid (DSi) as authigenic clay minerals (AuSi). However, as reaction rates cannot be quantified from observational data alone, a mechanistic understanding of which factors control these processes is missing. Here, we employ reaction–transport modelling together with observational data to disentangle the reaction pathways controlling the cycling of Si within the seafloor. Processes such as the dissolution of BSi are active on multiple timescales, ranging from weeks to hundreds of years, which we are able to examine through steady state and transient model runs. Steady state simulations show that 60 % to 98 % of the sediment pore water DSi pool may be sourced from the dissolution of LSi, while the isotopic composition is also strongly influenced by the desorption of Si from metal oxides, most likely Fe (oxyhydr)oxides (FeSi), as they reductively dissolve. Further, our model simulations indicate that between 2.9 % and 37 % of the DSi released into sediment pore waters is subsequently ... Article in Journal/Newspaper Arctic Arctic Ocean Barents Sea Phytoplankton Sea ice Niedersächsisches Online-Archiv NOA Arctic Arctic Ocean Barents Sea Biogeosciences 19 14 3445 3467 |
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Niedersächsisches Online-Archiv NOA |
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ftnonlinearchiv |
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English |
topic |
article Verlagsveröffentlichung |
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article Verlagsveröffentlichung Ward, James P. J. Hendry, Katharine R. Arndt, Sandra Faust, Johan C. Freitas, Felipe S. Henley, Sian F. Krause, Jeffrey W. März, Christian Tessin, Allyson C. Airs, Ruth L. Benthic silicon cycling in the Arctic Barents Sea: a reaction–transport model study |
topic_facet |
article Verlagsveröffentlichung |
description |
Over recent decades the highest rates of water column warming and sea ice loss across the Arctic Ocean have been observed in the Barents Sea. These physical changes have resulted in rapid ecosystem adjustments, manifesting as a northward migration of temperate phytoplankton species at the expense of silica-based diatoms. These changes will potentially alter the composition of phytodetritus deposited at the seafloor, which acts as a biogeochemical reactor and is pivotal in the recycling of key nutrients, such as silicon (Si). To appreciate the sensitivity of the Barents Sea benthic system to the observed changes in surface primary production, there is a need to better understand this benthic–pelagic coupling. Stable Si isotopic compositions of sediment pore waters and the solid phase from three stations in the Barents Sea reveal a coupling of the iron (Fe) and Si cycles, the contemporaneous dissolution of lithogenic silicate minerals (LSi) alongside biogenic silica (BSi), and the potential for the reprecipitation of dissolved silicic acid (DSi) as authigenic clay minerals (AuSi). However, as reaction rates cannot be quantified from observational data alone, a mechanistic understanding of which factors control these processes is missing. Here, we employ reaction–transport modelling together with observational data to disentangle the reaction pathways controlling the cycling of Si within the seafloor. Processes such as the dissolution of BSi are active on multiple timescales, ranging from weeks to hundreds of years, which we are able to examine through steady state and transient model runs. Steady state simulations show that 60 % to 98 % of the sediment pore water DSi pool may be sourced from the dissolution of LSi, while the isotopic composition is also strongly influenced by the desorption of Si from metal oxides, most likely Fe (oxyhydr)oxides (FeSi), as they reductively dissolve. Further, our model simulations indicate that between 2.9 % and 37 % of the DSi released into sediment pore waters is subsequently ... |
format |
Article in Journal/Newspaper |
author |
Ward, James P. J. Hendry, Katharine R. Arndt, Sandra Faust, Johan C. Freitas, Felipe S. Henley, Sian F. Krause, Jeffrey W. März, Christian Tessin, Allyson C. Airs, Ruth L. |
author_facet |
Ward, James P. J. Hendry, Katharine R. Arndt, Sandra Faust, Johan C. Freitas, Felipe S. Henley, Sian F. Krause, Jeffrey W. März, Christian Tessin, Allyson C. Airs, Ruth L. |
author_sort |
Ward, James P. J. |
title |
Benthic silicon cycling in the Arctic Barents Sea: a reaction–transport model study |
title_short |
Benthic silicon cycling in the Arctic Barents Sea: a reaction–transport model study |
title_full |
Benthic silicon cycling in the Arctic Barents Sea: a reaction–transport model study |
title_fullStr |
Benthic silicon cycling in the Arctic Barents Sea: a reaction–transport model study |
title_full_unstemmed |
Benthic silicon cycling in the Arctic Barents Sea: a reaction–transport model study |
title_sort |
benthic silicon cycling in the arctic barents sea: a reaction–transport model study |
publisher |
Copernicus Publications |
publishDate |
2022 |
url |
https://doi.org/10.5194/bg-19-3445-2022 https://noa.gwlb.de/receive/cop_mods_00061946 https://noa.gwlb.de/servlets/MCRFileNodeServlet/cop_derivate_00061308/bg-19-3445-2022.pdf https://bg.copernicus.org/articles/19/3445/2022/bg-19-3445-2022.pdf |
geographic |
Arctic Arctic Ocean Barents Sea |
geographic_facet |
Arctic Arctic Ocean Barents Sea |
genre |
Arctic Arctic Ocean Barents Sea Phytoplankton Sea ice |
genre_facet |
Arctic Arctic Ocean Barents Sea Phytoplankton Sea ice |
op_relation |
Biogeosciences -- http://www.bibliothek.uni-regensburg.de/ezeit/?2158181 -- http://www.copernicus.org/EGU/bg/bg.html -- 1726-4189 https://doi.org/10.5194/bg-19-3445-2022 https://noa.gwlb.de/receive/cop_mods_00061946 https://noa.gwlb.de/servlets/MCRFileNodeServlet/cop_derivate_00061308/bg-19-3445-2022.pdf https://bg.copernicus.org/articles/19/3445/2022/bg-19-3445-2022.pdf |
op_rights |
https://creativecommons.org/licenses/by/4.0/ uneingeschränkt info:eu-repo/semantics/openAccess |
op_rightsnorm |
CC-BY |
op_doi |
https://doi.org/10.5194/bg-19-3445-2022 |
container_title |
Biogeosciences |
container_volume |
19 |
container_issue |
14 |
container_start_page |
3445 |
op_container_end_page |
3467 |
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1766334044479422464 |