Sediment and pore water geochemistry of sediment cores, Potter Cove, King George Island
Redox-sensitive trace metals (Mn, Fe, U, Mo, Re), nutrients and terminal metabolic products (NO3-, NH4+, PO43-, total alkalinity) were for the first time investigated in pore waters of Antarctic coastal sediments. The results of this study reveal a high spatial variability in redox conditions in sur...
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ftpangaea:oai:pangaea.de:doi:10.1594/PANGAEA.832335 2023-05-15T13:42:11+02:00 Sediment and pore water geochemistry of sediment cores, Potter Cove, King George Island Monien, Patrick Lettmann, Karsten Alexander Monien, Donata Asendorf, Sanja Wölfl, Anne-Cathrin Lim, Chai Heng Thal, Janis Schnetger, Bernhard Brumsack, Hans-Jürgen MEDIAN LATITUDE: -62.230540 * MEDIAN LONGITUDE: -58.664655 * SOUTH-BOUND LATITUDE: -62.245529 * WEST-BOUND LONGITUDE: -58.702625 * NORTH-BOUND LATITUDE: -62.221619 * EAST-BOUND LONGITUDE: -58.639113 * DATE/TIME START: 2010-01-21T18:00:00 * DATE/TIME END: 2011-02-10T15:30:00 2014-05-06 application/zip, 60 datasets https://doi.pangaea.de/10.1594/PANGAEA.832335 https://doi.org/10.1594/PANGAEA.832335 en eng PANGAEA https://doi.pangaea.de/10.1594/PANGAEA.832335 https://doi.org/10.1594/PANGAEA.832335 CC-BY-3.0: Creative Commons Attribution 3.0 Unported Access constraints: unrestricted info:eu-repo/semantics/openAccess CC-BY Supplement to: Monien, Patrick; Lettmann, Karsten Alexander; Monien, Donata; Asendorf, Sanja; Wölfl, Anne-Cathrin; Lim, Chai Heng; Thal, Janis; Schnetger, Bernhard; Brumsack, Hans-Jürgen (2014): Redox conditions and trace metal cycling in coastal sediments from the maritime Antarctic. Geochimica et Cosmochimica Acta, 141, 26-44, https://doi.org/10.1016/j.gca.2014.06.003 IMCOAST/IMCONet Impact of climate induced glacier melt on marine coastal systems Antarctica Dataset 2014 ftpangaea https://doi.org/10.1594/PANGAEA.832335 https://doi.org/10.1016/j.gca.2014.06.003 2023-01-20T07:33:17Z Redox-sensitive trace metals (Mn, Fe, U, Mo, Re), nutrients and terminal metabolic products (NO3-, NH4+, PO43-, total alkalinity) were for the first time investigated in pore waters of Antarctic coastal sediments. The results of this study reveal a high spatial variability in redox conditions in surface sediments from Potter Cove, King George Island, western Antarctic Peninsula. Particularly in the shallower areas of the bay the significant correlation between sulphate depletion and total alkalinity, the inorganic product of terminal metabolism, indicates sulphate reduction to be the major pathway of organic matter mineralisation. In contrast, dissimilatory metal oxide reduction seems to be prevailing in the newly ice-free areas and the deeper troughs, where concentrations of dissolved iron of up to 700 µM were found. We suggest that the increased accumulation of fine-grained material with high amounts of reducible metal oxides in combination with the reduced availability of metabolisable organic matter and enhanced physical and biological disturbance by bottom water currents, ice scouring and burrowing organisms favours metal oxide reduction over sulphate reduction in these areas. Based on modelled iron fluxes we calculate the contribution of the Antarctic shelf to the pool of potentially bioavailable iron (Feb) to be 6.9x10**3 to 790x10**3 t/yr. Consequently, these shelf sediments would provide an Feb flux of 0.35-39.5/mg/m**2/yr (median: 3.8 mg/m**2/yr) to the Southern Ocean. This contribution is in the same order of magnitude as the flux provided by icebergs and significantly higher than the input by aeolian dust. For this reason suboxic shelf sediments form a key source of iron for the high nutrient-low chlorophyll (HNLC) areas of the Southern Ocean. This source may become even more important in the future due to rising temperatures at the WAP accompanied by enhanced glacier retreat and the accumulation of melt water derived iron-rich material on the shelf. Dataset Antarc* Antarctic Antarctic Peninsula Antarctica Iceberg* King George Island Southern Ocean PANGAEA - Data Publisher for Earth & Environmental Science Antarctic Southern Ocean The Antarctic Antarctic Peninsula King George Island Potter Cove ENVELOPE(-58.702625,-58.639113,-62.221619,-62.245529) |
institution |
Open Polar |
collection |
PANGAEA - Data Publisher for Earth & Environmental Science |
op_collection_id |
ftpangaea |
language |
English |
topic |
IMCOAST/IMCONet Impact of climate induced glacier melt on marine coastal systems Antarctica |
spellingShingle |
IMCOAST/IMCONet Impact of climate induced glacier melt on marine coastal systems Antarctica Monien, Patrick Lettmann, Karsten Alexander Monien, Donata Asendorf, Sanja Wölfl, Anne-Cathrin Lim, Chai Heng Thal, Janis Schnetger, Bernhard Brumsack, Hans-Jürgen Sediment and pore water geochemistry of sediment cores, Potter Cove, King George Island |
topic_facet |
IMCOAST/IMCONet Impact of climate induced glacier melt on marine coastal systems Antarctica |
description |
Redox-sensitive trace metals (Mn, Fe, U, Mo, Re), nutrients and terminal metabolic products (NO3-, NH4+, PO43-, total alkalinity) were for the first time investigated in pore waters of Antarctic coastal sediments. The results of this study reveal a high spatial variability in redox conditions in surface sediments from Potter Cove, King George Island, western Antarctic Peninsula. Particularly in the shallower areas of the bay the significant correlation between sulphate depletion and total alkalinity, the inorganic product of terminal metabolism, indicates sulphate reduction to be the major pathway of organic matter mineralisation. In contrast, dissimilatory metal oxide reduction seems to be prevailing in the newly ice-free areas and the deeper troughs, where concentrations of dissolved iron of up to 700 µM were found. We suggest that the increased accumulation of fine-grained material with high amounts of reducible metal oxides in combination with the reduced availability of metabolisable organic matter and enhanced physical and biological disturbance by bottom water currents, ice scouring and burrowing organisms favours metal oxide reduction over sulphate reduction in these areas. Based on modelled iron fluxes we calculate the contribution of the Antarctic shelf to the pool of potentially bioavailable iron (Feb) to be 6.9x10**3 to 790x10**3 t/yr. Consequently, these shelf sediments would provide an Feb flux of 0.35-39.5/mg/m**2/yr (median: 3.8 mg/m**2/yr) to the Southern Ocean. This contribution is in the same order of magnitude as the flux provided by icebergs and significantly higher than the input by aeolian dust. For this reason suboxic shelf sediments form a key source of iron for the high nutrient-low chlorophyll (HNLC) areas of the Southern Ocean. This source may become even more important in the future due to rising temperatures at the WAP accompanied by enhanced glacier retreat and the accumulation of melt water derived iron-rich material on the shelf. |
format |
Dataset |
author |
Monien, Patrick Lettmann, Karsten Alexander Monien, Donata Asendorf, Sanja Wölfl, Anne-Cathrin Lim, Chai Heng Thal, Janis Schnetger, Bernhard Brumsack, Hans-Jürgen |
author_facet |
Monien, Patrick Lettmann, Karsten Alexander Monien, Donata Asendorf, Sanja Wölfl, Anne-Cathrin Lim, Chai Heng Thal, Janis Schnetger, Bernhard Brumsack, Hans-Jürgen |
author_sort |
Monien, Patrick |
title |
Sediment and pore water geochemistry of sediment cores, Potter Cove, King George Island |
title_short |
Sediment and pore water geochemistry of sediment cores, Potter Cove, King George Island |
title_full |
Sediment and pore water geochemistry of sediment cores, Potter Cove, King George Island |
title_fullStr |
Sediment and pore water geochemistry of sediment cores, Potter Cove, King George Island |
title_full_unstemmed |
Sediment and pore water geochemistry of sediment cores, Potter Cove, King George Island |
title_sort |
sediment and pore water geochemistry of sediment cores, potter cove, king george island |
publisher |
PANGAEA |
publishDate |
2014 |
url |
https://doi.pangaea.de/10.1594/PANGAEA.832335 https://doi.org/10.1594/PANGAEA.832335 |
op_coverage |
MEDIAN LATITUDE: -62.230540 * MEDIAN LONGITUDE: -58.664655 * SOUTH-BOUND LATITUDE: -62.245529 * WEST-BOUND LONGITUDE: -58.702625 * NORTH-BOUND LATITUDE: -62.221619 * EAST-BOUND LONGITUDE: -58.639113 * DATE/TIME START: 2010-01-21T18:00:00 * DATE/TIME END: 2011-02-10T15:30:00 |
long_lat |
ENVELOPE(-58.702625,-58.639113,-62.221619,-62.245529) |
geographic |
Antarctic Southern Ocean The Antarctic Antarctic Peninsula King George Island Potter Cove |
geographic_facet |
Antarctic Southern Ocean The Antarctic Antarctic Peninsula King George Island Potter Cove |
genre |
Antarc* Antarctic Antarctic Peninsula Antarctica Iceberg* King George Island Southern Ocean |
genre_facet |
Antarc* Antarctic Antarctic Peninsula Antarctica Iceberg* King George Island Southern Ocean |
op_source |
Supplement to: Monien, Patrick; Lettmann, Karsten Alexander; Monien, Donata; Asendorf, Sanja; Wölfl, Anne-Cathrin; Lim, Chai Heng; Thal, Janis; Schnetger, Bernhard; Brumsack, Hans-Jürgen (2014): Redox conditions and trace metal cycling in coastal sediments from the maritime Antarctic. Geochimica et Cosmochimica Acta, 141, 26-44, https://doi.org/10.1016/j.gca.2014.06.003 |
op_relation |
https://doi.pangaea.de/10.1594/PANGAEA.832335 https://doi.org/10.1594/PANGAEA.832335 |
op_rights |
CC-BY-3.0: Creative Commons Attribution 3.0 Unported Access constraints: unrestricted info:eu-repo/semantics/openAccess |
op_rightsnorm |
CC-BY |
op_doi |
https://doi.org/10.1594/PANGAEA.832335 https://doi.org/10.1016/j.gca.2014.06.003 |
_version_ |
1766164618398400512 |