Seasonal and spatial dynamics of iron availability in the Scotia Sea
The Southern Ocean is the world's largest high nutrient low chlorophyll (HNLC) region. However, satellite images highlight several areas associated with island chains and shallow topographic features which display high phytoplankton biomass. Here we present the first study of seasonal variation...
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Online Access: | http://nora.nerc.ac.uk/id/eprint/17950/ http://www.sciencedirect.com/science/article/pii/S0304420311001320 |
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ftnerc:oai:nora.nerc.ac.uk:17950 2023-05-15T18:16:01+02:00 Seasonal and spatial dynamics of iron availability in the Scotia Sea Nielsdóttir, Maria C. Bibby, Thomas S. Moore, C. Mark Hinz, Daria J. Sanders, Richard Whitehouse, Michael Korb, Rebecca Achterberg, Eric P. 2012 http://nora.nerc.ac.uk/id/eprint/17950/ http://www.sciencedirect.com/science/article/pii/S0304420311001320 unknown Elsevier Nielsdóttir, Maria C.; Bibby, Thomas S.; Moore, C. Mark; Hinz, Daria J.; Sanders, Richard orcid:0000-0002-6884-7131 Whitehouse, Michael; Korb, Rebecca; Achterberg, Eric P. 2012 Seasonal and spatial dynamics of iron availability in the Scotia Sea. Marine Chemistry, 130-131. 62-72. https://doi.org/10.1016/j.marchem.2011.12.004 <https://doi.org/10.1016/j.marchem.2011.12.004> Marine Sciences Chemistry Publication - Article PeerReviewed 2012 ftnerc https://doi.org/10.1016/j.marchem.2011.12.004 2023-02-04T19:31:25Z The Southern Ocean is the world's largest high nutrient low chlorophyll (HNLC) region. However, satellite images highlight several areas associated with island chains and shallow topographic features which display high phytoplankton biomass. Here we present the first study of seasonal variations in phytoplankton biomass and ironavailability in the ScotiaSea over both austral spring and summer seasons. Based on dissolved iron (dFe) and Chlorophyll a (Chl a) concentrations, the study area is be divided into three regions: North of South Georgia, south of South Georgia and the vicinity of South Orkney Islands. The ScotiaSea to the south of South Georgia exhibited low dFe concentrations (< 0.027–0.05 nM) in surface waters during both the spring and summer seasons. Nevertheless, nitrate concentrations were considerably lower in spring compared to summer (difference ~ 8 μM). Summer Chl a concentrations were ~ 1.4 mg m− 3 and in situ phytoplankton populations displayed evidence of iron stress, suggesting the development of seasonaliron limitation. Surface water dFe concentrations in the South Georgia bloom waters (north of the islands) were elevated and slightly lower during spring than summer (0.20 nM compared to 0.31 nM, P > 0.05). Nitrate concentrations were 16 μM lower in summer compared to spring, whilst Chl a standing stocks remained high. Enhanced dFe (~ 0.25 nM) and Chl a concentrations were furthermore observed in the vicinity of the South Orkney Islands, located in the southern ScotiaSea. Iron addition experiments showed that in situ phytoplankton were iron replete spring and summer north of South Georgia and in the vicinity of South Orkney Islands during summer. We thus suggest that increased iron supply in high productivity areas including the area north of South Georgia and the South Orkney Islands, was sustained by a continuous benthic supply from their shelf systems, with a potential additional input from seasonally retreating sea ice in the South Orkney system. Article in Journal/Newspaper Scotia Sea Sea ice South Orkney Islands Southern Ocean Natural Environment Research Council: NERC Open Research Archive Southern Ocean Austral Scotia Sea South Orkney Islands ENVELOPE(-45.500,-45.500,-60.583,-60.583) Marine Chemistry 130-131 62 72 |
institution |
Open Polar |
collection |
Natural Environment Research Council: NERC Open Research Archive |
op_collection_id |
ftnerc |
language |
unknown |
topic |
Marine Sciences Chemistry |
spellingShingle |
Marine Sciences Chemistry Nielsdóttir, Maria C. Bibby, Thomas S. Moore, C. Mark Hinz, Daria J. Sanders, Richard Whitehouse, Michael Korb, Rebecca Achterberg, Eric P. Seasonal and spatial dynamics of iron availability in the Scotia Sea |
topic_facet |
Marine Sciences Chemistry |
description |
The Southern Ocean is the world's largest high nutrient low chlorophyll (HNLC) region. However, satellite images highlight several areas associated with island chains and shallow topographic features which display high phytoplankton biomass. Here we present the first study of seasonal variations in phytoplankton biomass and ironavailability in the ScotiaSea over both austral spring and summer seasons. Based on dissolved iron (dFe) and Chlorophyll a (Chl a) concentrations, the study area is be divided into three regions: North of South Georgia, south of South Georgia and the vicinity of South Orkney Islands. The ScotiaSea to the south of South Georgia exhibited low dFe concentrations (< 0.027–0.05 nM) in surface waters during both the spring and summer seasons. Nevertheless, nitrate concentrations were considerably lower in spring compared to summer (difference ~ 8 μM). Summer Chl a concentrations were ~ 1.4 mg m− 3 and in situ phytoplankton populations displayed evidence of iron stress, suggesting the development of seasonaliron limitation. Surface water dFe concentrations in the South Georgia bloom waters (north of the islands) were elevated and slightly lower during spring than summer (0.20 nM compared to 0.31 nM, P > 0.05). Nitrate concentrations were 16 μM lower in summer compared to spring, whilst Chl a standing stocks remained high. Enhanced dFe (~ 0.25 nM) and Chl a concentrations were furthermore observed in the vicinity of the South Orkney Islands, located in the southern ScotiaSea. Iron addition experiments showed that in situ phytoplankton were iron replete spring and summer north of South Georgia and in the vicinity of South Orkney Islands during summer. We thus suggest that increased iron supply in high productivity areas including the area north of South Georgia and the South Orkney Islands, was sustained by a continuous benthic supply from their shelf systems, with a potential additional input from seasonally retreating sea ice in the South Orkney system. |
format |
Article in Journal/Newspaper |
author |
Nielsdóttir, Maria C. Bibby, Thomas S. Moore, C. Mark Hinz, Daria J. Sanders, Richard Whitehouse, Michael Korb, Rebecca Achterberg, Eric P. |
author_facet |
Nielsdóttir, Maria C. Bibby, Thomas S. Moore, C. Mark Hinz, Daria J. Sanders, Richard Whitehouse, Michael Korb, Rebecca Achterberg, Eric P. |
author_sort |
Nielsdóttir, Maria C. |
title |
Seasonal and spatial dynamics of iron availability in the Scotia Sea |
title_short |
Seasonal and spatial dynamics of iron availability in the Scotia Sea |
title_full |
Seasonal and spatial dynamics of iron availability in the Scotia Sea |
title_fullStr |
Seasonal and spatial dynamics of iron availability in the Scotia Sea |
title_full_unstemmed |
Seasonal and spatial dynamics of iron availability in the Scotia Sea |
title_sort |
seasonal and spatial dynamics of iron availability in the scotia sea |
publisher |
Elsevier |
publishDate |
2012 |
url |
http://nora.nerc.ac.uk/id/eprint/17950/ http://www.sciencedirect.com/science/article/pii/S0304420311001320 |
long_lat |
ENVELOPE(-45.500,-45.500,-60.583,-60.583) |
geographic |
Southern Ocean Austral Scotia Sea South Orkney Islands |
geographic_facet |
Southern Ocean Austral Scotia Sea South Orkney Islands |
genre |
Scotia Sea Sea ice South Orkney Islands Southern Ocean |
genre_facet |
Scotia Sea Sea ice South Orkney Islands Southern Ocean |
op_relation |
Nielsdóttir, Maria C.; Bibby, Thomas S.; Moore, C. Mark; Hinz, Daria J.; Sanders, Richard orcid:0000-0002-6884-7131 Whitehouse, Michael; Korb, Rebecca; Achterberg, Eric P. 2012 Seasonal and spatial dynamics of iron availability in the Scotia Sea. Marine Chemistry, 130-131. 62-72. https://doi.org/10.1016/j.marchem.2011.12.004 <https://doi.org/10.1016/j.marchem.2011.12.004> |
op_doi |
https://doi.org/10.1016/j.marchem.2011.12.004 |
container_title |
Marine Chemistry |
container_volume |
130-131 |
container_start_page |
62 |
op_container_end_page |
72 |
_version_ |
1766189431929176064 |