Palaeoproductivity changes and upwelling variability in the Galicia Mud Patch during the last 5000 years: geochemical and microfloral evidence
12 páginas, 4 figuras, 3 tablas The Holocene palaeoclimatic history of the Galician continental shelf has been investigated through the analyses of diatom remains, other siliceous compounds, biogenic silica (BSi) and metals content in a multiproxy approach to a gravity core recovered from the Galici...
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2008
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Online Access: | http://hdl.handle.net/10261/49587 https://doi.org/10.1177/0959683608096596 |
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ftcsic:oai:digital.csic.es:10261/49587 2024-02-11T10:05:15+01:00 Palaeoproductivity changes and upwelling variability in the Galicia Mud Patch during the last 5000 years: geochemical and microfloral evidence Bernárdez, Patricia González-Álvarez, R. Francés, Guillermo Prego, R. Bárcena, María Ángeles Romero, Oscar E. 2008 http://hdl.handle.net/10261/49587 https://doi.org/10.1177/0959683608096596 en eng Sage Publications http://dx.doi.org/10.1177/0959683608096596 Sí Holocene 18(8): 1207-1218 (2008) 0959-6836 http://hdl.handle.net/10261/49587 doi:10.1177/0959683608096596 1477-0911 open Metals Geochemistry Diatom assemblages Late holocene Palaeoproductivity Upwelling Palaeoclimate NW Iberian Peninsula Galicia Mud Patch Palaeoceanography artículo http://purl.org/coar/resource_type/c_6501 2008 ftcsic https://doi.org/10.1177/0959683608096596 2024-01-16T09:37:45Z 12 páginas, 4 figuras, 3 tablas The Holocene palaeoclimatic history of the Galician continental shelf has been investigated through the analyses of diatom remains, other siliceous compounds, biogenic silica (BSi) and metals content in a multiproxy approach to a gravity core recovered from the Galicia Mud Patch, NW Iberian Peninsula, covering the last 5000 years. Downcore changes in diatom assemblages composition and abundance reflect changes in diatom production related to long-/short-term variations in climate, regional oceanography, upwelling strength and river influx off the coast of NW Spain and Portugal. Palaeoclimatic variability was related to the relative strengths and position of the Azores High and Iceland Low pressure cells. Metals and microflora fluctuations are interpreted as changes in the riverine influence and upwelling intensity paced by oceanographic, atmospheric and climatic changes. Lack of diatoms between 4700—3300 and 1800—1200 cal. yr BP could be linked to early diagenetic processes taking place in the sediment after burial. Biogenic barium (Baexcess), metals and excess diatom assemblages, show a general increase of marine productivity for the last 1200 cal. yr BP. Between 800 and 500 cal. yr BP high production of the microflora is triggered by influx of river-derived nutrients under conditions of SW winds and storms resulting from a NAO negative-like phase. The biosiliceous and geochemical signatures of sediments from the last 500 cal. yr BP indicate conditions of enhanced upwelling and increased phytoplanktonic production associated with the intensification of northerly winds. Upwelling strengthening in this area, attributed to recent global warming, could provoke an increase in phytoplankton biomass with consequent biological, climatological and socioeconomical impacts. The imprint of anthropic activities has been recorded by the increasing Pb/Al ratios for the last 400 cal. yr BP. Funding for this study was received from the MECD and Xunta de Galicia under the projects ... Article in Journal/Newspaper Iceland Digital.CSIC (Spanish National Research Council) The Holocene 18 8 1207 1218 |
institution |
Open Polar |
collection |
Digital.CSIC (Spanish National Research Council) |
op_collection_id |
ftcsic |
language |
English |
topic |
Metals Geochemistry Diatom assemblages Late holocene Palaeoproductivity Upwelling Palaeoclimate NW Iberian Peninsula Galicia Mud Patch Palaeoceanography |
spellingShingle |
Metals Geochemistry Diatom assemblages Late holocene Palaeoproductivity Upwelling Palaeoclimate NW Iberian Peninsula Galicia Mud Patch Palaeoceanography Bernárdez, Patricia González-Álvarez, R. Francés, Guillermo Prego, R. Bárcena, María Ángeles Romero, Oscar E. Palaeoproductivity changes and upwelling variability in the Galicia Mud Patch during the last 5000 years: geochemical and microfloral evidence |
topic_facet |
Metals Geochemistry Diatom assemblages Late holocene Palaeoproductivity Upwelling Palaeoclimate NW Iberian Peninsula Galicia Mud Patch Palaeoceanography |
description |
12 páginas, 4 figuras, 3 tablas The Holocene palaeoclimatic history of the Galician continental shelf has been investigated through the analyses of diatom remains, other siliceous compounds, biogenic silica (BSi) and metals content in a multiproxy approach to a gravity core recovered from the Galicia Mud Patch, NW Iberian Peninsula, covering the last 5000 years. Downcore changes in diatom assemblages composition and abundance reflect changes in diatom production related to long-/short-term variations in climate, regional oceanography, upwelling strength and river influx off the coast of NW Spain and Portugal. Palaeoclimatic variability was related to the relative strengths and position of the Azores High and Iceland Low pressure cells. Metals and microflora fluctuations are interpreted as changes in the riverine influence and upwelling intensity paced by oceanographic, atmospheric and climatic changes. Lack of diatoms between 4700—3300 and 1800—1200 cal. yr BP could be linked to early diagenetic processes taking place in the sediment after burial. Biogenic barium (Baexcess), metals and excess diatom assemblages, show a general increase of marine productivity for the last 1200 cal. yr BP. Between 800 and 500 cal. yr BP high production of the microflora is triggered by influx of river-derived nutrients under conditions of SW winds and storms resulting from a NAO negative-like phase. The biosiliceous and geochemical signatures of sediments from the last 500 cal. yr BP indicate conditions of enhanced upwelling and increased phytoplanktonic production associated with the intensification of northerly winds. Upwelling strengthening in this area, attributed to recent global warming, could provoke an increase in phytoplankton biomass with consequent biological, climatological and socioeconomical impacts. The imprint of anthropic activities has been recorded by the increasing Pb/Al ratios for the last 400 cal. yr BP. Funding for this study was received from the MECD and Xunta de Galicia under the projects ... |
format |
Article in Journal/Newspaper |
author |
Bernárdez, Patricia González-Álvarez, R. Francés, Guillermo Prego, R. Bárcena, María Ángeles Romero, Oscar E. |
author_facet |
Bernárdez, Patricia González-Álvarez, R. Francés, Guillermo Prego, R. Bárcena, María Ángeles Romero, Oscar E. |
author_sort |
Bernárdez, Patricia |
title |
Palaeoproductivity changes and upwelling variability in the Galicia Mud Patch during the last 5000 years: geochemical and microfloral evidence |
title_short |
Palaeoproductivity changes and upwelling variability in the Galicia Mud Patch during the last 5000 years: geochemical and microfloral evidence |
title_full |
Palaeoproductivity changes and upwelling variability in the Galicia Mud Patch during the last 5000 years: geochemical and microfloral evidence |
title_fullStr |
Palaeoproductivity changes and upwelling variability in the Galicia Mud Patch during the last 5000 years: geochemical and microfloral evidence |
title_full_unstemmed |
Palaeoproductivity changes and upwelling variability in the Galicia Mud Patch during the last 5000 years: geochemical and microfloral evidence |
title_sort |
palaeoproductivity changes and upwelling variability in the galicia mud patch during the last 5000 years: geochemical and microfloral evidence |
publisher |
Sage Publications |
publishDate |
2008 |
url |
http://hdl.handle.net/10261/49587 https://doi.org/10.1177/0959683608096596 |
genre |
Iceland |
genre_facet |
Iceland |
op_relation |
http://dx.doi.org/10.1177/0959683608096596 Sí Holocene 18(8): 1207-1218 (2008) 0959-6836 http://hdl.handle.net/10261/49587 doi:10.1177/0959683608096596 1477-0911 |
op_rights |
open |
op_doi |
https://doi.org/10.1177/0959683608096596 |
container_title |
The Holocene |
container_volume |
18 |
container_issue |
8 |
container_start_page |
1207 |
op_container_end_page |
1218 |
_version_ |
1790602158700232704 |