Qualitative and quantitative reconstructions of surface water characteristics and recent hydrographical changes in the Trondheimsfjord, central Norway
International audience In the present study we investigated dinocyst assemblages in the Trondheimsfjord over the last 25 to 50 yr from three well-dated multi-cores (210 Pb and 137 Cs) retrieved along the fjord axis. The downcore distribution of the dinocysts is discussed in view of changes in key hy...
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ftunivnantes:oai:HAL:hal-02129072v1 2023-05-15T17:36:17+02:00 Qualitative and quantitative reconstructions of surface water characteristics and recent hydrographical changes in the Trondheimsfjord, central Norway Milzer, G. Giraudeau, J. Schmidt, S. Eynaud, F. Faust, J. Environnements et Paléoenvironnements OCéaniques (EPOC) Observatoire aquitain des sciences de l'univers (OASU) Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-École pratique des hautes études (EPHE) Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS) 2014 https://hal.science/hal-02129072 https://hal.science/hal-02129072/document https://hal.science/hal-02129072/file/Milzer-2014.pdf https://doi.org/10.5194/cp-10-305-2014 en eng HAL CCSD European Geosciences Union (EGU) info:eu-repo/semantics/altIdentifier/doi/10.5194/cp-10-305-2014 hal-02129072 https://hal.science/hal-02129072 https://hal.science/hal-02129072/document https://hal.science/hal-02129072/file/Milzer-2014.pdf doi:10.5194/cp-10-305-2014 info:eu-repo/semantics/OpenAccess ISSN: 1814-9324 EISSN: 1814-9332 Climate of the Past https://hal.science/hal-02129072 Climate of the Past, 2014, 10 (1), pp.305-323. ⟨10.5194/cp-10-305-2014⟩ [SDU.STU.OC]Sciences of the Universe [physics]/Earth Sciences/Oceanography [SDU.STU.CL]Sciences of the Universe [physics]/Earth Sciences/Climatology info:eu-repo/semantics/article Journal articles 2014 ftunivnantes https://doi.org/10.5194/cp-10-305-2014 2023-02-08T07:40:47Z International audience In the present study we investigated dinocyst assemblages in the Trondheimsfjord over the last 25 to 50 yr from three well-dated multi-cores (210 Pb and 137 Cs) retrieved along the fjord axis. The downcore distribution of the dinocysts is discussed in view of changes in key hydro-graphic parameters of the surface waters (sea-surface temperatures (SSTs), sea-surface salinities (SSSs), and river discharges) monitored in the fjord. We examine the impact of the North Atlantic Oscillation pattern and of waste water supply from the local industry and agriculture on the fjord ecological state and thus dinocyst species diversity. Our results show that dinocyst production and diversity in the fjord is not evidently affected by human-induced eutrophication. Instead the assemblages appear to be mainly controlled by the NAO-related changes in nutrient availability and the physico-chemical characteristics of the surface mixed layer. Still, discharges of major rivers have been modulated since 1985 by the implementation of hydropower plants, which certainly influences the amounts of nutrients supplied to the fjord. The impact, however, is variable according to the local geographical setting, and barely differentiated from natural changes in river run off. We ultimately test the use of the modern analogue technique (MAT) for the reconstruction of winter and summer SSTs and SSSs and annual primary productivity (PP) in this particular fjord setting. The reconstructed data are compared with time series of summer and winter SSTs and SSSs measured at 10 m water depth, as well as with mean annual PPs along the Norwegian coast and in Scandinavian fjords. The reconstructions are generally in good agreement with the instrumental measurements and observations from other fjords. Major deviations can be attributed to peculiarities in the assemblages linked to the particular fjord setting and the related hydrological structure. Article in Journal/Newspaper North Atlantic North Atlantic oscillation Université de Nantes: HAL-UNIV-NANTES Norway Climate of the Past 10 1 305 323 |
institution |
Open Polar |
collection |
Université de Nantes: HAL-UNIV-NANTES |
op_collection_id |
ftunivnantes |
language |
English |
topic |
[SDU.STU.OC]Sciences of the Universe [physics]/Earth Sciences/Oceanography [SDU.STU.CL]Sciences of the Universe [physics]/Earth Sciences/Climatology |
spellingShingle |
[SDU.STU.OC]Sciences of the Universe [physics]/Earth Sciences/Oceanography [SDU.STU.CL]Sciences of the Universe [physics]/Earth Sciences/Climatology Milzer, G. Giraudeau, J. Schmidt, S. Eynaud, F. Faust, J. Qualitative and quantitative reconstructions of surface water characteristics and recent hydrographical changes in the Trondheimsfjord, central Norway |
topic_facet |
[SDU.STU.OC]Sciences of the Universe [physics]/Earth Sciences/Oceanography [SDU.STU.CL]Sciences of the Universe [physics]/Earth Sciences/Climatology |
description |
International audience In the present study we investigated dinocyst assemblages in the Trondheimsfjord over the last 25 to 50 yr from three well-dated multi-cores (210 Pb and 137 Cs) retrieved along the fjord axis. The downcore distribution of the dinocysts is discussed in view of changes in key hydro-graphic parameters of the surface waters (sea-surface temperatures (SSTs), sea-surface salinities (SSSs), and river discharges) monitored in the fjord. We examine the impact of the North Atlantic Oscillation pattern and of waste water supply from the local industry and agriculture on the fjord ecological state and thus dinocyst species diversity. Our results show that dinocyst production and diversity in the fjord is not evidently affected by human-induced eutrophication. Instead the assemblages appear to be mainly controlled by the NAO-related changes in nutrient availability and the physico-chemical characteristics of the surface mixed layer. Still, discharges of major rivers have been modulated since 1985 by the implementation of hydropower plants, which certainly influences the amounts of nutrients supplied to the fjord. The impact, however, is variable according to the local geographical setting, and barely differentiated from natural changes in river run off. We ultimately test the use of the modern analogue technique (MAT) for the reconstruction of winter and summer SSTs and SSSs and annual primary productivity (PP) in this particular fjord setting. The reconstructed data are compared with time series of summer and winter SSTs and SSSs measured at 10 m water depth, as well as with mean annual PPs along the Norwegian coast and in Scandinavian fjords. The reconstructions are generally in good agreement with the instrumental measurements and observations from other fjords. Major deviations can be attributed to peculiarities in the assemblages linked to the particular fjord setting and the related hydrological structure. |
author2 |
Environnements et Paléoenvironnements OCéaniques (EPOC) Observatoire aquitain des sciences de l'univers (OASU) Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-École pratique des hautes études (EPHE) Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS) |
format |
Article in Journal/Newspaper |
author |
Milzer, G. Giraudeau, J. Schmidt, S. Eynaud, F. Faust, J. |
author_facet |
Milzer, G. Giraudeau, J. Schmidt, S. Eynaud, F. Faust, J. |
author_sort |
Milzer, G. |
title |
Qualitative and quantitative reconstructions of surface water characteristics and recent hydrographical changes in the Trondheimsfjord, central Norway |
title_short |
Qualitative and quantitative reconstructions of surface water characteristics and recent hydrographical changes in the Trondheimsfjord, central Norway |
title_full |
Qualitative and quantitative reconstructions of surface water characteristics and recent hydrographical changes in the Trondheimsfjord, central Norway |
title_fullStr |
Qualitative and quantitative reconstructions of surface water characteristics and recent hydrographical changes in the Trondheimsfjord, central Norway |
title_full_unstemmed |
Qualitative and quantitative reconstructions of surface water characteristics and recent hydrographical changes in the Trondheimsfjord, central Norway |
title_sort |
qualitative and quantitative reconstructions of surface water characteristics and recent hydrographical changes in the trondheimsfjord, central norway |
publisher |
HAL CCSD |
publishDate |
2014 |
url |
https://hal.science/hal-02129072 https://hal.science/hal-02129072/document https://hal.science/hal-02129072/file/Milzer-2014.pdf https://doi.org/10.5194/cp-10-305-2014 |
geographic |
Norway |
geographic_facet |
Norway |
genre |
North Atlantic North Atlantic oscillation |
genre_facet |
North Atlantic North Atlantic oscillation |
op_source |
ISSN: 1814-9324 EISSN: 1814-9332 Climate of the Past https://hal.science/hal-02129072 Climate of the Past, 2014, 10 (1), pp.305-323. ⟨10.5194/cp-10-305-2014⟩ |
op_relation |
info:eu-repo/semantics/altIdentifier/doi/10.5194/cp-10-305-2014 hal-02129072 https://hal.science/hal-02129072 https://hal.science/hal-02129072/document https://hal.science/hal-02129072/file/Milzer-2014.pdf doi:10.5194/cp-10-305-2014 |
op_rights |
info:eu-repo/semantics/OpenAccess |
op_doi |
https://doi.org/10.5194/cp-10-305-2014 |
container_title |
Climate of the Past |
container_volume |
10 |
container_issue |
1 |
container_start_page |
305 |
op_container_end_page |
323 |
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1766135719492845568 |