Environmental responses to the 9.7 and 8.2 cold events at two ecotonal sites in the Dovre mountains, mid-Norway
We found strong signals of two cooling events around 9700 and 8200 cal yrs. BP in lakes Store Finnsjøen and Flåfattjønna at Dovre, mid-Norway. Analyses included pollen in both lakes, and C/N-ratio, biomarkers (e.g. alkanes and br-GDGTs), and XRF scanning in Finnsjøen. The positions of these lakes cl...
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ftunivbergen:oai:bora.uib.no:1956/22716 2023-05-15T16:41:16+02:00 Environmental responses to the 9.7 and 8.2 cold events at two ecotonal sites in the Dovre mountains, mid-Norway Paus, Aage Haflidason, Haflidi Routh, Joyanto Naafs, B. David A. Thoen, Mari Woxen 2019-11-15T09:37:45Z application/pdf https://hdl.handle.net/1956/22716 https://doi.org/10.1016/j.quascirev.2018.12.009 eng eng Elsevier urn:issn:0277-3791 urn:issn:1873-457X https://hdl.handle.net/1956/22716 https://doi.org/10.1016/j.quascirev.2018.12.009 cristin:1668669 Quaternary Science Reviews. 2019;205:45-61 Attribution-NonCommercial-NoDerivs CC BY-NC-ND http://creativecommons.org/licenses/by-nc-nd/4.0/ Copyright 2019 Elsevier Quaternary Science Reviews 45-61 205 Peer reviewed Journal article 2019 ftunivbergen https://doi.org/10.1016/j.quascirev.2018.12.009 2023-03-14T17:44:00Z We found strong signals of two cooling events around 9700 and 8200 cal yrs. BP in lakes Store Finnsjøen and Flåfattjønna at Dovre, mid-Norway. Analyses included pollen in both lakes, and C/N-ratio, biomarkers (e.g. alkanes and br-GDGTs), and XRF scanning in Finnsjøen. The positions of these lakes close to ecotones (upper forest-lines of birch and pine, respectively) reduced their resilience to cold events causing vegetation regression at both sites. The global 8.2 event reflects the collapse of the Laurentide Ice Sheet. The 9.7 event with impact restricted to Scandinavia and traced by pollen at Dovre only, reflects the drainage of the Baltic Ancylus Lake. More detailed analysis in Finnsjøen shows that the events also caused increased allochtonous input (K, Ca), increased sedimentation rate, and decreased sediment density and aquatic production. br-GDGT-based temperatures indicate gradual cooling through the early Holocene. In Finnsjøen, ca. 3100 maxima-minima couplets in sediment density along the analysed sequence of ca. 3100 calibrated years show the presence of varves for the first time in Norway. Impact of the 9.7 and 8.2 events lasted ca. 60 and 370 years, respectively. Pine pollen percentages were halved and re-established in less than 60 years, indicating the reduction of pine pollen production and not vegetative growth during the 9.7 event. The local impact of the 8.2 event sensu lato (ca. 8420–8050 cal yrs. BP) divides the event into a precursor, an erosional phase, and a recovery phase. At the onset of the erosional phase, summer temperatures increased. acceptedVersion Article in Journal/Newspaper Ice Sheet University of Bergen: Bergen Open Research Archive (BORA-UiB) Norway Quaternary Science Reviews 205 45 61 |
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Open Polar |
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University of Bergen: Bergen Open Research Archive (BORA-UiB) |
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ftunivbergen |
language |
English |
description |
We found strong signals of two cooling events around 9700 and 8200 cal yrs. BP in lakes Store Finnsjøen and Flåfattjønna at Dovre, mid-Norway. Analyses included pollen in both lakes, and C/N-ratio, biomarkers (e.g. alkanes and br-GDGTs), and XRF scanning in Finnsjøen. The positions of these lakes close to ecotones (upper forest-lines of birch and pine, respectively) reduced their resilience to cold events causing vegetation regression at both sites. The global 8.2 event reflects the collapse of the Laurentide Ice Sheet. The 9.7 event with impact restricted to Scandinavia and traced by pollen at Dovre only, reflects the drainage of the Baltic Ancylus Lake. More detailed analysis in Finnsjøen shows that the events also caused increased allochtonous input (K, Ca), increased sedimentation rate, and decreased sediment density and aquatic production. br-GDGT-based temperatures indicate gradual cooling through the early Holocene. In Finnsjøen, ca. 3100 maxima-minima couplets in sediment density along the analysed sequence of ca. 3100 calibrated years show the presence of varves for the first time in Norway. Impact of the 9.7 and 8.2 events lasted ca. 60 and 370 years, respectively. Pine pollen percentages were halved and re-established in less than 60 years, indicating the reduction of pine pollen production and not vegetative growth during the 9.7 event. The local impact of the 8.2 event sensu lato (ca. 8420–8050 cal yrs. BP) divides the event into a precursor, an erosional phase, and a recovery phase. At the onset of the erosional phase, summer temperatures increased. acceptedVersion |
format |
Article in Journal/Newspaper |
author |
Paus, Aage Haflidason, Haflidi Routh, Joyanto Naafs, B. David A. Thoen, Mari Woxen |
spellingShingle |
Paus, Aage Haflidason, Haflidi Routh, Joyanto Naafs, B. David A. Thoen, Mari Woxen Environmental responses to the 9.7 and 8.2 cold events at two ecotonal sites in the Dovre mountains, mid-Norway |
author_facet |
Paus, Aage Haflidason, Haflidi Routh, Joyanto Naafs, B. David A. Thoen, Mari Woxen |
author_sort |
Paus, Aage |
title |
Environmental responses to the 9.7 and 8.2 cold events at two ecotonal sites in the Dovre mountains, mid-Norway |
title_short |
Environmental responses to the 9.7 and 8.2 cold events at two ecotonal sites in the Dovre mountains, mid-Norway |
title_full |
Environmental responses to the 9.7 and 8.2 cold events at two ecotonal sites in the Dovre mountains, mid-Norway |
title_fullStr |
Environmental responses to the 9.7 and 8.2 cold events at two ecotonal sites in the Dovre mountains, mid-Norway |
title_full_unstemmed |
Environmental responses to the 9.7 and 8.2 cold events at two ecotonal sites in the Dovre mountains, mid-Norway |
title_sort |
environmental responses to the 9.7 and 8.2 cold events at two ecotonal sites in the dovre mountains, mid-norway |
publisher |
Elsevier |
publishDate |
2019 |
url |
https://hdl.handle.net/1956/22716 https://doi.org/10.1016/j.quascirev.2018.12.009 |
geographic |
Norway |
geographic_facet |
Norway |
genre |
Ice Sheet |
genre_facet |
Ice Sheet |
op_source |
Quaternary Science Reviews 45-61 205 |
op_relation |
urn:issn:0277-3791 urn:issn:1873-457X https://hdl.handle.net/1956/22716 https://doi.org/10.1016/j.quascirev.2018.12.009 cristin:1668669 Quaternary Science Reviews. 2019;205:45-61 |
op_rights |
Attribution-NonCommercial-NoDerivs CC BY-NC-ND http://creativecommons.org/licenses/by-nc-nd/4.0/ Copyright 2019 Elsevier |
op_doi |
https://doi.org/10.1016/j.quascirev.2018.12.009 |
container_title |
Quaternary Science Reviews |
container_volume |
205 |
container_start_page |
45 |
op_container_end_page |
61 |
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1766031704062951424 |