The last forests on Antarctica:reconstructing flora and temperature from the Neogene Sirius Group, Transantarctic Mountains
Fossil-bearing deposits in the Transantarctic Mountains, Antarctica indicate that, despite the cold nature of the continent’s climate, a tundra ecosystem grew during periods of ice sheet retreat in the mid to late Neogene (17–2.5 Ma), 480 km from the South Pole. To date, palaeotemperature reconstruc...
Published in: | Organic Geochemistry |
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Main Authors: | , , , , , , , |
Format: | Article in Journal/Newspaper |
Language: | English |
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2018
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Online Access: | https://risweb.st-andrews.ac.uk/portal/en/researchoutput/the-last-forests-on-antarctica(ce9d4176-2044-493d-b599-9cf1fa0a744a).html https://doi.org/10.1016/j.orggeochem.2018.01.001 https://research-repository.st-andrews.ac.uk/bitstream/10023/12701/1/Rees_Owen_2018_OR_LastForests_CC.pdf |
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ftunstandrewcris:oai:risweb.st-andrews.ac.uk:publications/ce9d4176-2044-493d-b599-9cf1fa0a744a 2023-05-15T13:39:30+02:00 The last forests on Antarctica:reconstructing flora and temperature from the Neogene Sirius Group, Transantarctic Mountains Rees-Owen, Rhian L. Gill, Fiona L. Newton, Robert J. Ivanovic, Ruza F. Francis, Jane E. Riding, James B. Vane, Christopher H. Lopes dos Santos, Raquel A. 2018-04 application/pdf https://risweb.st-andrews.ac.uk/portal/en/researchoutput/the-last-forests-on-antarctica(ce9d4176-2044-493d-b599-9cf1fa0a744a).html https://doi.org/10.1016/j.orggeochem.2018.01.001 https://research-repository.st-andrews.ac.uk/bitstream/10023/12701/1/Rees_Owen_2018_OR_LastForests_CC.pdf eng eng info:eu-repo/semantics/openAccess Rees-Owen , R L , Gill , F L , Newton , R J , Ivanovic , R F , Francis , J E , Riding , J B , Vane , C H & Lopes dos Santos , R A 2018 , ' The last forests on Antarctica : reconstructing flora and temperature from the Neogene Sirius Group, Transantarctic Mountains ' , Organic Geochemistry , vol. 118 , pp. 4-14 . https://doi.org/10.1016/j.orggeochem.2018.01.001 Antarctica Neogene Sirius Group Terpenoid GDGT Palaeovegetation Palaeotemperature Palaeoenvironment article 2018 ftunstandrewcris https://doi.org/10.1016/j.orggeochem.2018.01.001 2022-06-02T07:48:13Z Fossil-bearing deposits in the Transantarctic Mountains, Antarctica indicate that, despite the cold nature of the continent’s climate, a tundra ecosystem grew during periods of ice sheet retreat in the mid to late Neogene (17–2.5 Ma), 480 km from the South Pole. To date, palaeotemperature reconstruction has been based only on biological ranges, thereby calling for a geochemical approach to understanding continental climate and environment. There is contradictory evidence in the fossil record as to whether this flora was mixed angiosperm-conifer vegetation, or whether by this point conifers had disappeared from the continent. In order to address these questions, we have analysed, for the first time in sediments of this age, plant and bacterial biomarkers in terrestrial sediments from the Transantarctic Mountains to reconstruct past temperature and vegetation during a period of East Antarctic Ice Sheet retreat. From tetraether lipids (MBT’/CBT palaeothermometer), we conclude that the mean continental summer temperature was ca. 5 °C, in agreement with previous reconstructions. This was warm enough to have allowed woody vegetation to survive and reproduce even during the austral winter. Biomarkers from vascular plants indicate a low diversity and spatially variable flora consisting of higher plants, moss and algal mats growing in microenvironments in a glacial outwash system. Abietane-type compounds were abundant in some samples, indicating that conifers, most likely Podocarpaceae, grew on the Antarctic continent well into the Neogene. This is supported by the palynological record, but not the macrofossil record for the continent, and has implications for the evolution of vegetation on Antarctica. Article in Journal/Newspaper Antarc* Antarctic Antarctica Ice Sheet South pole South pole Tundra University of St Andrews: Research Portal Antarctic Austral East Antarctic Ice Sheet Sirius ENVELOPE(163.250,163.250,-84.133,-84.133) South Pole The Antarctic Transantarctic Mountains Organic Geochemistry 118 4 14 |
institution |
Open Polar |
collection |
University of St Andrews: Research Portal |
op_collection_id |
ftunstandrewcris |
language |
English |
topic |
Antarctica Neogene Sirius Group Terpenoid GDGT Palaeovegetation Palaeotemperature Palaeoenvironment |
spellingShingle |
Antarctica Neogene Sirius Group Terpenoid GDGT Palaeovegetation Palaeotemperature Palaeoenvironment Rees-Owen, Rhian L. Gill, Fiona L. Newton, Robert J. Ivanovic, Ruza F. Francis, Jane E. Riding, James B. Vane, Christopher H. Lopes dos Santos, Raquel A. The last forests on Antarctica:reconstructing flora and temperature from the Neogene Sirius Group, Transantarctic Mountains |
topic_facet |
Antarctica Neogene Sirius Group Terpenoid GDGT Palaeovegetation Palaeotemperature Palaeoenvironment |
description |
Fossil-bearing deposits in the Transantarctic Mountains, Antarctica indicate that, despite the cold nature of the continent’s climate, a tundra ecosystem grew during periods of ice sheet retreat in the mid to late Neogene (17–2.5 Ma), 480 km from the South Pole. To date, palaeotemperature reconstruction has been based only on biological ranges, thereby calling for a geochemical approach to understanding continental climate and environment. There is contradictory evidence in the fossil record as to whether this flora was mixed angiosperm-conifer vegetation, or whether by this point conifers had disappeared from the continent. In order to address these questions, we have analysed, for the first time in sediments of this age, plant and bacterial biomarkers in terrestrial sediments from the Transantarctic Mountains to reconstruct past temperature and vegetation during a period of East Antarctic Ice Sheet retreat. From tetraether lipids (MBT’/CBT palaeothermometer), we conclude that the mean continental summer temperature was ca. 5 °C, in agreement with previous reconstructions. This was warm enough to have allowed woody vegetation to survive and reproduce even during the austral winter. Biomarkers from vascular plants indicate a low diversity and spatially variable flora consisting of higher plants, moss and algal mats growing in microenvironments in a glacial outwash system. Abietane-type compounds were abundant in some samples, indicating that conifers, most likely Podocarpaceae, grew on the Antarctic continent well into the Neogene. This is supported by the palynological record, but not the macrofossil record for the continent, and has implications for the evolution of vegetation on Antarctica. |
format |
Article in Journal/Newspaper |
author |
Rees-Owen, Rhian L. Gill, Fiona L. Newton, Robert J. Ivanovic, Ruza F. Francis, Jane E. Riding, James B. Vane, Christopher H. Lopes dos Santos, Raquel A. |
author_facet |
Rees-Owen, Rhian L. Gill, Fiona L. Newton, Robert J. Ivanovic, Ruza F. Francis, Jane E. Riding, James B. Vane, Christopher H. Lopes dos Santos, Raquel A. |
author_sort |
Rees-Owen, Rhian L. |
title |
The last forests on Antarctica:reconstructing flora and temperature from the Neogene Sirius Group, Transantarctic Mountains |
title_short |
The last forests on Antarctica:reconstructing flora and temperature from the Neogene Sirius Group, Transantarctic Mountains |
title_full |
The last forests on Antarctica:reconstructing flora and temperature from the Neogene Sirius Group, Transantarctic Mountains |
title_fullStr |
The last forests on Antarctica:reconstructing flora and temperature from the Neogene Sirius Group, Transantarctic Mountains |
title_full_unstemmed |
The last forests on Antarctica:reconstructing flora and temperature from the Neogene Sirius Group, Transantarctic Mountains |
title_sort |
last forests on antarctica:reconstructing flora and temperature from the neogene sirius group, transantarctic mountains |
publishDate |
2018 |
url |
https://risweb.st-andrews.ac.uk/portal/en/researchoutput/the-last-forests-on-antarctica(ce9d4176-2044-493d-b599-9cf1fa0a744a).html https://doi.org/10.1016/j.orggeochem.2018.01.001 https://research-repository.st-andrews.ac.uk/bitstream/10023/12701/1/Rees_Owen_2018_OR_LastForests_CC.pdf |
long_lat |
ENVELOPE(163.250,163.250,-84.133,-84.133) |
geographic |
Antarctic Austral East Antarctic Ice Sheet Sirius South Pole The Antarctic Transantarctic Mountains |
geographic_facet |
Antarctic Austral East Antarctic Ice Sheet Sirius South Pole The Antarctic Transantarctic Mountains |
genre |
Antarc* Antarctic Antarctica Ice Sheet South pole South pole Tundra |
genre_facet |
Antarc* Antarctic Antarctica Ice Sheet South pole South pole Tundra |
op_source |
Rees-Owen , R L , Gill , F L , Newton , R J , Ivanovic , R F , Francis , J E , Riding , J B , Vane , C H & Lopes dos Santos , R A 2018 , ' The last forests on Antarctica : reconstructing flora and temperature from the Neogene Sirius Group, Transantarctic Mountains ' , Organic Geochemistry , vol. 118 , pp. 4-14 . https://doi.org/10.1016/j.orggeochem.2018.01.001 |
op_rights |
info:eu-repo/semantics/openAccess |
op_doi |
https://doi.org/10.1016/j.orggeochem.2018.01.001 |
container_title |
Organic Geochemistry |
container_volume |
118 |
container_start_page |
4 |
op_container_end_page |
14 |
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1766119670265413632 |