Geochemical zones and environmental gradients for soils from the central Transantarctic Mountains, Antarctica
Previous studies have established links between biodiversity and soil geochemistry in the McMurdo Dry Valleys, Antarctica, where environmental gradients are important determinants of soil biodiversity. However, these gradients are not well established in the central Transantarctic Mountains, which a...
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ftcopernicus:oai:publications.copernicus.org:bg88839 2023-05-15T13:31:40+02:00 Geochemical zones and environmental gradients for soils from the central Transantarctic Mountains, Antarctica Diaz, Melisa A. Gardner, Christopher B. Welch, Susan A. Jackson, W. Andrew Adams, Byron J. Wall, Diana H. Hogg, Ian D. Fierer, Noah Lyons, W. Berry 2021-03-15 application/pdf https://doi.org/10.5194/bg-18-1629-2021 https://bg.copernicus.org/articles/18/1629/2021/ eng eng doi:10.5194/bg-18-1629-2021 https://bg.copernicus.org/articles/18/1629/2021/ eISSN: 1726-4189 Text 2021 ftcopernicus https://doi.org/10.5194/bg-18-1629-2021 2021-03-22T17:22:15Z Previous studies have established links between biodiversity and soil geochemistry in the McMurdo Dry Valleys, Antarctica, where environmental gradients are important determinants of soil biodiversity. However, these gradients are not well established in the central Transantarctic Mountains, which are thought to represent some of the least hospitable Antarctic soils. We analyzed 220 samples from 11 ice-free areas along the Shackleton Glacier ( ∼ 85 ∘ S), a major outlet glacier of the East Antarctic Ice Sheet. We established three zones of distinct geochemical gradients near the head of the glacier (upper), its central part (middle), and at the mouth (lower). The upper zone had the highest water-soluble salt concentrations with total salt concentrations exceeding 80 000 µ g g −1 , while the lower zone had the lowest water-soluble N:P ratios, suggesting that, in addition to other parameters (such as proximity to water and/or ice), the lower zone likely represents the most favorable ecological habitats. Given the strong dependence of geochemistry on geographic parameters, we developed multiple linear regression and random forest models to predict soil geochemical trends given latitude, longitude, elevation, distance from the coast, distance from the glacier, and soil moisture (variables which can be inferred from remote measurements). Confidence in our random forest model predictions was moderately high with R 2 values for total water-soluble salts, water-soluble N:P , ClO <math xmlns="http://www.w3.org/1998/Math/MathML" id="M8" display="inline" overflow="scroll" dspmath="mathml"><mrow><msubsup><mi/><mn mathvariant="normal">4</mn><mo>-</mo></msubsup></mrow></math> <svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="9pt" height="16pt" class="svg-formula" dspmath="mathimg" md5hash="a30bfde58a9ca9c078104c9522588f76"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="bg-18-1629-2021-ie00001.svg" width="9pt" height="16pt" src="bg-18-1629-2021-ie00001.png"/></svg:svg> , and ClO <math xmlns="http://www.w3.org/1998/Math/MathML" id="M9" display="inline" overflow="scroll" dspmath="mathml"><mrow><msubsup><mi/><mn mathvariant="normal">3</mn><mo>-</mo></msubsup></mrow></math> <svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="9pt" height="16pt" class="svg-formula" dspmath="mathimg" md5hash="1933cd4f78557ae19e1c84fa4d0b5473"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="bg-18-1629-2021-ie00002.svg" width="9pt" height="16pt" src="bg-18-1629-2021-ie00002.png"/></svg:svg> of 0.81, 0.88, 0.78, and 0.74, respectively. These modeling results can be used to predict geochemical gradients and estimate salt concentrations for other Transantarctic Mountain soils, information that can ultimately be used to better predict distributions of soil biota in this remote region. Text Antarc* Antarctic Antarctica Ice Sheet McMurdo Dry Valleys Shackleton Glacier Copernicus Publications: E-Journals Antarctic East Antarctic Ice Sheet McMurdo Dry Valleys Shackleton Shackleton Glacier ENVELOPE(-37.200,-37.200,-54.133,-54.133) Transantarctic Mountains Biogeosciences 18 5 1629 1644 |
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Open Polar |
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Copernicus Publications: E-Journals |
op_collection_id |
ftcopernicus |
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English |
description |
Previous studies have established links between biodiversity and soil geochemistry in the McMurdo Dry Valleys, Antarctica, where environmental gradients are important determinants of soil biodiversity. However, these gradients are not well established in the central Transantarctic Mountains, which are thought to represent some of the least hospitable Antarctic soils. We analyzed 220 samples from 11 ice-free areas along the Shackleton Glacier ( ∼ 85 ∘ S), a major outlet glacier of the East Antarctic Ice Sheet. We established three zones of distinct geochemical gradients near the head of the glacier (upper), its central part (middle), and at the mouth (lower). The upper zone had the highest water-soluble salt concentrations with total salt concentrations exceeding 80 000 µ g g −1 , while the lower zone had the lowest water-soluble N:P ratios, suggesting that, in addition to other parameters (such as proximity to water and/or ice), the lower zone likely represents the most favorable ecological habitats. Given the strong dependence of geochemistry on geographic parameters, we developed multiple linear regression and random forest models to predict soil geochemical trends given latitude, longitude, elevation, distance from the coast, distance from the glacier, and soil moisture (variables which can be inferred from remote measurements). Confidence in our random forest model predictions was moderately high with R 2 values for total water-soluble salts, water-soluble N:P , ClO <math xmlns="http://www.w3.org/1998/Math/MathML" id="M8" display="inline" overflow="scroll" dspmath="mathml"><mrow><msubsup><mi/><mn mathvariant="normal">4</mn><mo>-</mo></msubsup></mrow></math> <svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="9pt" height="16pt" class="svg-formula" dspmath="mathimg" md5hash="a30bfde58a9ca9c078104c9522588f76"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="bg-18-1629-2021-ie00001.svg" width="9pt" height="16pt" src="bg-18-1629-2021-ie00001.png"/></svg:svg> , and ClO <math xmlns="http://www.w3.org/1998/Math/MathML" id="M9" display="inline" overflow="scroll" dspmath="mathml"><mrow><msubsup><mi/><mn mathvariant="normal">3</mn><mo>-</mo></msubsup></mrow></math> <svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="9pt" height="16pt" class="svg-formula" dspmath="mathimg" md5hash="1933cd4f78557ae19e1c84fa4d0b5473"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="bg-18-1629-2021-ie00002.svg" width="9pt" height="16pt" src="bg-18-1629-2021-ie00002.png"/></svg:svg> of 0.81, 0.88, 0.78, and 0.74, respectively. These modeling results can be used to predict geochemical gradients and estimate salt concentrations for other Transantarctic Mountain soils, information that can ultimately be used to better predict distributions of soil biota in this remote region. |
format |
Text |
author |
Diaz, Melisa A. Gardner, Christopher B. Welch, Susan A. Jackson, W. Andrew Adams, Byron J. Wall, Diana H. Hogg, Ian D. Fierer, Noah Lyons, W. Berry |
spellingShingle |
Diaz, Melisa A. Gardner, Christopher B. Welch, Susan A. Jackson, W. Andrew Adams, Byron J. Wall, Diana H. Hogg, Ian D. Fierer, Noah Lyons, W. Berry Geochemical zones and environmental gradients for soils from the central Transantarctic Mountains, Antarctica |
author_facet |
Diaz, Melisa A. Gardner, Christopher B. Welch, Susan A. Jackson, W. Andrew Adams, Byron J. Wall, Diana H. Hogg, Ian D. Fierer, Noah Lyons, W. Berry |
author_sort |
Diaz, Melisa A. |
title |
Geochemical zones and environmental gradients for soils from the central Transantarctic Mountains, Antarctica |
title_short |
Geochemical zones and environmental gradients for soils from the central Transantarctic Mountains, Antarctica |
title_full |
Geochemical zones and environmental gradients for soils from the central Transantarctic Mountains, Antarctica |
title_fullStr |
Geochemical zones and environmental gradients for soils from the central Transantarctic Mountains, Antarctica |
title_full_unstemmed |
Geochemical zones and environmental gradients for soils from the central Transantarctic Mountains, Antarctica |
title_sort |
geochemical zones and environmental gradients for soils from the central transantarctic mountains, antarctica |
publishDate |
2021 |
url |
https://doi.org/10.5194/bg-18-1629-2021 https://bg.copernicus.org/articles/18/1629/2021/ |
long_lat |
ENVELOPE(-37.200,-37.200,-54.133,-54.133) |
geographic |
Antarctic East Antarctic Ice Sheet McMurdo Dry Valleys Shackleton Shackleton Glacier Transantarctic Mountains |
geographic_facet |
Antarctic East Antarctic Ice Sheet McMurdo Dry Valleys Shackleton Shackleton Glacier Transantarctic Mountains |
genre |
Antarc* Antarctic Antarctica Ice Sheet McMurdo Dry Valleys Shackleton Glacier |
genre_facet |
Antarc* Antarctic Antarctica Ice Sheet McMurdo Dry Valleys Shackleton Glacier |
op_source |
eISSN: 1726-4189 |
op_relation |
doi:10.5194/bg-18-1629-2021 https://bg.copernicus.org/articles/18/1629/2021/ |
op_doi |
https://doi.org/10.5194/bg-18-1629-2021 |
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Biogeosciences |
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18 |
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5 |
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1629 |
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1644 |
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1766020062645321728 |