Carbon geochemistry of plankton-dominated samples in the Laptev and East Siberian shelves: contrasts in suspended particle composition
Recent Arctic studies suggest that sea ice decline and permafrost thawing will affect phytoplankton dynamics and stimulate heterotrophic communities. However, in what way the plankton composition will change as the warming proceeds remains elusive. Here we investigate the chemical signature of the p...
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2018
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Online Access: | https://doi.org/10.5194/os-13-735-2017 https://os.copernicus.org/articles/13/735/2017/ |
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ftcopernicus:oai:publications.copernicus.org:os58258 2023-05-15T15:15:54+02:00 Carbon geochemistry of plankton-dominated samples in the Laptev and East Siberian shelves: contrasts in suspended particle composition Tesi, Tommaso Geibel, Marc C. Pearce, Christof Panova, Elena Vonk, Jorien E. Karlsson, Emma Salvado, Joan A. Kruså, Martin Bröder, Lisa Humborg, Christoph Semiletov, Igor Gustafsson, Örjan 2018-09-14 info:eu-repo/semantics/application/pdf https://doi.org/10.5194/os-13-735-2017 https://os.copernicus.org/articles/13/735/2017/ eng eng info:eu-repo/grantAgreement/EC/FP7/328049 info:eu-repo/grantAgreement/EC/FP7/300259 doi:10.5194/os-13-735-2017 https://os.copernicus.org/articles/13/735/2017/ info:eu-repo/semantics/openAccess eISSN: 1812-0792 info:eu-repo/semantics/Text 2018 ftcopernicus https://doi.org/10.5194/os-13-735-2017 2020-07-20T16:23:36Z Recent Arctic studies suggest that sea ice decline and permafrost thawing will affect phytoplankton dynamics and stimulate heterotrophic communities. However, in what way the plankton composition will change as the warming proceeds remains elusive. Here we investigate the chemical signature of the plankton-dominated fraction of particulate organic matter (POM) collected along the Siberian Shelf. POM (> 10 µm) samples were analysed using molecular biomarkers (CuO oxidation and IP 25 ) and dual-carbon isotopes ( δ 13 C and Δ 14 C). In addition, surface water chemical properties were integrated with the POM (> 10 µm) dataset to understand the link between plankton composition and environmental conditions. δ 13 C and Δ 14 C exhibited a large variability in the POM (> 10 µm) distribution while the content of terrestrial biomarkers in the POM was negligible. In the Laptev Sea (LS), δ 13 C and Δ 14 C of POM (> 10 µm) suggested a heterotrophic environment in which dissolved organic carbon (DOC) from the Lena River was the primary source of metabolisable carbon. Within the Lena plume, terrestrial DOC probably became part of the food web via bacteria uptake and subsequently transferred to relatively other heterotrophic communities (e.g. dinoflagellates). Moving eastwards toward the sea-ice-dominated East Siberian Sea (ESS), the system became progressively more autotrophic. Comparison between δ 13 C of POM (> 10 µm) samples and CO 2 aq concentrations revealed that the carbon isotope fractionation increased moving towards the easternmost and most productive stations. In a warming scenario characterised by enhanced terrestrial DOC release (thawing permafrost) and progressive sea ice decline, heterotrophic conditions might persist in the LS while the nutrient-rich Pacific inflow will likely stimulate greater primary productivity in the ESS. The contrasting trophic conditions will result in a sharp gradient in δ 13 C between the LS and ESS, similar to what is documented in our semi-synoptic study. Other/Unknown Material Arctic East Siberian Sea Ice laptev Laptev Sea lena river permafrost Phytoplankton Sea ice Copernicus Publications: E-Journals Arctic East Siberian Sea ENVELOPE(166.000,166.000,74.000,74.000) Laptev Sea Pacific Ocean Science 13 5 735 748 |
institution |
Open Polar |
collection |
Copernicus Publications: E-Journals |
op_collection_id |
ftcopernicus |
language |
English |
description |
Recent Arctic studies suggest that sea ice decline and permafrost thawing will affect phytoplankton dynamics and stimulate heterotrophic communities. However, in what way the plankton composition will change as the warming proceeds remains elusive. Here we investigate the chemical signature of the plankton-dominated fraction of particulate organic matter (POM) collected along the Siberian Shelf. POM (> 10 µm) samples were analysed using molecular biomarkers (CuO oxidation and IP 25 ) and dual-carbon isotopes ( δ 13 C and Δ 14 C). In addition, surface water chemical properties were integrated with the POM (> 10 µm) dataset to understand the link between plankton composition and environmental conditions. δ 13 C and Δ 14 C exhibited a large variability in the POM (> 10 µm) distribution while the content of terrestrial biomarkers in the POM was negligible. In the Laptev Sea (LS), δ 13 C and Δ 14 C of POM (> 10 µm) suggested a heterotrophic environment in which dissolved organic carbon (DOC) from the Lena River was the primary source of metabolisable carbon. Within the Lena plume, terrestrial DOC probably became part of the food web via bacteria uptake and subsequently transferred to relatively other heterotrophic communities (e.g. dinoflagellates). Moving eastwards toward the sea-ice-dominated East Siberian Sea (ESS), the system became progressively more autotrophic. Comparison between δ 13 C of POM (> 10 µm) samples and CO 2 aq concentrations revealed that the carbon isotope fractionation increased moving towards the easternmost and most productive stations. In a warming scenario characterised by enhanced terrestrial DOC release (thawing permafrost) and progressive sea ice decline, heterotrophic conditions might persist in the LS while the nutrient-rich Pacific inflow will likely stimulate greater primary productivity in the ESS. The contrasting trophic conditions will result in a sharp gradient in δ 13 C between the LS and ESS, similar to what is documented in our semi-synoptic study. |
format |
Other/Unknown Material |
author |
Tesi, Tommaso Geibel, Marc C. Pearce, Christof Panova, Elena Vonk, Jorien E. Karlsson, Emma Salvado, Joan A. Kruså, Martin Bröder, Lisa Humborg, Christoph Semiletov, Igor Gustafsson, Örjan |
spellingShingle |
Tesi, Tommaso Geibel, Marc C. Pearce, Christof Panova, Elena Vonk, Jorien E. Karlsson, Emma Salvado, Joan A. Kruså, Martin Bröder, Lisa Humborg, Christoph Semiletov, Igor Gustafsson, Örjan Carbon geochemistry of plankton-dominated samples in the Laptev and East Siberian shelves: contrasts in suspended particle composition |
author_facet |
Tesi, Tommaso Geibel, Marc C. Pearce, Christof Panova, Elena Vonk, Jorien E. Karlsson, Emma Salvado, Joan A. Kruså, Martin Bröder, Lisa Humborg, Christoph Semiletov, Igor Gustafsson, Örjan |
author_sort |
Tesi, Tommaso |
title |
Carbon geochemistry of plankton-dominated samples in the Laptev and East Siberian shelves: contrasts in suspended particle composition |
title_short |
Carbon geochemistry of plankton-dominated samples in the Laptev and East Siberian shelves: contrasts in suspended particle composition |
title_full |
Carbon geochemistry of plankton-dominated samples in the Laptev and East Siberian shelves: contrasts in suspended particle composition |
title_fullStr |
Carbon geochemistry of plankton-dominated samples in the Laptev and East Siberian shelves: contrasts in suspended particle composition |
title_full_unstemmed |
Carbon geochemistry of plankton-dominated samples in the Laptev and East Siberian shelves: contrasts in suspended particle composition |
title_sort |
carbon geochemistry of plankton-dominated samples in the laptev and east siberian shelves: contrasts in suspended particle composition |
publishDate |
2018 |
url |
https://doi.org/10.5194/os-13-735-2017 https://os.copernicus.org/articles/13/735/2017/ |
long_lat |
ENVELOPE(166.000,166.000,74.000,74.000) |
geographic |
Arctic East Siberian Sea Laptev Sea Pacific |
geographic_facet |
Arctic East Siberian Sea Laptev Sea Pacific |
genre |
Arctic East Siberian Sea Ice laptev Laptev Sea lena river permafrost Phytoplankton Sea ice |
genre_facet |
Arctic East Siberian Sea Ice laptev Laptev Sea lena river permafrost Phytoplankton Sea ice |
op_source |
eISSN: 1812-0792 |
op_relation |
info:eu-repo/grantAgreement/EC/FP7/328049 info:eu-repo/grantAgreement/EC/FP7/300259 doi:10.5194/os-13-735-2017 https://os.copernicus.org/articles/13/735/2017/ |
op_rights |
info:eu-repo/semantics/openAccess |
op_doi |
https://doi.org/10.5194/os-13-735-2017 |
container_title |
Ocean Science |
container_volume |
13 |
container_issue |
5 |
container_start_page |
735 |
op_container_end_page |
748 |
_version_ |
1766346233671057408 |