Identification and analysis of low-molecular-weight dissolved organic carbon in subglacial basal ice ecosystems by ion chromatography
Determining the concentration and composition of dissolved organic carbon (DOC) in glacial ecosystems is important for assessments of in situ microbial activity and contributions to wider biogeochemical cycles. Nonetheless, there is limited knowledge of the abundance and character of DOC in basal ic...
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2016
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Online Access: | https://pure.au.dk/portal/da/publications/identification-and-analysis-of-lowmolecularweight-dissolved-organic-carbon-in-subglacial-basal-ice-ecosystems-by-ion-chromatography(605c3e8b-5aee-4611-bd80-378ae49e5a6a).html https://doi.org/10.5194/bg-13-3833-2016 |
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ftuniaarhuspubl:oai:pure.atira.dk:publications/605c3e8b-5aee-4611-bd80-378ae49e5a6a 2023-05-15T13:41:30+02:00 Identification and analysis of low-molecular-weight dissolved organic carbon in subglacial basal ice ecosystems by ion chromatography O'Donnell, Emily C. Wadham, Jemma Lis, Grzegorz Tranter, Martyn Pickard, Amy E. Stibal, Marek Dewsbury, Paul Fitzsimons, Sean 2016-07-01 https://pure.au.dk/portal/da/publications/identification-and-analysis-of-lowmolecularweight-dissolved-organic-carbon-in-subglacial-basal-ice-ecosystems-by-ion-chromatography(605c3e8b-5aee-4611-bd80-378ae49e5a6a).html https://doi.org/10.5194/bg-13-3833-2016 eng eng info:eu-repo/semantics/restrictedAccess O'Donnell , E C , Wadham , J , Lis , G , Tranter , M , Pickard , A E , Stibal , M , Dewsbury , P & Fitzsimons , S 2016 , ' Identification and analysis of low-molecular-weight dissolved organic carbon in subglacial basal ice ecosystems by ion chromatography ' , Biogeosciences , vol. 13 , no. 12 , pp. 3833-3846 . https://doi.org/10.5194/bg-13-3833-2016 article 2016 ftuniaarhuspubl https://doi.org/10.5194/bg-13-3833-2016 2023-01-04T23:56:34Z Determining the concentration and composition of dissolved organic carbon (DOC) in glacial ecosystems is important for assessments of in situ microbial activity and contributions to wider biogeochemical cycles. Nonetheless, there is limited knowledge of the abundance and character of DOC in basal ice and the subglacial environment and a lack of quantitative data on low-molecular-weight (LMW) DOC components, which are believed to be highly bioavailable to microorganisms. We investigated the abundance and composition of DOC in basal ice via a molecular-level DOC analysis. Spectrofluorometry and a novel ion chromatographic method, which has been little utilized in glacial science for LMW-DOC determinations, were employed to identify and quantify the major LMW fractions (free amino acids, carbohydrates, and carboxylic acids) in basal ice from four glaciers, each with a different type of overridden material (i.e. the pre-entrainment sedimentary type such as lacustrine material or palaeosols). Basal ice from Joyce Glacier (Antarctica) was unique in that 98 % of the LMW-DOC was derived from the extremely diverse free amino acid (FAA) pool, comprising 14 FAAs. LMW-DOC concentrations in basal ice were dependent on the bioavailability of the overridden organic carbon (OC), which in turn was influenced by the type of overridden material. Mean LMW-DOC concentrations in basal ice from Russell Glacier (Greenland), Finsterwalderbreen (Svalbard), and Engabreen (Norway) were low (0–417 nM C), attributed to the relatively refractory nature of the OC in the overridden palaeosols and bedrock. In contrast, mean LMW-DOC concentrations were an order of magnitude higher (4430 nM C) in basal ice from Joyce Glacier, a reflection of the high bioavailability of the overridden lacustrine material (> 17 % of the sediment OC comprised extractable carbohydrates, a proxy for bioavailable OC). We find that the overridden material may act as a direct (via abiotic leaching) and indirect (via microbial cycling) source of DOC to the subglacial ... Article in Journal/Newspaper Antarc* Antarctica glacier glacier glacier Greenland Svalbard Aarhus University: Research Engabreen ENVELOPE(13.771,13.771,66.682,66.682) Finsterwalderbreen ENVELOPE(15.273,15.273,77.489,77.489) Greenland Joyce Glacier ENVELOPE(163.700,163.700,-78.017,-78.017) Norway Svalbard Biogeosciences 13 12 3833 3846 |
institution |
Open Polar |
collection |
Aarhus University: Research |
op_collection_id |
ftuniaarhuspubl |
language |
English |
description |
Determining the concentration and composition of dissolved organic carbon (DOC) in glacial ecosystems is important for assessments of in situ microbial activity and contributions to wider biogeochemical cycles. Nonetheless, there is limited knowledge of the abundance and character of DOC in basal ice and the subglacial environment and a lack of quantitative data on low-molecular-weight (LMW) DOC components, which are believed to be highly bioavailable to microorganisms. We investigated the abundance and composition of DOC in basal ice via a molecular-level DOC analysis. Spectrofluorometry and a novel ion chromatographic method, which has been little utilized in glacial science for LMW-DOC determinations, were employed to identify and quantify the major LMW fractions (free amino acids, carbohydrates, and carboxylic acids) in basal ice from four glaciers, each with a different type of overridden material (i.e. the pre-entrainment sedimentary type such as lacustrine material or palaeosols). Basal ice from Joyce Glacier (Antarctica) was unique in that 98 % of the LMW-DOC was derived from the extremely diverse free amino acid (FAA) pool, comprising 14 FAAs. LMW-DOC concentrations in basal ice were dependent on the bioavailability of the overridden organic carbon (OC), which in turn was influenced by the type of overridden material. Mean LMW-DOC concentrations in basal ice from Russell Glacier (Greenland), Finsterwalderbreen (Svalbard), and Engabreen (Norway) were low (0–417 nM C), attributed to the relatively refractory nature of the OC in the overridden palaeosols and bedrock. In contrast, mean LMW-DOC concentrations were an order of magnitude higher (4430 nM C) in basal ice from Joyce Glacier, a reflection of the high bioavailability of the overridden lacustrine material (> 17 % of the sediment OC comprised extractable carbohydrates, a proxy for bioavailable OC). We find that the overridden material may act as a direct (via abiotic leaching) and indirect (via microbial cycling) source of DOC to the subglacial ... |
format |
Article in Journal/Newspaper |
author |
O'Donnell, Emily C. Wadham, Jemma Lis, Grzegorz Tranter, Martyn Pickard, Amy E. Stibal, Marek Dewsbury, Paul Fitzsimons, Sean |
spellingShingle |
O'Donnell, Emily C. Wadham, Jemma Lis, Grzegorz Tranter, Martyn Pickard, Amy E. Stibal, Marek Dewsbury, Paul Fitzsimons, Sean Identification and analysis of low-molecular-weight dissolved organic carbon in subglacial basal ice ecosystems by ion chromatography |
author_facet |
O'Donnell, Emily C. Wadham, Jemma Lis, Grzegorz Tranter, Martyn Pickard, Amy E. Stibal, Marek Dewsbury, Paul Fitzsimons, Sean |
author_sort |
O'Donnell, Emily C. |
title |
Identification and analysis of low-molecular-weight dissolved organic carbon in subglacial basal ice ecosystems by ion chromatography |
title_short |
Identification and analysis of low-molecular-weight dissolved organic carbon in subglacial basal ice ecosystems by ion chromatography |
title_full |
Identification and analysis of low-molecular-weight dissolved organic carbon in subglacial basal ice ecosystems by ion chromatography |
title_fullStr |
Identification and analysis of low-molecular-weight dissolved organic carbon in subglacial basal ice ecosystems by ion chromatography |
title_full_unstemmed |
Identification and analysis of low-molecular-weight dissolved organic carbon in subglacial basal ice ecosystems by ion chromatography |
title_sort |
identification and analysis of low-molecular-weight dissolved organic carbon in subglacial basal ice ecosystems by ion chromatography |
publishDate |
2016 |
url |
https://pure.au.dk/portal/da/publications/identification-and-analysis-of-lowmolecularweight-dissolved-organic-carbon-in-subglacial-basal-ice-ecosystems-by-ion-chromatography(605c3e8b-5aee-4611-bd80-378ae49e5a6a).html https://doi.org/10.5194/bg-13-3833-2016 |
long_lat |
ENVELOPE(13.771,13.771,66.682,66.682) ENVELOPE(15.273,15.273,77.489,77.489) ENVELOPE(163.700,163.700,-78.017,-78.017) |
geographic |
Engabreen Finsterwalderbreen Greenland Joyce Glacier Norway Svalbard |
geographic_facet |
Engabreen Finsterwalderbreen Greenland Joyce Glacier Norway Svalbard |
genre |
Antarc* Antarctica glacier glacier glacier Greenland Svalbard |
genre_facet |
Antarc* Antarctica glacier glacier glacier Greenland Svalbard |
op_source |
O'Donnell , E C , Wadham , J , Lis , G , Tranter , M , Pickard , A E , Stibal , M , Dewsbury , P & Fitzsimons , S 2016 , ' Identification and analysis of low-molecular-weight dissolved organic carbon in subglacial basal ice ecosystems by ion chromatography ' , Biogeosciences , vol. 13 , no. 12 , pp. 3833-3846 . https://doi.org/10.5194/bg-13-3833-2016 |
op_rights |
info:eu-repo/semantics/restrictedAccess |
op_doi |
https://doi.org/10.5194/bg-13-3833-2016 |
container_title |
Biogeosciences |
container_volume |
13 |
container_issue |
12 |
container_start_page |
3833 |
op_container_end_page |
3846 |
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1766151545519341568 |