Dissolved organic matter and its utilisation by bacteria during spring in the Southern Ocean
Concentrations of dissolved organic carbon (DOC) and nitrogen (DON) were measured during early austral Spring 1992 at a number of stations along the 6°W meridian between 47° and 60°S. This included the Polar Front in the north, the zone of melting sea-ice in the south, and waters of the Antarctic Ci...
Published in: | Deep Sea Research Part II: Topical Studies in Oceanography |
---|---|
Main Authors: | , , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
Elsevier
1997
|
Subjects: | |
Online Access: | https://oceanrep.geomar.de/id/eprint/1339/ https://oceanrep.geomar.de/id/eprint/1339/1/1-s2.0-S0967064596000719-main.pdf https://doi.org/10.1016/S0967-0645(96)00071-9 |
id |
ftoceanrep:oai:oceanrep.geomar.de:1339 |
---|---|
record_format |
openpolar |
spelling |
ftoceanrep:oai:oceanrep.geomar.de:1339 2023-05-15T13:48:43+02:00 Dissolved organic matter and its utilisation by bacteria during spring in the Southern Ocean Kähler, Paul Bjoernsen, P.K. Lochte, Karin Antia, Avan 1997 text https://oceanrep.geomar.de/id/eprint/1339/ https://oceanrep.geomar.de/id/eprint/1339/1/1-s2.0-S0967064596000719-main.pdf https://doi.org/10.1016/S0967-0645(96)00071-9 en eng Elsevier https://oceanrep.geomar.de/id/eprint/1339/1/1-s2.0-S0967064596000719-main.pdf Kähler, P., Bjoernsen, P. K., Lochte, K. and Antia, A. (1997) Dissolved organic matter and its utilisation by bacteria during spring in the Southern Ocean. Deep-Sea Research Part II-Topical Studies in Oceanography, 44 (1-2). pp. 341-354. DOI 10.1016/S0967-0645(96)00071-9 <https://doi.org/10.1016/S0967-0645%2896%2900071-9>. doi:10.1016/S0967-0645(96)00071-9 info:eu-repo/semantics/restrictedAccess Article PeerReviewed 1997 ftoceanrep https://doi.org/10.1016/S0967-0645(96)00071-9 2023-04-07T14:43:52Z Concentrations of dissolved organic carbon (DOC) and nitrogen (DON) were measured during early austral Spring 1992 at a number of stations along the 6°W meridian between 47° and 60°S. This included the Polar Front in the north, the zone of melting sea-ice in the south, and waters of the Antarctic Circumpolar Current in between. Concentrations of DOC were low in deep water (34–38 μM) with generally similar or slightly higher values in the surface mixed layer (38–55 μM). DOC:DON ratios are wider in surface water than in deep water, i.e. surface accumulations contain relatively C-rich dissolved organic matter. The highly variable distribution of the surface DOC was not related to hydrographic or biotic features (fronts, plankton development) indicating the lability and transient occurrence of this material. Growth rates of bacteria were determined in subsamples from 51 0.8-μm-filtered batches of seawater incubated in the dark at in-situ temperature. Thymidine and leucine uptake and bacterial biomass change as well as changes in dissolved organic carbon in the batches, and oxygen consumption in parallel incubations correlated linearly over 2 weeks of incubation which allowed extrapolation to in-situ conditions. Bacterial growth in these experiments depended strongly on the amount of initial DOC. Growth in water from greater depth (1000 m) containing 38 μM DOC was minimal, as were DOC-decrease and oxygen consumption. Higher rates were observed in surface water slightly enriched with DOC, and highest rates in surface water amended with DOC-rich melted sea ice. Bacterial growth efficiencies (biomass C-increase vs DOC consumed) were about 30%. The experiments showed that at least 40–60% of the DOC in excess of deep water concentrations was available to bacteria. Article in Journal/Newspaper Antarc* Antarctic Sea ice Southern Ocean OceanRep (GEOMAR Helmholtz Centre für Ocean Research Kiel) Antarctic Austral Southern Ocean The Antarctic Deep Sea Research Part II: Topical Studies in Oceanography 44 1-2 341 353 |
institution |
Open Polar |
collection |
OceanRep (GEOMAR Helmholtz Centre für Ocean Research Kiel) |
op_collection_id |
ftoceanrep |
language |
English |
description |
Concentrations of dissolved organic carbon (DOC) and nitrogen (DON) were measured during early austral Spring 1992 at a number of stations along the 6°W meridian between 47° and 60°S. This included the Polar Front in the north, the zone of melting sea-ice in the south, and waters of the Antarctic Circumpolar Current in between. Concentrations of DOC were low in deep water (34–38 μM) with generally similar or slightly higher values in the surface mixed layer (38–55 μM). DOC:DON ratios are wider in surface water than in deep water, i.e. surface accumulations contain relatively C-rich dissolved organic matter. The highly variable distribution of the surface DOC was not related to hydrographic or biotic features (fronts, plankton development) indicating the lability and transient occurrence of this material. Growth rates of bacteria were determined in subsamples from 51 0.8-μm-filtered batches of seawater incubated in the dark at in-situ temperature. Thymidine and leucine uptake and bacterial biomass change as well as changes in dissolved organic carbon in the batches, and oxygen consumption in parallel incubations correlated linearly over 2 weeks of incubation which allowed extrapolation to in-situ conditions. Bacterial growth in these experiments depended strongly on the amount of initial DOC. Growth in water from greater depth (1000 m) containing 38 μM DOC was minimal, as were DOC-decrease and oxygen consumption. Higher rates were observed in surface water slightly enriched with DOC, and highest rates in surface water amended with DOC-rich melted sea ice. Bacterial growth efficiencies (biomass C-increase vs DOC consumed) were about 30%. The experiments showed that at least 40–60% of the DOC in excess of deep water concentrations was available to bacteria. |
format |
Article in Journal/Newspaper |
author |
Kähler, Paul Bjoernsen, P.K. Lochte, Karin Antia, Avan |
spellingShingle |
Kähler, Paul Bjoernsen, P.K. Lochte, Karin Antia, Avan Dissolved organic matter and its utilisation by bacteria during spring in the Southern Ocean |
author_facet |
Kähler, Paul Bjoernsen, P.K. Lochte, Karin Antia, Avan |
author_sort |
Kähler, Paul |
title |
Dissolved organic matter and its utilisation by bacteria during spring in the Southern Ocean |
title_short |
Dissolved organic matter and its utilisation by bacteria during spring in the Southern Ocean |
title_full |
Dissolved organic matter and its utilisation by bacteria during spring in the Southern Ocean |
title_fullStr |
Dissolved organic matter and its utilisation by bacteria during spring in the Southern Ocean |
title_full_unstemmed |
Dissolved organic matter and its utilisation by bacteria during spring in the Southern Ocean |
title_sort |
dissolved organic matter and its utilisation by bacteria during spring in the southern ocean |
publisher |
Elsevier |
publishDate |
1997 |
url |
https://oceanrep.geomar.de/id/eprint/1339/ https://oceanrep.geomar.de/id/eprint/1339/1/1-s2.0-S0967064596000719-main.pdf https://doi.org/10.1016/S0967-0645(96)00071-9 |
geographic |
Antarctic Austral Southern Ocean The Antarctic |
geographic_facet |
Antarctic Austral Southern Ocean The Antarctic |
genre |
Antarc* Antarctic Sea ice Southern Ocean |
genre_facet |
Antarc* Antarctic Sea ice Southern Ocean |
op_relation |
https://oceanrep.geomar.de/id/eprint/1339/1/1-s2.0-S0967064596000719-main.pdf Kähler, P., Bjoernsen, P. K., Lochte, K. and Antia, A. (1997) Dissolved organic matter and its utilisation by bacteria during spring in the Southern Ocean. Deep-Sea Research Part II-Topical Studies in Oceanography, 44 (1-2). pp. 341-354. DOI 10.1016/S0967-0645(96)00071-9 <https://doi.org/10.1016/S0967-0645%2896%2900071-9>. doi:10.1016/S0967-0645(96)00071-9 |
op_rights |
info:eu-repo/semantics/restrictedAccess |
op_doi |
https://doi.org/10.1016/S0967-0645(96)00071-9 |
container_title |
Deep Sea Research Part II: Topical Studies in Oceanography |
container_volume |
44 |
container_issue |
1-2 |
container_start_page |
341 |
op_container_end_page |
353 |
_version_ |
1766249623593156608 |