Microbial food web dynamics during spring phytoplankton blooms in the naturally iron-fertilized Kerguelen area (Southern Ocean)
Microbial food web dynamics were determined during the onset of several spring phytoplankton blooms induced by natural iron fertilization off Kerguelen Island in the Southern Ocean (KEOPS2). The abundances of heterotrophic bacteria and heterotrophic nanoflagellates, bacterial heterotrophic productio...
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ftdoajarticles:oai:doaj.org/article:85104e50435f4594a32939d0a3ec0dbe 2023-05-15T18:25:01+02:00 Microbial food web dynamics during spring phytoplankton blooms in the naturally iron-fertilized Kerguelen area (Southern Ocean) U. Christaki D. Lefèvre C. Georges J. Colombet P. Catala C. Courties T. Sime-Ngando S. Blain I. Obernosterer 2014-12-01T00:00:00Z https://doi.org/10.5194/bg-11-6739-2014 https://doaj.org/article/85104e50435f4594a32939d0a3ec0dbe EN eng Copernicus Publications http://www.biogeosciences.net/11/6739/2014/bg-11-6739-2014.pdf https://doaj.org/toc/1726-4170 https://doaj.org/toc/1726-4189 1726-4170 1726-4189 doi:10.5194/bg-11-6739-2014 https://doaj.org/article/85104e50435f4594a32939d0a3ec0dbe Biogeosciences, Vol 11, Iss 23, Pp 6739-6753 (2014) Ecology QH540-549.5 Life QH501-531 Geology QE1-996.5 article 2014 ftdoajarticles https://doi.org/10.5194/bg-11-6739-2014 2022-12-31T15:52:54Z Microbial food web dynamics were determined during the onset of several spring phytoplankton blooms induced by natural iron fertilization off Kerguelen Island in the Southern Ocean (KEOPS2). The abundances of heterotrophic bacteria and heterotrophic nanoflagellates, bacterial heterotrophic production, bacterial respiration, and bacterial growth efficiency, were consistently higher in surface waters of the iron-fertilized sites than at the reference site in HNLC (high nutrient low chlorophyll) waters. The abundance of virus-like particles remained unchanged, but viral production increased by a factor of 6 in iron-fertilized waters. Bacterial heterotrophic production was significantly related to heterotrophic nanoflagellate abundance and viral production across all sites, with bacterial production explaining about 70 and 85%, respectively, of the variance of each in the mixed layer (ML). Estimated rates of grazing and viral lysis, however, indicated that heterotrophic nanoflagellates accounted for a substantially higher loss of bacterial production (50%) than viruses (11%). Combining these results with rates of primary production and export determined for the study area, a budget for the flow of carbon through the microbial food web and higher trophic levels during the early (KEOPS2) and the late phase (KEOPS1) of the Kerguelen bloom is provided. Article in Journal/Newspaper Southern Ocean Directory of Open Access Journals: DOAJ Articles Kerguelen Kerguelen Island ENVELOPE(69.500,69.500,-49.250,-49.250) Southern Ocean Biogeosciences 11 23 6739 6753 |
institution |
Open Polar |
collection |
Directory of Open Access Journals: DOAJ Articles |
op_collection_id |
ftdoajarticles |
language |
English |
topic |
Ecology QH540-549.5 Life QH501-531 Geology QE1-996.5 |
spellingShingle |
Ecology QH540-549.5 Life QH501-531 Geology QE1-996.5 U. Christaki D. Lefèvre C. Georges J. Colombet P. Catala C. Courties T. Sime-Ngando S. Blain I. Obernosterer Microbial food web dynamics during spring phytoplankton blooms in the naturally iron-fertilized Kerguelen area (Southern Ocean) |
topic_facet |
Ecology QH540-549.5 Life QH501-531 Geology QE1-996.5 |
description |
Microbial food web dynamics were determined during the onset of several spring phytoplankton blooms induced by natural iron fertilization off Kerguelen Island in the Southern Ocean (KEOPS2). The abundances of heterotrophic bacteria and heterotrophic nanoflagellates, bacterial heterotrophic production, bacterial respiration, and bacterial growth efficiency, were consistently higher in surface waters of the iron-fertilized sites than at the reference site in HNLC (high nutrient low chlorophyll) waters. The abundance of virus-like particles remained unchanged, but viral production increased by a factor of 6 in iron-fertilized waters. Bacterial heterotrophic production was significantly related to heterotrophic nanoflagellate abundance and viral production across all sites, with bacterial production explaining about 70 and 85%, respectively, of the variance of each in the mixed layer (ML). Estimated rates of grazing and viral lysis, however, indicated that heterotrophic nanoflagellates accounted for a substantially higher loss of bacterial production (50%) than viruses (11%). Combining these results with rates of primary production and export determined for the study area, a budget for the flow of carbon through the microbial food web and higher trophic levels during the early (KEOPS2) and the late phase (KEOPS1) of the Kerguelen bloom is provided. |
format |
Article in Journal/Newspaper |
author |
U. Christaki D. Lefèvre C. Georges J. Colombet P. Catala C. Courties T. Sime-Ngando S. Blain I. Obernosterer |
author_facet |
U. Christaki D. Lefèvre C. Georges J. Colombet P. Catala C. Courties T. Sime-Ngando S. Blain I. Obernosterer |
author_sort |
U. Christaki |
title |
Microbial food web dynamics during spring phytoplankton blooms in the naturally iron-fertilized Kerguelen area (Southern Ocean) |
title_short |
Microbial food web dynamics during spring phytoplankton blooms in the naturally iron-fertilized Kerguelen area (Southern Ocean) |
title_full |
Microbial food web dynamics during spring phytoplankton blooms in the naturally iron-fertilized Kerguelen area (Southern Ocean) |
title_fullStr |
Microbial food web dynamics during spring phytoplankton blooms in the naturally iron-fertilized Kerguelen area (Southern Ocean) |
title_full_unstemmed |
Microbial food web dynamics during spring phytoplankton blooms in the naturally iron-fertilized Kerguelen area (Southern Ocean) |
title_sort |
microbial food web dynamics during spring phytoplankton blooms in the naturally iron-fertilized kerguelen area (southern ocean) |
publisher |
Copernicus Publications |
publishDate |
2014 |
url |
https://doi.org/10.5194/bg-11-6739-2014 https://doaj.org/article/85104e50435f4594a32939d0a3ec0dbe |
long_lat |
ENVELOPE(69.500,69.500,-49.250,-49.250) |
geographic |
Kerguelen Kerguelen Island Southern Ocean |
geographic_facet |
Kerguelen Kerguelen Island Southern Ocean |
genre |
Southern Ocean |
genre_facet |
Southern Ocean |
op_source |
Biogeosciences, Vol 11, Iss 23, Pp 6739-6753 (2014) |
op_relation |
http://www.biogeosciences.net/11/6739/2014/bg-11-6739-2014.pdf https://doaj.org/toc/1726-4170 https://doaj.org/toc/1726-4189 1726-4170 1726-4189 doi:10.5194/bg-11-6739-2014 https://doaj.org/article/85104e50435f4594a32939d0a3ec0dbe |
op_doi |
https://doi.org/10.5194/bg-11-6739-2014 |
container_title |
Biogeosciences |
container_volume |
11 |
container_issue |
23 |
container_start_page |
6739 |
op_container_end_page |
6753 |
_version_ |
1766206160333963264 |