Dissolved greenhouse gases (nitrous oxide and methane) associated with the naturally iron-fertilized Kerguelen region (KEOPS 2 cruise) in the Southern Ocean
The concentrations of greenhouse gases (GHGs), such as nitrous oxide (N 2 O) and methane (CH 4 ), were measured in the Kerguelen Plateau region (KPR). The KPR is affected by an annual microalgal bloom caused by natural iron fertilization, and this may stimulate the microbes involved in GHG cycling....
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ftdoajarticles:oai:doaj.org/article:71558afcf0ad403899d4be9dcad6fe56 2023-05-15T17:02:05+02:00 Dissolved greenhouse gases (nitrous oxide and methane) associated with the naturally iron-fertilized Kerguelen region (KEOPS 2 cruise) in the Southern Ocean L. Farías L. Florez-Leiva V. Besoain G. Sarthou C. Fernández 2015-03-01T00:00:00Z https://doi.org/10.5194/bg-12-1925-2015 https://doaj.org/article/71558afcf0ad403899d4be9dcad6fe56 EN eng Copernicus Publications http://www.biogeosciences.net/12/1925/2015/bg-12-1925-2015.pdf https://doaj.org/toc/1726-4170 https://doaj.org/toc/1726-4189 1726-4170 1726-4189 doi:10.5194/bg-12-1925-2015 https://doaj.org/article/71558afcf0ad403899d4be9dcad6fe56 Biogeosciences, Vol 12, Iss 6, Pp 1925-1940 (2015) Ecology QH540-549.5 Life QH501-531 Geology QE1-996.5 article 2015 ftdoajarticles https://doi.org/10.5194/bg-12-1925-2015 2022-12-31T16:30:31Z The concentrations of greenhouse gases (GHGs), such as nitrous oxide (N 2 O) and methane (CH 4 ), were measured in the Kerguelen Plateau region (KPR). The KPR is affected by an annual microalgal bloom caused by natural iron fertilization, and this may stimulate the microbes involved in GHG cycling. This study was carried out during the KEOPS 2 cruise during the austral spring of 2011. Oceanographic variables, including N 2 O and CH 4 , were sampled (from the surface to 500 m depth) in two transects along and across the KRP, the north–south (TNS) transect (46°–51° S, ~ 72° E) and the east–west (TEW) transect (66°–75° E, ~ 48.3° S), both associated with the presence of a plateau, polar front (PF) and other mesoscale features. The TEW presented N 2 O levels ranging from equilibrium (105%) to slightly supersaturated (120%) with respect to the atmosphere, whereas CH 4 levels fluctuated dramatically, being highly supersaturated (120–970%) in areas close to the coastal waters of the Kerguelen Islands and in the PF. The TNS showed a more homogenous distribution for both gases, with N 2 O and CH 4 levels ranging from 88 to 171% and 45 to 666% saturation, respectively. Surface CH 4 peaked at southeastern stations of the KPR (A3 stations), where a phytoplankton bloom was observed. Both gases responded significantly, but in contrasting ways (CH 4 accumulation and N 2 O depletion), to the patchy distribution of chlorophyll a . This seems to be associated to the supply of iron from various sources. Air–sea fluxes for N 2 O (from −10.5 to 8.65, mean 1.25 ± 4.04 μmol m −2 d −1 ) and for CH 4 (from 0.32 to 38.1, mean 10.01 ± 9.97 μmol −2 d −1 ) indicated that the KPR is both a sink and a source for N 2 O, as well as a considerable and variable source of CH 4 . This appears to be associated with biological factors, as well as the transport of water masses enriched with Fe and CH 4 from the coastal area of the Kerguelen Islands. These previously unreported results for the Southern Ocean suggest an intense microbial CH 4 production ... Article in Journal/Newspaper Kerguelen Islands Southern Ocean Directory of Open Access Journals: DOAJ Articles Southern Ocean Austral Kerguelen Kerguelen Islands Biogeosciences 12 6 1925 1940 |
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Open Polar |
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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 |
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Ecology QH540-549.5 Life QH501-531 Geology QE1-996.5 L. Farías L. Florez-Leiva V. Besoain G. Sarthou C. Fernández Dissolved greenhouse gases (nitrous oxide and methane) associated with the naturally iron-fertilized Kerguelen region (KEOPS 2 cruise) in the Southern Ocean |
topic_facet |
Ecology QH540-549.5 Life QH501-531 Geology QE1-996.5 |
description |
The concentrations of greenhouse gases (GHGs), such as nitrous oxide (N 2 O) and methane (CH 4 ), were measured in the Kerguelen Plateau region (KPR). The KPR is affected by an annual microalgal bloom caused by natural iron fertilization, and this may stimulate the microbes involved in GHG cycling. This study was carried out during the KEOPS 2 cruise during the austral spring of 2011. Oceanographic variables, including N 2 O and CH 4 , were sampled (from the surface to 500 m depth) in two transects along and across the KRP, the north–south (TNS) transect (46°–51° S, ~ 72° E) and the east–west (TEW) transect (66°–75° E, ~ 48.3° S), both associated with the presence of a plateau, polar front (PF) and other mesoscale features. The TEW presented N 2 O levels ranging from equilibrium (105%) to slightly supersaturated (120%) with respect to the atmosphere, whereas CH 4 levels fluctuated dramatically, being highly supersaturated (120–970%) in areas close to the coastal waters of the Kerguelen Islands and in the PF. The TNS showed a more homogenous distribution for both gases, with N 2 O and CH 4 levels ranging from 88 to 171% and 45 to 666% saturation, respectively. Surface CH 4 peaked at southeastern stations of the KPR (A3 stations), where a phytoplankton bloom was observed. Both gases responded significantly, but in contrasting ways (CH 4 accumulation and N 2 O depletion), to the patchy distribution of chlorophyll a . This seems to be associated to the supply of iron from various sources. Air–sea fluxes for N 2 O (from −10.5 to 8.65, mean 1.25 ± 4.04 μmol m −2 d −1 ) and for CH 4 (from 0.32 to 38.1, mean 10.01 ± 9.97 μmol −2 d −1 ) indicated that the KPR is both a sink and a source for N 2 O, as well as a considerable and variable source of CH 4 . This appears to be associated with biological factors, as well as the transport of water masses enriched with Fe and CH 4 from the coastal area of the Kerguelen Islands. These previously unreported results for the Southern Ocean suggest an intense microbial CH 4 production ... |
format |
Article in Journal/Newspaper |
author |
L. Farías L. Florez-Leiva V. Besoain G. Sarthou C. Fernández |
author_facet |
L. Farías L. Florez-Leiva V. Besoain G. Sarthou C. Fernández |
author_sort |
L. Farías |
title |
Dissolved greenhouse gases (nitrous oxide and methane) associated with the naturally iron-fertilized Kerguelen region (KEOPS 2 cruise) in the Southern Ocean |
title_short |
Dissolved greenhouse gases (nitrous oxide and methane) associated with the naturally iron-fertilized Kerguelen region (KEOPS 2 cruise) in the Southern Ocean |
title_full |
Dissolved greenhouse gases (nitrous oxide and methane) associated with the naturally iron-fertilized Kerguelen region (KEOPS 2 cruise) in the Southern Ocean |
title_fullStr |
Dissolved greenhouse gases (nitrous oxide and methane) associated with the naturally iron-fertilized Kerguelen region (KEOPS 2 cruise) in the Southern Ocean |
title_full_unstemmed |
Dissolved greenhouse gases (nitrous oxide and methane) associated with the naturally iron-fertilized Kerguelen region (KEOPS 2 cruise) in the Southern Ocean |
title_sort |
dissolved greenhouse gases (nitrous oxide and methane) associated with the naturally iron-fertilized kerguelen region (keops 2 cruise) in the southern ocean |
publisher |
Copernicus Publications |
publishDate |
2015 |
url |
https://doi.org/10.5194/bg-12-1925-2015 https://doaj.org/article/71558afcf0ad403899d4be9dcad6fe56 |
geographic |
Southern Ocean Austral Kerguelen Kerguelen Islands |
geographic_facet |
Southern Ocean Austral Kerguelen Kerguelen Islands |
genre |
Kerguelen Islands Southern Ocean |
genre_facet |
Kerguelen Islands Southern Ocean |
op_source |
Biogeosciences, Vol 12, Iss 6, Pp 1925-1940 (2015) |
op_relation |
http://www.biogeosciences.net/12/1925/2015/bg-12-1925-2015.pdf https://doaj.org/toc/1726-4170 https://doaj.org/toc/1726-4189 1726-4170 1726-4189 doi:10.5194/bg-12-1925-2015 https://doaj.org/article/71558afcf0ad403899d4be9dcad6fe56 |
op_doi |
https://doi.org/10.5194/bg-12-1925-2015 |
container_title |
Biogeosciences |
container_volume |
12 |
container_issue |
6 |
container_start_page |
1925 |
op_container_end_page |
1940 |
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1766055326355816448 |