Effects of iron on the elemental stoichiometry during EIFEX and in the diatoms Fragilariopsis kerguelensis and Chaetoceros dichaeta
The interaction between iron availability and the phytoplankton elemental composition was investigated during the in situ iron fertilization experiment EIFEX and in laboratory experiments with the Southern Ocean diatom species Fragilariopsis kerguelensis and Chaetoceros dichaeta. Contrary to other i...
Published in: | Biogeosciences |
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Language: | English |
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Copernicus Publications (EGU)
2007
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Online Access: | https://oceanrep.geomar.de/id/eprint/2943/ https://oceanrep.geomar.de/id/eprint/2943/1/bg-4-569-2007.pdf http://www.biogeosciences.net/title_and_author_search.html?x=0&y=0&author=hoffmann https://doi.org/10.5194/bg-4-569-2007 |
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ftoceanrep:oai:oceanrep.geomar.de:2943 2024-09-15T18:37:18+00:00 Effects of iron on the elemental stoichiometry during EIFEX and in the diatoms Fragilariopsis kerguelensis and Chaetoceros dichaeta Hoffmann, Linn Peeken, Ilka Lochte, Karin 2007 text https://oceanrep.geomar.de/id/eprint/2943/ https://oceanrep.geomar.de/id/eprint/2943/1/bg-4-569-2007.pdf http://www.biogeosciences.net/title_and_author_search.html?x=0&y=0&author=hoffmann https://doi.org/10.5194/bg-4-569-2007 en eng Copernicus Publications (EGU) https://oceanrep.geomar.de/id/eprint/2943/1/bg-4-569-2007.pdf Hoffmann, L. , Peeken, I. and Lochte, K. (2007) Effects of iron on the elemental stoichiometry during EIFEX and in the diatoms Fragilariopsis kerguelensis and Chaetoceros dichaeta. Open Access Biogeosciences (BG), 4 . pp. 569-579. DOI 10.5194/bg-4-569-2007 <https://doi.org/10.5194/bg-4-569-2007>. doi:10.5194/bg-4-569-2007 info:eu-repo/semantics/openAccess Article PeerReviewed 2007 ftoceanrep https://doi.org/10.5194/bg-4-569-2007 2024-09-04T05:04:40Z The interaction between iron availability and the phytoplankton elemental composition was investigated during the in situ iron fertilization experiment EIFEX and in laboratory experiments with the Southern Ocean diatom species Fragilariopsis kerguelensis and Chaetoceros dichaeta. Contrary to other in situ iron fertilization experiments we observed an increase in the BSi:POC, BSi:PON, and BSi:POP ratios within the iron fertilized patch during EIFEX. This is possibly caused by a relatively stronger increase in diatom abundance compared to other phytoplankton groups and does not necessarily represent the amount of silicification of single diatom cells. In laboratory experiments with F. kerguelensis and C. dichaeta no changes in the POC:PON, PON:POP, and POC:POP ratios were found with changing iron availability in both species. BSi:POC, BSi:PON, and BSi:POP ratios were significantly lower in the high iron treatments compared to the controls. In F. kerguelensis this was caused by a decrease in cellular BSi concentrations and therefore possibly less silicification. In C. dichaeta no change in cellular BSi concentration was found. Here lower BSi:POC, BSi:PON, and BSi:POP ratios were caused by an increase in cellular C, N, and P under high iron conditions. These results indicate that iron limitation does not always increase silicification in diatoms and that changes in the BSi:POC, BSi:PON, and BSi:POP ratios under iron fertilization in the field are caused by a variety of different mechanisms. Our results therefore imply that simple cause-and-effect relationships are not always applicable for modeling of elemental ratios. Article in Journal/Newspaper Southern Ocean OceanRep (GEOMAR Helmholtz Centre für Ocean Research Kiel) Biogeosciences 4 4 569 579 |
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Open Polar |
collection |
OceanRep (GEOMAR Helmholtz Centre für Ocean Research Kiel) |
op_collection_id |
ftoceanrep |
language |
English |
description |
The interaction between iron availability and the phytoplankton elemental composition was investigated during the in situ iron fertilization experiment EIFEX and in laboratory experiments with the Southern Ocean diatom species Fragilariopsis kerguelensis and Chaetoceros dichaeta. Contrary to other in situ iron fertilization experiments we observed an increase in the BSi:POC, BSi:PON, and BSi:POP ratios within the iron fertilized patch during EIFEX. This is possibly caused by a relatively stronger increase in diatom abundance compared to other phytoplankton groups and does not necessarily represent the amount of silicification of single diatom cells. In laboratory experiments with F. kerguelensis and C. dichaeta no changes in the POC:PON, PON:POP, and POC:POP ratios were found with changing iron availability in both species. BSi:POC, BSi:PON, and BSi:POP ratios were significantly lower in the high iron treatments compared to the controls. In F. kerguelensis this was caused by a decrease in cellular BSi concentrations and therefore possibly less silicification. In C. dichaeta no change in cellular BSi concentration was found. Here lower BSi:POC, BSi:PON, and BSi:POP ratios were caused by an increase in cellular C, N, and P under high iron conditions. These results indicate that iron limitation does not always increase silicification in diatoms and that changes in the BSi:POC, BSi:PON, and BSi:POP ratios under iron fertilization in the field are caused by a variety of different mechanisms. Our results therefore imply that simple cause-and-effect relationships are not always applicable for modeling of elemental ratios. |
format |
Article in Journal/Newspaper |
author |
Hoffmann, Linn Peeken, Ilka Lochte, Karin |
spellingShingle |
Hoffmann, Linn Peeken, Ilka Lochte, Karin Effects of iron on the elemental stoichiometry during EIFEX and in the diatoms Fragilariopsis kerguelensis and Chaetoceros dichaeta |
author_facet |
Hoffmann, Linn Peeken, Ilka Lochte, Karin |
author_sort |
Hoffmann, Linn |
title |
Effects of iron on the elemental stoichiometry during EIFEX and in the diatoms Fragilariopsis kerguelensis and Chaetoceros dichaeta |
title_short |
Effects of iron on the elemental stoichiometry during EIFEX and in the diatoms Fragilariopsis kerguelensis and Chaetoceros dichaeta |
title_full |
Effects of iron on the elemental stoichiometry during EIFEX and in the diatoms Fragilariopsis kerguelensis and Chaetoceros dichaeta |
title_fullStr |
Effects of iron on the elemental stoichiometry during EIFEX and in the diatoms Fragilariopsis kerguelensis and Chaetoceros dichaeta |
title_full_unstemmed |
Effects of iron on the elemental stoichiometry during EIFEX and in the diatoms Fragilariopsis kerguelensis and Chaetoceros dichaeta |
title_sort |
effects of iron on the elemental stoichiometry during eifex and in the diatoms fragilariopsis kerguelensis and chaetoceros dichaeta |
publisher |
Copernicus Publications (EGU) |
publishDate |
2007 |
url |
https://oceanrep.geomar.de/id/eprint/2943/ https://oceanrep.geomar.de/id/eprint/2943/1/bg-4-569-2007.pdf http://www.biogeosciences.net/title_and_author_search.html?x=0&y=0&author=hoffmann https://doi.org/10.5194/bg-4-569-2007 |
genre |
Southern Ocean |
genre_facet |
Southern Ocean |
op_relation |
https://oceanrep.geomar.de/id/eprint/2943/1/bg-4-569-2007.pdf Hoffmann, L. , Peeken, I. and Lochte, K. (2007) Effects of iron on the elemental stoichiometry during EIFEX and in the diatoms Fragilariopsis kerguelensis and Chaetoceros dichaeta. Open Access Biogeosciences (BG), 4 . pp. 569-579. DOI 10.5194/bg-4-569-2007 <https://doi.org/10.5194/bg-4-569-2007>. doi:10.5194/bg-4-569-2007 |
op_rights |
info:eu-repo/semantics/openAccess |
op_doi |
https://doi.org/10.5194/bg-4-569-2007 |
container_title |
Biogeosciences |
container_volume |
4 |
container_issue |
4 |
container_start_page |
569 |
op_container_end_page |
579 |
_version_ |
1810481671497056256 |