Changing nutrient stoichiometry affects phytoplankton production, DOP accumulation and dinitrogen fixation – a mesocosm experiment in the eastern tropical North Atlantic
Ocean deoxygenation due to climate change may alter redox-sensitive nutrient cycles in the marine environment. The productive eastern tropical North Atlantic (ETNA) upwelling region may be particularly affected when the relatively moderate oxygen minimum zone (OMZ) deoxygenates further and microbial...
Published in: | Biogeosciences |
---|---|
Main Authors: | , , , , , , , , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
Copernicus Publications (EGU)
2016
|
Subjects: | |
Online Access: | https://oceanrep.geomar.de/id/eprint/29227/ https://oceanrep.geomar.de/id/eprint/29227/1/bg-13-781-2016.pdf https://oceanrep.geomar.de/id/eprint/29227/2/bg-13-781-2016-supplement.pdf https://doi.org/10.5194/bg-13-781-2016 |
id |
ftoceanrep:oai:oceanrep.geomar.de:29227 |
---|---|
record_format |
openpolar |
spelling |
ftoceanrep:oai:oceanrep.geomar.de:29227 2023-05-15T17:31:58+02:00 Changing nutrient stoichiometry affects phytoplankton production, DOP accumulation and dinitrogen fixation – a mesocosm experiment in the eastern tropical North Atlantic Meyer, Judith Löscher, Carolin Neulinger, S. C. Reichel, Anna Loginova, Alexandra N Borchard, Corinna Schmitz, R. A. Hauss, Helena Kiko, Rainer Riebesell, Ulf 2016-02-11 text https://oceanrep.geomar.de/id/eprint/29227/ https://oceanrep.geomar.de/id/eprint/29227/1/bg-13-781-2016.pdf https://oceanrep.geomar.de/id/eprint/29227/2/bg-13-781-2016-supplement.pdf https://doi.org/10.5194/bg-13-781-2016 en eng Copernicus Publications (EGU) https://oceanrep.geomar.de/id/eprint/29227/1/bg-13-781-2016.pdf https://oceanrep.geomar.de/id/eprint/29227/2/bg-13-781-2016-supplement.pdf Meyer, J., Löscher, C., Neulinger, S. C., Reichel, A., Loginova, A. N. , Borchard, C., Schmitz, R. A., Hauss, H. , Kiko, R. and Riebesell, U. (2016) Changing nutrient stoichiometry affects phytoplankton production, DOP accumulation and dinitrogen fixation – a mesocosm experiment in the eastern tropical North Atlantic. Open Access Biogeosciences (BG), 13 . pp. 781-794. DOI 10.5194/bg-13-781-2016 <https://doi.org/10.5194/bg-13-781-2016>. doi:10.5194/bg-13-781-2016 cc_by_3.0 info:eu-repo/semantics/openAccess Article PeerReviewed 2016 ftoceanrep https://doi.org/10.5194/bg-13-781-2016 2023-04-07T15:20:06Z Ocean deoxygenation due to climate change may alter redox-sensitive nutrient cycles in the marine environment. The productive eastern tropical North Atlantic (ETNA) upwelling region may be particularly affected when the relatively moderate oxygen minimum zone (OMZ) deoxygenates further and microbially driven nitrogen (N) loss processes are promoted. Consequently, water masses with a low nitrogen to phosphorus (N : P) ratio could reach the euphotic layer, possibly influencing primary production in those waters. Previous mesocosm studies in the oligotrophic Atlantic Ocean identified nitrate availability as a control of primary production, while a possible co-limitation of nitrate and phosphate could not be ruled out. To better understand the impact of changing N : P ratios on primary production and N2 fixation in the ETNA surface ocean, we conducted land-based mesocosm experiments with natural plankton communities and applied a broad range of N : P ratios (2.67–48). Silicic acid was supplied at 15 µmol L−1 in all mesocosms. We monitored nutrient drawdown, biomass accumulation and nitrogen fixation in response to variable nutrient stoichiometry. Our results confirmed nitrate to be the key factor determining primary production. We found that excess phosphate was channeled through particulate organic matter (POP) into the dissolved organic matter (DOP) pool. In mesocosms with low inorganic phosphate availability, DOP was utilized while N2 fixation increased, suggesting a link between those two processes. Interestingly this observation was most pronounced in mesocosms where nitrate was still available, indicating that bioavailable N does not necessarily suppress N2 fixation. We observed a shift from a mixed cyanobacteria–proteobacteria dominated active diazotrophic community towards a diatom-diazotrophic association of the Richelia-Rhizosolenia symbiosis. We hypothesize that a potential change in nutrient stoichiometry in the ETNA might lead to a general shift within the diazotrophic community, potentially influencing ... Article in Journal/Newspaper North Atlantic OceanRep (GEOMAR Helmholtz Centre für Ocean Research Kiel) Biogeosciences 13 3 781 794 |
institution |
Open Polar |
collection |
OceanRep (GEOMAR Helmholtz Centre für Ocean Research Kiel) |
op_collection_id |
ftoceanrep |
language |
English |
description |
Ocean deoxygenation due to climate change may alter redox-sensitive nutrient cycles in the marine environment. The productive eastern tropical North Atlantic (ETNA) upwelling region may be particularly affected when the relatively moderate oxygen minimum zone (OMZ) deoxygenates further and microbially driven nitrogen (N) loss processes are promoted. Consequently, water masses with a low nitrogen to phosphorus (N : P) ratio could reach the euphotic layer, possibly influencing primary production in those waters. Previous mesocosm studies in the oligotrophic Atlantic Ocean identified nitrate availability as a control of primary production, while a possible co-limitation of nitrate and phosphate could not be ruled out. To better understand the impact of changing N : P ratios on primary production and N2 fixation in the ETNA surface ocean, we conducted land-based mesocosm experiments with natural plankton communities and applied a broad range of N : P ratios (2.67–48). Silicic acid was supplied at 15 µmol L−1 in all mesocosms. We monitored nutrient drawdown, biomass accumulation and nitrogen fixation in response to variable nutrient stoichiometry. Our results confirmed nitrate to be the key factor determining primary production. We found that excess phosphate was channeled through particulate organic matter (POP) into the dissolved organic matter (DOP) pool. In mesocosms with low inorganic phosphate availability, DOP was utilized while N2 fixation increased, suggesting a link between those two processes. Interestingly this observation was most pronounced in mesocosms where nitrate was still available, indicating that bioavailable N does not necessarily suppress N2 fixation. We observed a shift from a mixed cyanobacteria–proteobacteria dominated active diazotrophic community towards a diatom-diazotrophic association of the Richelia-Rhizosolenia symbiosis. We hypothesize that a potential change in nutrient stoichiometry in the ETNA might lead to a general shift within the diazotrophic community, potentially influencing ... |
format |
Article in Journal/Newspaper |
author |
Meyer, Judith Löscher, Carolin Neulinger, S. C. Reichel, Anna Loginova, Alexandra N Borchard, Corinna Schmitz, R. A. Hauss, Helena Kiko, Rainer Riebesell, Ulf |
spellingShingle |
Meyer, Judith Löscher, Carolin Neulinger, S. C. Reichel, Anna Loginova, Alexandra N Borchard, Corinna Schmitz, R. A. Hauss, Helena Kiko, Rainer Riebesell, Ulf Changing nutrient stoichiometry affects phytoplankton production, DOP accumulation and dinitrogen fixation – a mesocosm experiment in the eastern tropical North Atlantic |
author_facet |
Meyer, Judith Löscher, Carolin Neulinger, S. C. Reichel, Anna Loginova, Alexandra N Borchard, Corinna Schmitz, R. A. Hauss, Helena Kiko, Rainer Riebesell, Ulf |
author_sort |
Meyer, Judith |
title |
Changing nutrient stoichiometry affects phytoplankton production, DOP accumulation and dinitrogen fixation – a mesocosm experiment in the eastern tropical North Atlantic |
title_short |
Changing nutrient stoichiometry affects phytoplankton production, DOP accumulation and dinitrogen fixation – a mesocosm experiment in the eastern tropical North Atlantic |
title_full |
Changing nutrient stoichiometry affects phytoplankton production, DOP accumulation and dinitrogen fixation – a mesocosm experiment in the eastern tropical North Atlantic |
title_fullStr |
Changing nutrient stoichiometry affects phytoplankton production, DOP accumulation and dinitrogen fixation – a mesocosm experiment in the eastern tropical North Atlantic |
title_full_unstemmed |
Changing nutrient stoichiometry affects phytoplankton production, DOP accumulation and dinitrogen fixation – a mesocosm experiment in the eastern tropical North Atlantic |
title_sort |
changing nutrient stoichiometry affects phytoplankton production, dop accumulation and dinitrogen fixation – a mesocosm experiment in the eastern tropical north atlantic |
publisher |
Copernicus Publications (EGU) |
publishDate |
2016 |
url |
https://oceanrep.geomar.de/id/eprint/29227/ https://oceanrep.geomar.de/id/eprint/29227/1/bg-13-781-2016.pdf https://oceanrep.geomar.de/id/eprint/29227/2/bg-13-781-2016-supplement.pdf https://doi.org/10.5194/bg-13-781-2016 |
genre |
North Atlantic |
genre_facet |
North Atlantic |
op_relation |
https://oceanrep.geomar.de/id/eprint/29227/1/bg-13-781-2016.pdf https://oceanrep.geomar.de/id/eprint/29227/2/bg-13-781-2016-supplement.pdf Meyer, J., Löscher, C., Neulinger, S. C., Reichel, A., Loginova, A. N. , Borchard, C., Schmitz, R. A., Hauss, H. , Kiko, R. and Riebesell, U. (2016) Changing nutrient stoichiometry affects phytoplankton production, DOP accumulation and dinitrogen fixation – a mesocosm experiment in the eastern tropical North Atlantic. Open Access Biogeosciences (BG), 13 . pp. 781-794. DOI 10.5194/bg-13-781-2016 <https://doi.org/10.5194/bg-13-781-2016>. doi:10.5194/bg-13-781-2016 |
op_rights |
cc_by_3.0 info:eu-repo/semantics/openAccess |
op_doi |
https://doi.org/10.5194/bg-13-781-2016 |
container_title |
Biogeosciences |
container_volume |
13 |
container_issue |
3 |
container_start_page |
781 |
op_container_end_page |
794 |
_version_ |
1766129866600611840 |