Nitrogen fixation changes regulated by upper‐water structure in the South China Sea during the last two glacial cycles
Marine nitrogen fixation contributes to the budget of biologically available N, thus fuels phytoplankton productivity and carbon cycle through biological pump. Modern N‐fixation rates are proved to be constrained by oceanographic condition and nutrient supply to the surface waters. However, the pale...
Published in: | Global Biogeochemical Cycles |
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Main Authors: | , , , , |
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Language: | English |
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American Geophysical Union (AGU)
2019
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Online Access: | https://archimer.ifremer.fr/doc/00509/62061/66237.pdf https://archimer.ifremer.fr/doc/00509/62061/66238.pdf https://archimer.ifremer.fr/doc/00509/62061/66239.xlsx https://archimer.ifremer.fr/doc/00509/62061/66240.xlsx https://archimer.ifremer.fr/doc/00509/62061/66241.xlsx https://archimer.ifremer.fr/doc/00509/62061/66242.xlsx https://doi.org/10.1029/2019GB006262 https://archimer.ifremer.fr/doc/00509/62061/ |
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ftarchimer:oai:archimer.ifremer.fr:62061 2023-05-15T17:35:21+02:00 Nitrogen fixation changes regulated by upper‐water structure in the South China Sea during the last two glacial cycles Li, Chen Jian, Zhimin Jia, Guodong Dang, Haowen Wang, Jianxin 2019-08 application/pdf https://archimer.ifremer.fr/doc/00509/62061/66237.pdf https://archimer.ifremer.fr/doc/00509/62061/66238.pdf https://archimer.ifremer.fr/doc/00509/62061/66239.xlsx https://archimer.ifremer.fr/doc/00509/62061/66240.xlsx https://archimer.ifremer.fr/doc/00509/62061/66241.xlsx https://archimer.ifremer.fr/doc/00509/62061/66242.xlsx https://doi.org/10.1029/2019GB006262 https://archimer.ifremer.fr/doc/00509/62061/ eng eng American Geophysical Union (AGU) https://archimer.ifremer.fr/doc/00509/62061/66237.pdf https://archimer.ifremer.fr/doc/00509/62061/66238.pdf https://archimer.ifremer.fr/doc/00509/62061/66239.xlsx https://archimer.ifremer.fr/doc/00509/62061/66240.xlsx https://archimer.ifremer.fr/doc/00509/62061/66241.xlsx https://archimer.ifremer.fr/doc/00509/62061/66242.xlsx doi:10.1029/2019GB006262 https://archimer.ifremer.fr/doc/00509/62061/ info:eu-repo/semantics/openAccess restricted use Global Biogeochemical Cycles (0886-6236) (American Geophysical Union (AGU)), 2019-08 , Vol. 33 , N. 8 , P. 1010-1025 compound-specific delta N-15 upper water structure bulk sedimentary delta N-15 nitrogen fixation orbital time scale South China Sea text Publication info:eu-repo/semantics/article 2019 ftarchimer https://doi.org/10.1029/2019GB006262 2021-09-23T20:33:14Z Marine nitrogen fixation contributes to the budget of biologically available N, thus fuels phytoplankton productivity and carbon cycle through biological pump. Modern N‐fixation rates are proved to be constrained by oceanographic condition and nutrient supply to the surface waters. However, the paleoceanographic reconstruction of N‐fixation and its regulation mechanism remain highly uncertain in many regions. Here we present records of N‐fixation changes in the South China Sea (SCS) over the past 250,000 years reconstructed by compound‐specific nitrogen isotopes of individual amino acids. The δ15N of source amino acids (δ15NSrc), reflecting the δ15N of the substrate nitrate originating from the subsurface water, is distinctly lower during interglacial periods, indicating intensified N‐fixation during interglacials. The δ15NSrc of the SCS co‐varies with the thermal gradient between surface and subsurface waters, implying a tight link between the upper water structure and N‐fixation. It could be hypothesized that stronger mixing during interglacials enhances the supply of excess phosphorous from the subsurface waters, thus encourages the growth of diazotrophs. Furthermore, records of bulk sediment δ15N with relatively high time resolution show dominant precession cycle, probably related to the nutrient supply from subsurface water driven by summer monsoon and associated upper water structure changes. Similar mechanism controlling N‐fixation is also effective in regions with enough iron supply and low concentrations of nitrogen and phosphorous, like the North Atlantic, supporting that upper water structure can dominate N fixation rates by regulating nutrient stoichiometry supplied to the surface waters. Article in Journal/Newspaper North Atlantic Archimer (Archive Institutionnelle de l'Ifremer - Institut français de recherche pour l'exploitation de la mer) Global Biogeochemical Cycles 33 8 1010 1025 |
institution |
Open Polar |
collection |
Archimer (Archive Institutionnelle de l'Ifremer - Institut français de recherche pour l'exploitation de la mer) |
op_collection_id |
ftarchimer |
language |
English |
topic |
compound-specific delta N-15 upper water structure bulk sedimentary delta N-15 nitrogen fixation orbital time scale South China Sea |
spellingShingle |
compound-specific delta N-15 upper water structure bulk sedimentary delta N-15 nitrogen fixation orbital time scale South China Sea Li, Chen Jian, Zhimin Jia, Guodong Dang, Haowen Wang, Jianxin Nitrogen fixation changes regulated by upper‐water structure in the South China Sea during the last two glacial cycles |
topic_facet |
compound-specific delta N-15 upper water structure bulk sedimentary delta N-15 nitrogen fixation orbital time scale South China Sea |
description |
Marine nitrogen fixation contributes to the budget of biologically available N, thus fuels phytoplankton productivity and carbon cycle through biological pump. Modern N‐fixation rates are proved to be constrained by oceanographic condition and nutrient supply to the surface waters. However, the paleoceanographic reconstruction of N‐fixation and its regulation mechanism remain highly uncertain in many regions. Here we present records of N‐fixation changes in the South China Sea (SCS) over the past 250,000 years reconstructed by compound‐specific nitrogen isotopes of individual amino acids. The δ15N of source amino acids (δ15NSrc), reflecting the δ15N of the substrate nitrate originating from the subsurface water, is distinctly lower during interglacial periods, indicating intensified N‐fixation during interglacials. The δ15NSrc of the SCS co‐varies with the thermal gradient between surface and subsurface waters, implying a tight link between the upper water structure and N‐fixation. It could be hypothesized that stronger mixing during interglacials enhances the supply of excess phosphorous from the subsurface waters, thus encourages the growth of diazotrophs. Furthermore, records of bulk sediment δ15N with relatively high time resolution show dominant precession cycle, probably related to the nutrient supply from subsurface water driven by summer monsoon and associated upper water structure changes. Similar mechanism controlling N‐fixation is also effective in regions with enough iron supply and low concentrations of nitrogen and phosphorous, like the North Atlantic, supporting that upper water structure can dominate N fixation rates by regulating nutrient stoichiometry supplied to the surface waters. |
format |
Article in Journal/Newspaper |
author |
Li, Chen Jian, Zhimin Jia, Guodong Dang, Haowen Wang, Jianxin |
author_facet |
Li, Chen Jian, Zhimin Jia, Guodong Dang, Haowen Wang, Jianxin |
author_sort |
Li, Chen |
title |
Nitrogen fixation changes regulated by upper‐water structure in the South China Sea during the last two glacial cycles |
title_short |
Nitrogen fixation changes regulated by upper‐water structure in the South China Sea during the last two glacial cycles |
title_full |
Nitrogen fixation changes regulated by upper‐water structure in the South China Sea during the last two glacial cycles |
title_fullStr |
Nitrogen fixation changes regulated by upper‐water structure in the South China Sea during the last two glacial cycles |
title_full_unstemmed |
Nitrogen fixation changes regulated by upper‐water structure in the South China Sea during the last two glacial cycles |
title_sort |
nitrogen fixation changes regulated by upper‐water structure in the south china sea during the last two glacial cycles |
publisher |
American Geophysical Union (AGU) |
publishDate |
2019 |
url |
https://archimer.ifremer.fr/doc/00509/62061/66237.pdf https://archimer.ifremer.fr/doc/00509/62061/66238.pdf https://archimer.ifremer.fr/doc/00509/62061/66239.xlsx https://archimer.ifremer.fr/doc/00509/62061/66240.xlsx https://archimer.ifremer.fr/doc/00509/62061/66241.xlsx https://archimer.ifremer.fr/doc/00509/62061/66242.xlsx https://doi.org/10.1029/2019GB006262 https://archimer.ifremer.fr/doc/00509/62061/ |
genre |
North Atlantic |
genre_facet |
North Atlantic |
op_source |
Global Biogeochemical Cycles (0886-6236) (American Geophysical Union (AGU)), 2019-08 , Vol. 33 , N. 8 , P. 1010-1025 |
op_relation |
https://archimer.ifremer.fr/doc/00509/62061/66237.pdf https://archimer.ifremer.fr/doc/00509/62061/66238.pdf https://archimer.ifremer.fr/doc/00509/62061/66239.xlsx https://archimer.ifremer.fr/doc/00509/62061/66240.xlsx https://archimer.ifremer.fr/doc/00509/62061/66241.xlsx https://archimer.ifremer.fr/doc/00509/62061/66242.xlsx doi:10.1029/2019GB006262 https://archimer.ifremer.fr/doc/00509/62061/ |
op_rights |
info:eu-repo/semantics/openAccess restricted use |
op_doi |
https://doi.org/10.1029/2019GB006262 |
container_title |
Global Biogeochemical Cycles |
container_volume |
33 |
container_issue |
8 |
container_start_page |
1010 |
op_container_end_page |
1025 |
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1766134475611176960 |