Sabiia Seb
PortuguêsEspañolEnglish
Embrapa
        Busca avançada

Botão Atualizar


Botão Atualizar

Registro completo
Provedor de dados:  ArchiMer
País:  France
Título:  Nitrogen fixation in the eastern Atlantic reaches similar levels in the Southern and Northern Hemisphere
Autores:  Fonseca-batista, Debany
Dehairs, Frank
Riou, Virginie
Fripiat, Francois
Elskens, Marc
Deman, Florian
Brion, Natacha
Queroue, Fabien
Bode, Maya
Auel, Holger
Data:  2017-01
Ano:  2017
Palavras-chave:  Nitrogen fixation
Atlantic Ocean
Primary production
Resumo:  Euphotic layer dinitrogen (N-2) fixation and primary production (PP) were measured in the eastern Atlantic Ocean (38 degrees N-21 degrees S) using N-15(2) and C-13 bicarbonate tracer incubations. This region is influenced by Saharan dust deposition and waters with low nitrogen to phosphorus (N/P) ratios originating from the Subantarctic and the Benguela upwelling system. Depth-integrated rates of N-2 fixation in the north (0 degrees N-38 degrees N) ranged from 59 to 370 mu mol N m(-2) d(-1), with the maximal value at 19 degrees N under the influence of the northwest African upwelling. Diazotrophic activity in the south (0 degrees S-21 degrees S), though slightly lower, was surprisingly close to observations in the north, with values ranging from 47 to 119 mu mol N m(-2) d(-1). Our North Atlantic N-2 fixation rates correlate well with dust deposition, while those in the South Atlantic correlate strongly with excess phosphate relative to nitrate. There, the necessary iron is assumed to be supplied from the Benguela upwelling system. When converting N-2 fixation to carbon uptake using a Redfield ratio (6.6), we find that N-2 fixation may support up to 9% of PP in the subtropical North Atlantic (20 degrees N-38 degrees N), 5% in the tropical North Atlantic (0 degrees N-20 degrees N), and 1% of PP in the South Atlantic (0 degrees S-21 degrees S). Combining our data with published data sets, we estimate an annual N input of 27.610 Tg N yr(-1) over the open Atlantic Ocean, 11% of which enters the region between 20 degrees N and 50 degrees N, 71% between 20 degrees N and 10 degrees S, and 18% between 10 degrees N and 45 degrees S.
Tipo:  Text
Idioma:  Inglês
Identificador:  https://archimer.ifremer.fr/doc/00379/49009/49451.pdf

https://archimer.ifremer.fr/doc/00379/49009/49452.pdf

https://archimer.ifremer.fr/doc/00379/49009/49453.xlsx

https://archimer.ifremer.fr/doc/00379/49009/49454.xlsx

DOI:10.1002/2016JC012335

https://archimer.ifremer.fr/doc/00379/49009/
Editor:  Amer Geophysical Union
Formato:  application/pdf
Fonte:  Journal Of Geophysical Research-oceans (2169-9275) (Amer Geophysical Union), 2017-01 , Vol. 122 , N. 1 , P. 587-601
Direitos:  2016. American Geophysical Union. All Rights Reserved.

info:eu-repo/semantics/openAccess

restricted use
Fechar
 

Empresa Brasileira de Pesquisa Agropecuária - Embrapa
Todos os direitos reservados, conforme Lei n° 9.610
Política de Privacidade
Área restrita

Embrapa
Parque Estação Biológica - PqEB s/n°
Brasília, DF - Brasil - CEP 70770-901
Fone: (61) 3448-4433 - Fax: (61) 3448-4890 / 3448-4891 SAC: https://www.embrapa.br/fale-conosco

Valid HTML 4.01 Transitional