The bacteria–protist link as a main route of dissolved organic matter across contrasting productivity areas on the Patagonian Shelf

Autores
López Abbate, María Celeste; Garzon Cardona, John Edison; Silva, Ricardo; Molinero, Juan Carlos; Ruiz Etcheverry, Laura Agustina; Martínez, Ana María; Gilabert, Azul Sabina; Lara, Ruben Jose
Año de publicación
2025
Idioma
inglés
Tipo de recurso
artículo
Estado
versión publicada
Descripción
While the sources of dissolved organic matter (DOM) in the open ocean are relatively well identified, its fate due to microbial activity is still evolving. Here, we explored how microbial community structure, growth, and grazing of phytoplankton and heterotrophic bacteria influenced the DOM pool and the transformation of its fluorescent fraction. Dilution experiments were performed during the productive season on the Patagonian Shelf (SW Atlantic Ocean), a region of intense biological activity, with peak productivity observed at the shelf break front. Although phytoplankton biomass was higher than that of bacteria, protists selectively preyed on the faster-growing bacterial population, denoting trophic specificity of grazers. High trophic coupling was suggested by the biomass distribution of protistan consumers and their prey, which predominantly exhibited an inverted trophic pyramid structure. An exception to this pattern was observed at the highly productive shelf break front, where a traditional bottom-heavy pyramid emerged, indicating that most phytoplankton evaded protist predation despite evidence of herbivory. Bacterial consumption of DOM appeared uncoupled from its total amount but was influenced by DOM complexity, while the bacterial production of humic-like substances from protistan plankton precursors observed in most experiments highlighted a potential pathway for carbon sequestration. Protistan grazers also significantly influenced DOM dynamics by scaling their DOM contribution in response to the intensity of grazing on heterotrophic bacteria, regardless of productivity levels. This effect likely arises from reducing the number of active DOM-consuming bacteria and by providing egestion DOM compounds. At the onset of the productive season, high bacterial growth rates stimulate protistan grazing, which serves as a link between bacterial biomass and higher trophic levels. However, as grazing pressure increases, protists can also contribute to the accumulation of a fraction of DOM.
Fil: López Abbate, María Celeste. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; Argentina
Fil: Garzon Cardona, John Edison. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; Argentina. Universidad Nacional del Sur. Departamento de Química; Argentina
Fil: Silva, Ricardo. Instituto Nacional de Investigaciones y Desarrollo Pesquero; Argentina
Fil: Molinero, Juan Carlos. Institut de Recherche Pour Le Developpement.; Francia
Fil: Ruiz Etcheverry, Laura Agustina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Centro de Investigaciones del Mar y la Atmósfera. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Centro de Investigaciones del Mar y la Atmósfera; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Ciencias de la Atmósfera y los Océanos; Argentina. Instituto Franco-Argentino sobre Estudios del Clima y sus Impactos; Argentina
Fil: Martínez, Ana María. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Química del Sur. Universidad Nacional del Sur. Departamento de Química. Instituto de Química del Sur; Argentina
Fil: Gilabert, Azul Sabina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; Argentina. Universidad Nacional del Sur. Departamento de Geografía y Turismo; Argentina
Fil: Lara, Ruben Jose. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; Argentina
Materia
DISSOLVED ORGANIC MATTER
PATAGONIAN SHELF
BACTERIA
PROTISTS
Nivel de accesibilidad
acceso abierto
Condiciones de uso
https://creativecommons.org/licenses/by/2.5/ar/
Repositorio
CONICET Digital (CONICET)
Institución
Consejo Nacional de Investigaciones Científicas y Técnicas
OAI Identificador
oai:ri.conicet.gov.ar:11336/267655
Acceder
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oai_identifier_str oai:ri.conicet.gov.ar:11336/267655
network_acronym_str CONICETDig
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network_name_str CONICET Digital (CONICET)
spelling The bacteria–protist link as a main route of dissolved organic matter across contrasting productivity areas on the Patagonian ShelfLópez Abbate, María CelesteGarzon Cardona, John EdisonSilva, RicardoMolinero, Juan CarlosRuiz Etcheverry, Laura AgustinaMartínez, Ana MaríaGilabert, Azul SabinaLara, Ruben JoseDISSOLVED ORGANIC MATTERPATAGONIAN SHELFBACTERIAPROTISTShttps://purl.org/becyt/ford/1.5https://purl.org/becyt/ford/1While the sources of dissolved organic matter (DOM) in the open ocean are relatively well identified, its fate due to microbial activity is still evolving. Here, we explored how microbial community structure, growth, and grazing of phytoplankton and heterotrophic bacteria influenced the DOM pool and the transformation of its fluorescent fraction. Dilution experiments were performed during the productive season on the Patagonian Shelf (SW Atlantic Ocean), a region of intense biological activity, with peak productivity observed at the shelf break front. Although phytoplankton biomass was higher than that of bacteria, protists selectively preyed on the faster-growing bacterial population, denoting trophic specificity of grazers. High trophic coupling was suggested by the biomass distribution of protistan consumers and their prey, which predominantly exhibited an inverted trophic pyramid structure. An exception to this pattern was observed at the highly productive shelf break front, where a traditional bottom-heavy pyramid emerged, indicating that most phytoplankton evaded protist predation despite evidence of herbivory. Bacterial consumption of DOM appeared uncoupled from its total amount but was influenced by DOM complexity, while the bacterial production of humic-like substances from protistan plankton precursors observed in most experiments highlighted a potential pathway for carbon sequestration. Protistan grazers also significantly influenced DOM dynamics by scaling their DOM contribution in response to the intensity of grazing on heterotrophic bacteria, regardless of productivity levels. This effect likely arises from reducing the number of active DOM-consuming bacteria and by providing egestion DOM compounds. At the onset of the productive season, high bacterial growth rates stimulate protistan grazing, which serves as a link between bacterial biomass and higher trophic levels. However, as grazing pressure increases, protists can also contribute to the accumulation of a fraction of DOM.Fil: López Abbate, María Celeste. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; ArgentinaFil: Garzon Cardona, John Edison. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; Argentina. Universidad Nacional del Sur. Departamento de Química; ArgentinaFil: Silva, Ricardo. Instituto Nacional de Investigaciones y Desarrollo Pesquero; ArgentinaFil: Molinero, Juan Carlos. Institut de Recherche Pour Le Developpement.; FranciaFil: Ruiz Etcheverry, Laura Agustina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Centro de Investigaciones del Mar y la Atmósfera. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Centro de Investigaciones del Mar y la Atmósfera; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Ciencias de la Atmósfera y los Océanos; Argentina. Instituto Franco-Argentino sobre Estudios del Clima y sus Impactos; ArgentinaFil: Martínez, Ana María. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Química del Sur. Universidad Nacional del Sur. Departamento de Química. Instituto de Química del Sur; ArgentinaFil: Gilabert, Azul Sabina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; Argentina. Universidad Nacional del Sur. Departamento de Geografía y Turismo; ArgentinaFil: Lara, Ruben Jose. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; ArgentinaCopernicus Publications2025-05info:eu-repo/semantics/articleinfo:eu-repo/semantics/publishedVersionhttp://purl.org/coar/resource_type/c_6501info:ar-repo/semantics/articuloapplication/pdfapplication/pdfapplication/pdfhttp://hdl.handle.net/11336/267655López Abbate, María Celeste; Garzon Cardona, John Edison; Silva, Ricardo; Molinero, Juan Carlos; Ruiz Etcheverry, Laura Agustina; et al.; The bacteria–protist link as a main route of dissolved organic matter across contrasting productivity areas on the Patagonian Shelf; Copernicus Publications; Biogeosciences; 22; 10; 5-2025; 2309-23251726-4189CONICET DigitalCONICETenginfo:eu-repo/semantics/altIdentifier/url/https://bg.copernicus.org/articles/22/2309/2025/info:eu-repo/semantics/altIdentifier/doi/10.5194/bg-22-2309-2025info:eu-repo/semantics/openAccesshttps://creativecommons.org/licenses/by/2.5/ar/reponame:CONICET Digital (CONICET)instname:Consejo Nacional de Investigaciones Científicas y Técnicas2025-10-15T14:51:03Zoai:ri.conicet.gov.ar:11336/267655instacron:CONICETInstitucionalhttp://ri.conicet.gov.ar/Organismo científico-tecnológicoNo correspondehttp://ri.conicet.gov.ar/oai/requestdasensio@conicet.gov.ar; lcarlino@conicet.gov.arArgentinaNo correspondeNo correspondeNo correspondeopendoar:34982025-10-15 14:51:03.313CONICET Digital (CONICET) - Consejo Nacional de Investigaciones Científicas y Técnicasfalse
dc.title.none.fl_str_mv The bacteria–protist link as a main route of dissolved organic matter across contrasting productivity areas on the Patagonian Shelf
title The bacteria–protist link as a main route of dissolved organic matter across contrasting productivity areas on the Patagonian Shelf
spellingShingle The bacteria–protist link as a main route of dissolved organic matter across contrasting productivity areas on the Patagonian Shelf
López Abbate, María Celeste
DISSOLVED ORGANIC MATTER
PATAGONIAN SHELF
BACTERIA
PROTISTS
title_short The bacteria–protist link as a main route of dissolved organic matter across contrasting productivity areas on the Patagonian Shelf
title_full The bacteria–protist link as a main route of dissolved organic matter across contrasting productivity areas on the Patagonian Shelf
title_fullStr The bacteria–protist link as a main route of dissolved organic matter across contrasting productivity areas on the Patagonian Shelf
title_full_unstemmed The bacteria–protist link as a main route of dissolved organic matter across contrasting productivity areas on the Patagonian Shelf
title_sort The bacteria–protist link as a main route of dissolved organic matter across contrasting productivity areas on the Patagonian Shelf
dc.creator.none.fl_str_mv López Abbate, María Celeste
Garzon Cardona, John Edison
Silva, Ricardo
Molinero, Juan Carlos
Ruiz Etcheverry, Laura Agustina
Martínez, Ana María
Gilabert, Azul Sabina
Lara, Ruben Jose
author López Abbate, María Celeste
author_facet López Abbate, María Celeste
Garzon Cardona, John Edison
Silva, Ricardo
Molinero, Juan Carlos
Ruiz Etcheverry, Laura Agustina
Martínez, Ana María
Gilabert, Azul Sabina
Lara, Ruben Jose
author_role author
author2 Garzon Cardona, John Edison
Silva, Ricardo
Molinero, Juan Carlos
Ruiz Etcheverry, Laura Agustina
Martínez, Ana María
Gilabert, Azul Sabina
Lara, Ruben Jose
author2_role author
author
author
author
author
author
author
dc.subject.none.fl_str_mv DISSOLVED ORGANIC MATTER
PATAGONIAN SHELF
BACTERIA
PROTISTS
topic DISSOLVED ORGANIC MATTER
PATAGONIAN SHELF
BACTERIA
PROTISTS
purl_subject.fl_str_mv https://purl.org/becyt/ford/1.5
https://purl.org/becyt/ford/1
dc.description.none.fl_txt_mv While the sources of dissolved organic matter (DOM) in the open ocean are relatively well identified, its fate due to microbial activity is still evolving. Here, we explored how microbial community structure, growth, and grazing of phytoplankton and heterotrophic bacteria influenced the DOM pool and the transformation of its fluorescent fraction. Dilution experiments were performed during the productive season on the Patagonian Shelf (SW Atlantic Ocean), a region of intense biological activity, with peak productivity observed at the shelf break front. Although phytoplankton biomass was higher than that of bacteria, protists selectively preyed on the faster-growing bacterial population, denoting trophic specificity of grazers. High trophic coupling was suggested by the biomass distribution of protistan consumers and their prey, which predominantly exhibited an inverted trophic pyramid structure. An exception to this pattern was observed at the highly productive shelf break front, where a traditional bottom-heavy pyramid emerged, indicating that most phytoplankton evaded protist predation despite evidence of herbivory. Bacterial consumption of DOM appeared uncoupled from its total amount but was influenced by DOM complexity, while the bacterial production of humic-like substances from protistan plankton precursors observed in most experiments highlighted a potential pathway for carbon sequestration. Protistan grazers also significantly influenced DOM dynamics by scaling their DOM contribution in response to the intensity of grazing on heterotrophic bacteria, regardless of productivity levels. This effect likely arises from reducing the number of active DOM-consuming bacteria and by providing egestion DOM compounds. At the onset of the productive season, high bacterial growth rates stimulate protistan grazing, which serves as a link between bacterial biomass and higher trophic levels. However, as grazing pressure increases, protists can also contribute to the accumulation of a fraction of DOM.
Fil: López Abbate, María Celeste. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; Argentina
Fil: Garzon Cardona, John Edison. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; Argentina. Universidad Nacional del Sur. Departamento de Química; Argentina
Fil: Silva, Ricardo. Instituto Nacional de Investigaciones y Desarrollo Pesquero; Argentina
Fil: Molinero, Juan Carlos. Institut de Recherche Pour Le Developpement.; Francia
Fil: Ruiz Etcheverry, Laura Agustina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Centro de Investigaciones del Mar y la Atmósfera. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Centro de Investigaciones del Mar y la Atmósfera; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Ciencias de la Atmósfera y los Océanos; Argentina. Instituto Franco-Argentino sobre Estudios del Clima y sus Impactos; Argentina
Fil: Martínez, Ana María. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Química del Sur. Universidad Nacional del Sur. Departamento de Química. Instituto de Química del Sur; Argentina
Fil: Gilabert, Azul Sabina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; Argentina. Universidad Nacional del Sur. Departamento de Geografía y Turismo; Argentina
Fil: Lara, Ruben Jose. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; Argentina
description While the sources of dissolved organic matter (DOM) in the open ocean are relatively well identified, its fate due to microbial activity is still evolving. Here, we explored how microbial community structure, growth, and grazing of phytoplankton and heterotrophic bacteria influenced the DOM pool and the transformation of its fluorescent fraction. Dilution experiments were performed during the productive season on the Patagonian Shelf (SW Atlantic Ocean), a region of intense biological activity, with peak productivity observed at the shelf break front. Although phytoplankton biomass was higher than that of bacteria, protists selectively preyed on the faster-growing bacterial population, denoting trophic specificity of grazers. High trophic coupling was suggested by the biomass distribution of protistan consumers and their prey, which predominantly exhibited an inverted trophic pyramid structure. An exception to this pattern was observed at the highly productive shelf break front, where a traditional bottom-heavy pyramid emerged, indicating that most phytoplankton evaded protist predation despite evidence of herbivory. Bacterial consumption of DOM appeared uncoupled from its total amount but was influenced by DOM complexity, while the bacterial production of humic-like substances from protistan plankton precursors observed in most experiments highlighted a potential pathway for carbon sequestration. Protistan grazers also significantly influenced DOM dynamics by scaling their DOM contribution in response to the intensity of grazing on heterotrophic bacteria, regardless of productivity levels. This effect likely arises from reducing the number of active DOM-consuming bacteria and by providing egestion DOM compounds. At the onset of the productive season, high bacterial growth rates stimulate protistan grazing, which serves as a link between bacterial biomass and higher trophic levels. However, as grazing pressure increases, protists can also contribute to the accumulation of a fraction of DOM.
publishDate 2025
dc.date.none.fl_str_mv 2025-05
dc.type.none.fl_str_mv info:eu-repo/semantics/article
info:eu-repo/semantics/publishedVersion
http://purl.org/coar/resource_type/c_6501
info:ar-repo/semantics/articulo
format article
status_str publishedVersion
dc.identifier.none.fl_str_mv http://hdl.handle.net/11336/267655
López Abbate, María Celeste; Garzon Cardona, John Edison; Silva, Ricardo; Molinero, Juan Carlos; Ruiz Etcheverry, Laura Agustina; et al.; The bacteria–protist link as a main route of dissolved organic matter across contrasting productivity areas on the Patagonian Shelf; Copernicus Publications; Biogeosciences; 22; 10; 5-2025; 2309-2325
1726-4189
CONICET Digital
CONICET
url http://hdl.handle.net/11336/267655
identifier_str_mv López Abbate, María Celeste; Garzon Cardona, John Edison; Silva, Ricardo; Molinero, Juan Carlos; Ruiz Etcheverry, Laura Agustina; et al.; The bacteria–protist link as a main route of dissolved organic matter across contrasting productivity areas on the Patagonian Shelf; Copernicus Publications; Biogeosciences; 22; 10; 5-2025; 2309-2325
1726-4189
CONICET Digital
CONICET
dc.language.none.fl_str_mv eng
language eng
dc.relation.none.fl_str_mv info:eu-repo/semantics/altIdentifier/url/https://bg.copernicus.org/articles/22/2309/2025/
info:eu-repo/semantics/altIdentifier/doi/10.5194/bg-22-2309-2025
dc.rights.none.fl_str_mv info:eu-repo/semantics/openAccess
https://creativecommons.org/licenses/by/2.5/ar/
eu_rights_str_mv openAccess
rights_invalid_str_mv https://creativecommons.org/licenses/by/2.5/ar/
dc.format.none.fl_str_mv application/pdf
application/pdf
application/pdf
dc.publisher.none.fl_str_mv Copernicus Publications
publisher.none.fl_str_mv Copernicus Publications
dc.source.none.fl_str_mv reponame:CONICET Digital (CONICET)
instname:Consejo Nacional de Investigaciones Científicas y Técnicas
reponame_str CONICET Digital (CONICET)
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instname_str Consejo Nacional de Investigaciones Científicas y Técnicas
repository.name.fl_str_mv CONICET Digital (CONICET) - Consejo Nacional de Investigaciones Científicas y Técnicas
repository.mail.fl_str_mv dasensio@conicet.gov.ar; lcarlino@conicet.gov.ar
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score 13.22299

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