Zooplankton and Micronekton Active Flux Across the Tropical and Subtropical Atlantic Ocean
Quantification of the actual amount of carbon export to the mesopelagic layer by both zooplankton and micronekton is at present a gap in the knowledge of the biological pump. These organisms perform diel vertical migrations exporting carbon through respiration, excretion, mortality, and egestion dur...
| Main Authors: | , , , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Frontiers Media S.A.
2019-09-01
|
| Series: | Frontiers in Marine Science |
| Subjects: | |
| Online Access: | https://www.frontiersin.org/article/10.3389/fmars.2019.00535/full |
| _version_ | 1819115378115084288 |
|---|---|
| author | Santiago Hernández-León María Pilar Olivar María Luz Fernández de Puelles Antonio Bode Arturo Castellón Cristina López-Pérez Víctor M. Tuset José Ignacio González-Gordillo |
| author_facet | Santiago Hernández-León María Pilar Olivar María Luz Fernández de Puelles Antonio Bode Arturo Castellón Cristina López-Pérez Víctor M. Tuset José Ignacio González-Gordillo |
| author_sort | Santiago Hernández-León |
| collection | DOAJ |
| description | Quantification of the actual amount of carbon export to the mesopelagic layer by both zooplankton and micronekton is at present a gap in the knowledge of the biological pump. These organisms perform diel vertical migrations exporting carbon through respiration, excretion, mortality, and egestion during their residence at depth. The role of zooplankton in active flux is nowadays partially assessed. However, micronekton active flux is scarcely known and only a few studies addressed this downward transport. Even less is known about the capacity of both communities to export carbon in the ocean. Here, we show the results of zooplankton and micronekton active flux across a productivity gradient in the tropical and subtropical Atlantic Ocean. Biomass vertical distribution from the surface up to 800 m depth by day and night was studied during April 2015 in a transect from 9°S to 25°N, covering from the quite oligotrophic zone off Brazil to the meso- and eutrophic areas of the equator, Guinea Dome, and the oceanic upwelling off Northwest Africa. Zooplankton and micronekton migrant biomass was estimated from day and night catches at different layers of the water column using MOCNESS-1 (1 m2 mouth area) and Mesopelagos (35 m2) nets, respectively. Respiratory flux was assessed by measuring the enzymatic activity of the electron transfer system (ETS) of organisms at depth. Results showed a close relationship between migrant biomass and respiratory flux in zooplankton and micronekton as expected. Using a rather conservative 50% of efficiency for the net used to capture micronekton, respiratory flux resulted in similar values for both communities. Gravitational (passive) flux measured using sediment traps increased from the oligotrophic toward the meso- and eutrophic zones. Total active flux (including respiration and estimated mortality, excretion, and gut flux) by zooplankton and micronekton accounted for about 25% of total flux (passive plus active) in oligotrophic zones. Total active flux also increased toward meso- and eutrophic zones, reaching about 80% of total flux and being at least twofold higher than passive flux. These results alert about an important underestimation of the ocean biological pump using only passive flux measurements. |
| first_indexed | 2024-12-22T05:00:14Z |
| format | Article |
| id | doaj.art-9ad666d34b03481bb76a733773c99538 |
| institution | Directory Open Access Journal |
| issn | 2296-7745 |
| language | English |
| last_indexed | 2024-12-22T05:00:14Z |
| publishDate | 2019-09-01 |
| publisher | Frontiers Media S.A. |
| record_format | Article |
| series | Frontiers in Marine Science |
| spelling | doaj.art-9ad666d34b03481bb76a733773c995382022-12-21T18:38:17ZengFrontiers Media S.A.Frontiers in Marine Science2296-77452019-09-01610.3389/fmars.2019.00535462510Zooplankton and Micronekton Active Flux Across the Tropical and Subtropical Atlantic OceanSantiago Hernández-León0María Pilar Olivar1María Luz Fernández de Puelles2Antonio Bode3Arturo Castellón4Cristina López-Pérez5Víctor M. Tuset6José Ignacio González-Gordillo7Instituto de Oceanografía y Cambio Global, IOCAG, Universidad de Las Palmas de Gran Canaria, Unidad Asociada ULPGC-CSIC, Canary Islands, SpainCSIC, Institut de Ciències del Mar, Barcelona, SpainCentro de Baleares, Instituto Español de Oceanografia, Palma, SpainCentro Oceanográfico de A Coruña, Instituto Español de Oceanografia, A Coruña, SpainCSIC, Unidad de Tecnología Marina, Barcelona, SpainCSIC, Institut de Ciències del Mar, Barcelona, SpainCSIC, Institut de Ciències del Mar, Barcelona, SpainInstituto Universitario de Investigación Marina, Universidad de Cádiz, Cádiz, SpainQuantification of the actual amount of carbon export to the mesopelagic layer by both zooplankton and micronekton is at present a gap in the knowledge of the biological pump. These organisms perform diel vertical migrations exporting carbon through respiration, excretion, mortality, and egestion during their residence at depth. The role of zooplankton in active flux is nowadays partially assessed. However, micronekton active flux is scarcely known and only a few studies addressed this downward transport. Even less is known about the capacity of both communities to export carbon in the ocean. Here, we show the results of zooplankton and micronekton active flux across a productivity gradient in the tropical and subtropical Atlantic Ocean. Biomass vertical distribution from the surface up to 800 m depth by day and night was studied during April 2015 in a transect from 9°S to 25°N, covering from the quite oligotrophic zone off Brazil to the meso- and eutrophic areas of the equator, Guinea Dome, and the oceanic upwelling off Northwest Africa. Zooplankton and micronekton migrant biomass was estimated from day and night catches at different layers of the water column using MOCNESS-1 (1 m2 mouth area) and Mesopelagos (35 m2) nets, respectively. Respiratory flux was assessed by measuring the enzymatic activity of the electron transfer system (ETS) of organisms at depth. Results showed a close relationship between migrant biomass and respiratory flux in zooplankton and micronekton as expected. Using a rather conservative 50% of efficiency for the net used to capture micronekton, respiratory flux resulted in similar values for both communities. Gravitational (passive) flux measured using sediment traps increased from the oligotrophic toward the meso- and eutrophic zones. Total active flux (including respiration and estimated mortality, excretion, and gut flux) by zooplankton and micronekton accounted for about 25% of total flux (passive plus active) in oligotrophic zones. Total active flux also increased toward meso- and eutrophic zones, reaching about 80% of total flux and being at least twofold higher than passive flux. These results alert about an important underestimation of the ocean biological pump using only passive flux measurements.https://www.frontiersin.org/article/10.3389/fmars.2019.00535/fullbiological pumppassive fluxactive fluxzooplanktonmicronektonAtlantic Ocean |
| spellingShingle | Santiago Hernández-León María Pilar Olivar María Luz Fernández de Puelles Antonio Bode Arturo Castellón Cristina López-Pérez Víctor M. Tuset José Ignacio González-Gordillo Zooplankton and Micronekton Active Flux Across the Tropical and Subtropical Atlantic Ocean Frontiers in Marine Science biological pump passive flux active flux zooplankton micronekton Atlantic Ocean |
| title | Zooplankton and Micronekton Active Flux Across the Tropical and Subtropical Atlantic Ocean |
| title_full | Zooplankton and Micronekton Active Flux Across the Tropical and Subtropical Atlantic Ocean |
| title_fullStr | Zooplankton and Micronekton Active Flux Across the Tropical and Subtropical Atlantic Ocean |
| title_full_unstemmed | Zooplankton and Micronekton Active Flux Across the Tropical and Subtropical Atlantic Ocean |
| title_short | Zooplankton and Micronekton Active Flux Across the Tropical and Subtropical Atlantic Ocean |
| title_sort | zooplankton and micronekton active flux across the tropical and subtropical atlantic ocean |
| topic | biological pump passive flux active flux zooplankton micronekton Atlantic Ocean |
| url | https://www.frontiersin.org/article/10.3389/fmars.2019.00535/full |
| work_keys_str_mv | AT santiagohernandezleon zooplanktonandmicronektonactivefluxacrossthetropicalandsubtropicalatlanticocean AT mariapilarolivar zooplanktonandmicronektonactivefluxacrossthetropicalandsubtropicalatlanticocean AT marialuzfernandezdepuelles zooplanktonandmicronektonactivefluxacrossthetropicalandsubtropicalatlanticocean AT antoniobode zooplanktonandmicronektonactivefluxacrossthetropicalandsubtropicalatlanticocean AT arturocastellon zooplanktonandmicronektonactivefluxacrossthetropicalandsubtropicalatlanticocean AT cristinalopezperez zooplanktonandmicronektonactivefluxacrossthetropicalandsubtropicalatlanticocean AT victormtuset zooplanktonandmicronektonactivefluxacrossthetropicalandsubtropicalatlanticocean AT joseignaciogonzalezgordillo zooplanktonandmicronektonactivefluxacrossthetropicalandsubtropicalatlanticocean |