Diel Vertical Migration (DVM) of zooplankton and micronekton is a characteristic behavioral pattern in which their vertical distribution varies over the day as a response to predation avoidance. These organisms transport carbon from the surface to the deep layers, thus enhancing the efficiency of the biological carbon pump and sustaining the metabolic requirements of mesopelagic communities. Zooplankton active flux has been addressed in different studies, supporting fluxes equivalent up to 10-30% of particle export. However, the role of micronekton in the active flux is scarcely known, and the capacity of both communities to export carbon is still poorly studied. Here, we show the results of both active (zooplankton and micronekton) and passive fluxes from the Mediterranean Sea to the Atlantic Ocean around the Iberian Peninsula. Passive flux showed that particulate organic carbon (POC) was rather low even in the most productive zones of the Atlantic side. Regarding the active flux, we obtained a close relationship between migrant biomass and respiratory flux for both communities. Zooplankton total flux decreased in the northern Atlantic stations while micronekton flux increased, reaching more than two-times POC values. These results evidence the need to increase active flux estimations by both zooplankton and micronekton communities to better assess the role of the pelagic fauna in the biological carbon pump.

Primary Presenter: Maria Couret, Instituto de Oceanografía y Cambio Global (mariacouhuertas@gmail.com)

Authors:

Maria Pilar Olivar, Institut de Ciències del Mar  ()

Jose María Landeria, Instituto de Oceanografía y Cambio Global y Universidad de Las Palmas de Gran Canaria  ()

Airam Sarmiento Lezcano, Instituto de Oceanografía y Cambio Global y Universidad de Las Palmas de Gran Canaria  ()

Arturo Castellón, CSIC, Unidad de Tecnología Marina  ()

Javier Díaz-Perez, Instituto de Oceanografía y Cambio Global y Universidad de Las Palmas de Gran Canaria  ()

Santiago Hernández- León, Instituto de Oceanografía y Cambio Global y Universidad de Las Palmas de Gran Canaria  ()