From elemental process studies to ecosystem models in the ocean biological pump
The biological pump controls the transport of particles from the ocean surface to the deep sea. Vertical fluxes govern chemical gradients, playing a fundamental role in the carbon dioxide (CO2) ocean-atmosphere feedback, driving physicochemical properties of seawater, and providing resources for benthic ecosystems. Particles vary in size and composition, originating in every trophic level as detritus, fecal material, biogenic carbonates or the organisms biomass. A recent concern is that the concomitant increase in anthropogenic CO2 and temperature, may alter carbon fluxes and atmospheric feedbacks, as well as ecosystem shifts driven by organisms’ physiological and biogeochemical responses. This dissertation focused on poorly characterised biological pump compartments and processes that are central to assess potential implications of future climate scenarios.