Variation in the transfer of energy in marine plankton along a productivity gradient in the Atlantic Ocean

Plankton play a key role in oceanic carbon flux as the primary biological mechanism for the sequestration of carbon out of the atmosphere into surface waters. The transfer of energy between phytoplankton and zooplankton can be inferred from regular patterns in population size structure, where plots of abundance within size classes typically show a power-law dependence on size. Here we analyze such picoplankton to mesozooplankton size spectra along a 50°N to 50°S transect in the Atlantic. Contrary to common perception, the transfer efficiency in the oceans is not related to ecosystem productivity. Our results challenge the view that biomass transfer efficiency is lower in oligotrophic oceanic ecosystems. This suggests that global carbon flux models should reconsider the trophic transfer efficiency of productive and oligotrophic areas.