Hidden biosphere in an oxygen-deficient Atlantic open-ocean eddy: future implications of ocean deoxygenation on primary production in the eastern tropical North Atlantic

摘要

The eastern tropical North Atlantic (ETNA) is characterized by a highly productive coastal upwelling system and a moderate oxygen minimum zone with lowest open-ocean oxygen (O-2) concentrations of approximately 40 mu mol kg(-1). The recent discovery of re-occurring mesoscale eddies with close to anoxic O-2 concentrations (< 1 mu mol kg(-1)) located just below the mixed layer has challenged our understanding of O-2 distribution and biogeochemical processes in this area.