Scaling up marine nitrogen fixation: from growth processes to global models

The discovery of new diazotrophic organisms in the world's ocean has widened the puzzle of the oceanic, nitrogen budget. Although cultured, diazotrophic strains like Trichodesmium, Crocosphaera and Cyanothece are only a few amongst the wide diversity of nitrogen fixers, culture approaches have pinpointed number of physiological properties that progressively bring a better understanding of the distribution and growth efficiencies of these organisms in the world’s ocean. Now, this information has to be extrapolated to larger scales and translated into biogeochemical models to prove helpful to the field of biogeochemistry. We are developing models of nitrogen fixation at different scales in order to analyze and discuss what level of information matters that should be incorporated in biogeochemical models.