Fig. 4: Effects of particle size, O2, and initial polysaccharide and polypeptide concentrations on N2 fixation rates.
From: Quantifying nitrogen fixation by heterotrophic bacteria in sinking marine particles
The total amount of fixed \({{\rm{N}}}_{2}\) per particle as a function of particle radius and initial labile polysaccharide (a), initial labile polypeptide (b), and surrounding \({{\rm{O}}}_{2}\) concentration (c). The white dashed line separates regions of occurrence and non-occurrence of \({{\rm{N}}}_{2}\) fixation (\({{\rm{N}}}_{{\rm{fix}}} > {10}^{-3}\) μg N particle−1). The horizontal magenta dashed lines indicate the base value for other plots, e.g., in (a), magenta dashed line represents the level of polysaccharide concentration in b and c. The chosen concentration ranges corresponds to those in natural particles60,81.
