FIGURE 2.

Turnover rates of (A–F) O₂, NO₃^-, NO₂^-, NH₄⁺, N₂O, and N₂ and (G) mass balance of NO₃^- consumption in sinking Skeletonema aggregates at different ambient air-saturation levels. (A–F) Positive and negative rates correspond to production and consumption, respectively. (G) Color code of stacked bars refers to colors used in (B–F); white indicates NO₃^- consumption due to intracellular storage and/or assimilation. Means (+SD) of 5–9 individually incubated aggregates are shown. n.a., not applicable.