Nitrification in the Lower Euphotic Zone at Station ALOHA: Patterns and Significance

John Dore

Abstract

The depth distributions of nitrification rates are considered with respect to overall nitrogen cycling in the lower euphotic zone. Nitrification is shown to be insignificant within the "classical" primary nitrite maximum (PNM), but may be the source of the newly-described nitrite "bump" below the larger peak of the PNM. New data from HOT-50 lends additional support to this hypothesis. The possible consequences of the observed nitrification patterns on new and recycled production estimates are considered.