Diel cycles of inorganic nitrogen uptake in a natural phytoplankton population dominated by <i>Gonyaulax polyedra</i>1

Abstract

The diel characteristics of nitrate and ammonium uptake in a Gonyaulax polyedra bloom were observed during a field program along the west coast of Baja California. The simultaneous presence of light and inorganic nitrogen (especially nitrate) appeared necessary to generate uptake rates sufficiently high to allow growth of these dinoflagellate populations to bloom proportions. Field data from this and other areas revealed no significant differences in the light requirements of diatoms and dinoflagellates.