Consumption of silicic acid below the euphotic zone by sedimenting diatom blooms in the Barents Sea

Abstract

Massive sedimentation of spring phytoplankton blooms occurs in the Barents Sea as in many other shelf sea environments. Associated with this sedimentation there is a large decrease in concentration of dissolved shcic acid below the nitracline. This decrease is apparently related to resting spore formation of the dominant &atom species Chaetoceros socids. The deep shcic acid consumption seems to be a regular and extensive phenomenon which results in a vertical separation of the shcic acid gradient from the nitracline. This d disfavour further growth of diatoms during the summer season due to reduced upward transport of silicic acid by vertical mixing.