Nutrient and phytoplankton dynamics on the inner shelf of the eastern Bering Sea

Abstract

In the Bering Sea, the nitrogen cycle near Nunivak Island is complicated due to limited nutrient replenishment across this broad shelf, and substantial nitrogen loss through sedimentary processes. While diffusion at the inner front may periodically support new production, the inner shelf in this region is generally described as a regenerative system. This study combines hydrographic surveys with measurements of nitrogen assimilation and benthic fluxes to examine nitrogen cycling on the inner shelf, and connectivity between the middle and inner shelves of the southern and central Bering Sea. Results establish the inner shelf as primarily a regenerative system even in spring, although new production can occur at the inner front. Results also identify key processes that influence nutrient supply to the inner shelf and reveal coupling between the middle shelf nutrient pool and production on the inner shelf.