Diel variations in some important phytoplankton parameters during a 24 hours sampling period in Balsfjorden, Tromsø and Skjomentfjorden, Nordland, North Norway
Every fourth hour in 24 h periods measurements were made of temperature, salinity, plant nutrients, incident radiation at three m depth, sub-surface light extinction, chlorophyll a, phaeophytin, particulate carbon and nitrogen, cell counts, zooplankton dry weight biomass, in situ primary production (14C), incubator carbon assimilation (14C), heterotrophic activity (14C glucose assimilation), and horizontal variation in chlorophyll a over one nautical mile. The marked variations in all parameters were probably generated by the combined effects of wind-driven circulation of water masses in the fjord and phytoplankton patches. This study stresses the presence of spatial and temporal changes in fjords, and that data conducted from one or few stations should be interpreted with care
