The Arctic Ocean is rapidly changing. In recent decades the amount of silicic acid entering the Arctic Ocean has been declining. Silicic acid is a key element for diatoms, which dominate the Arctic phytoplankton community. Due to this change in nutrients concentrations and relative availability, we expect a shift in the microalgal community from diatoms to other species that do not require silicic acid such as the haptophyte, Phaeocystis pouchetti. This change in biodiversity at the base of the food chain will have consequences for the grazer community. In 2024 we want to use a mesocosm approach to assess changes in phytoplankton community composition under reduced silicic acid concentrations and how these changes subsequently affect trophic transfer. This is supported by side experiments on zooplankton grazing behaviour.
