Jingxuan Li (IsoSiM student) UBC Earth and Ocean Sciences
Phytoplankton (marine microalgae) accounts for 50% of all photosynthetic activity on Earth. Iron, as an essential nutrient, is limiting phytoplankton growth and production in 30% of the surface ocean. Addition of 55Fe isotope to incubation seawater samples and subsequent measurement of cell radioactivity enable determination of Fe uptake rates by phytoplankton. Due to global warming, the Arctic Ocean is experiencing rapid change, such as enhanced sea-ice melting and light intensity. In addition, high seawater CO2 is causing the pH to decrease, especially in the Arctic Ocean. The present study examines Arctic phytoplankton’s response to climate change, including their capability and strategy to take Fe under future conditions of higher light and CO2 levels.