Abstract:
The efficiency of the biological carbon pump in the Southern Ocean (SO. is constrained by the availability of light and the micronutrient iron (Fe., which plays a critical role in the functioning of photosynthesis. The low Fe concentrations (<0.1 nM. in the SO surface waters, limits phytoplankton biomass, primary production, and influences the community composition. A greater understanding of the Fe biogeochemical cycle and its effects on SO phytoplankton species is required to make more accurate assessments and predictions on the impact of future climate change. Climate change is predicted to alter the physical (i.e., temperature, light, salinity. and chemical (i.e., nutrient concentrations, pH. environment of the SO, which in turn is expected to modify the physiological and metabolic functions of phytoplankton. Our current understanding of the interacting effects of these parameters on SO phytoplankton species is poorly understood. Furthermore, the potential evolutionary adaptation of phytoplankton to future predicted changes in these parameters is unknown. The goal of this study will allow us to better understand the SO, by contributing to our current knowledge of the Fe biogeochemical cycling and its effect on SO phytoplankton biomass, primary production and community composition through in situ SO experiments. Moreover, laboratory based culture experiments will assist in the understanding of whether climate change will have a positive, negative or zero-sum effect on the phytoplankton, and hence the biological uptake of CO2 by the oceans. The relationships between phytoplankton and the drivers of their primary production (light, temp, nutrients, etc.. will inform and constrain on existing biogeochemical parameters within Earth Systems models. - Abstract as displayed in the - Abstract booklet. The presentation on the day may differ from the - Abstract.
