The importance of diatom biodiversity in the response of Southern Ocean ecosystems and biogeochemistry to climate change


Antarctic biodiversity is supported by Southern Ocean phytoplankton. This region regulates global climate, but is warming at extraordinary rates. The adaptive capacities of these organisms will thus determine the fate of the entire ecosystem and cascading impacts on the carbon cycle. Impacts of large-scale changes in climate, across different timescales, on key ecosystem functions and biogeochemical cycles are typically assessed using ocean biogeochemical models. But these models neglect important known aspects of biodiversity, especially for Antarctic regions. We know that Antarctic phytoplankton are regulated by the micronutrient iron, making changes in iron supply and demand crucial to the underlying patterns of phytoplankton biodiversity and their response to climate change. However, because phytoplankton are also able to display plasticity in their demands for iron, diversity in their adaptive approaches may also be an important determinant of their ecological success and sensitivity to change. We know Antarctic diatoms have altered a range of aspects of their physiology, relative to temperate groups, but we do not know whether this affects model projections of how climate change will impact Southern Ocean biodiversity, productivity and biogeochemical cycles.

This PhD project is part of a ‘Climate and Biodiversity’ project that spans laboratories in the UK and France across the genomics and modelling disciplines. This position in Liverpool will be focussed on using state-of-the-art global ocean biogeochemical models that include new Southern Ocean diatom groups that have the key unique traits that make Antarctic diatoms unique as regards to their temperate cousins. This will exploit existing data concerning their photosynthetic architecture and iron acquisition strategies and will develop further in response to new knowledge generate by project collaborators. 

The PhD candidate will work closely with our partner Prof Laurent Bopp and collaborator Prof Chris Bowler at the Ecole Normale Supérieure in Paris to assess how changes in climate over the past 10,000 years compare to those changes occurring over the past 50 years and next 100 years affect the contribution of diatom biodiversity to Southern Ocean ecology, ecosystems and biogeochemical cycling.

There will be funds to support the exchange of the PhD student between the laboratory in Liverpool and those of partners in Paris during the project and for participation in conferences to present project findings.

Please note: the deadline for this project may be subject to change.