Marine diatoms are major contributors to global primary productivity and one of the most abundant photosynthetic organisms on our planet, but much remains to be learnt about the mechanisms through which they acquire carbon from seawater. In particular, the role of the diffusive boundary layer around large cells may present a substantial barrier to CO2 supply. We have developed methodologies to measure pH and carbonate chemistry at the surface of individual diatom cells to determine how carbonate chemistry in the diffusive boundary layer (DBL) influences carbon uptake. The research will inform us how cell size can influence nutrient acquisition strategies and will allow us to better predict how and why diatom communities may respond to changes in carbonate chemistry in current and in future oceans.

Natural Environment Research Council