quota model development

We are currently developing a “Quota” model which includes internal cellular processes such as photosynthesis, respiration and nutrient storage (the quota). This approach provides a more detailed representation of plankton physiology, and allows us to focus on some potentially important mechanisms in plankton ecology. The quota model was developed over 40 years ago, and has been extensively applied in laboratory studies of marine plankton. Switching to this approach is not only more realistic, but also allows us to take advantage of a wealth of empirical data. Initially, the model will be used to investigate the ecology of “mixotrophic” plankton, which combine autotrophic photosynthesis with the heterotrophic consumption of organic matter.

diatoms

Figure caption: Schematic of a mixotrophic plankton cell represented using the quota approach. Cellular carbon, nitrogen and chlorophyll are all dynamically included. Cells can gain energy and biomass by fixing inorganic carbon through photosynthesis or by consuming other cells. The internal stores of a number of different macro- and micro-nutrients can also be represented. Cells have the potential to accumulate reserves when resources are abundant, allowing them to survive for longer when they are not.

For more information contact Ben Ward