A trait-based approach is used to model how phytoplankton community structure might vary when nutrients are supplied periodically at multiple timescales.
Trait variation across phytoplankton ‘species’ is defined by an empirically supported three-way tradeoff between maximum growth rate, specific uptake affinity for phosphate, and internal storage capacity for phosphorus (Edwards et al. 2013).
400 species varying along on this tradeoff plane are initialized in the community, and competition proceeds, with species at very low abundance removed, until the dynamics converge on a periodic attractor.
The frequency and magnitude of nutrient pulses are varied to investigate how community trait structure and diversity respond. Nutrient pulses are reprented as mixing events with water below the surface mixed layer, which simultaneously dilute the phytoplankton populations. Variations in parameter values and the resulting changes in community structure are described in Smith and Edwards (2019).