Competition in a patchy world: insight from a new modeling approach

In the ocean, physical dynamics act to create variability in the availability of resources generating environmental ‘niches’ at every scale from micrometers to kilometers. Given the nonlinearity of most biological dynamics, it is important to understand how fine-scale bio-physical interactions may propagate to large scale ecosystem dynamics and carbon cycling. Here I present an approach for generalizing the impact of submesoscale bio-physical interactions on ecosystem dynamics using a statistical description of the perturbations induced by submesoscale processes. I use this model to investigate the impact of fine-scale heterogeneity in resource environment on ecosystem dynamics and carbon cycling. Specifically, the model provides insight into the combined impact of Jensen’s’ Inequality and competition in determining ecosystem structures. The model was applied to the Hawaiian Ocean Time-series site to explore the importance of fine-scale spatial and temporal heterogeneity on ecosystem composition and carbon dynamics at the site. Results suggest that community composition and export are impacted by the frequency of submesoscale front formation and that community dynamics in a heterogeneous resource environment differ significantly from a homogenous field.