Bridging the scale gap has appeared.
On homogenization methods in ecology. With Christina Cobbold and Brian Yurk
- Often, ecologists are challenged with a mismatch of scales: how do we up-scale from local variation and available data to landscape-level models and predictions?
- We present a general recipe for coarse-graining from local to landscape-scale reaction-diffusion equations when spatial heterogeneity is small in extent compared to dispersal of organisms. Our homogenization approach uses the fundamental ecological concepts of Turchin’s residence index and Skellam’s dynamic level.
- Our approach opens avenues to new ecological theory that connects different scales, which we illustrate using predator-prey interactions. It also presents opportunities for using the increasingly available small-scale data for landscape-level predictions, such as range expansion rates.
- We find several unexpected nonlinear relationships between the movement behavior on the local level and the spatially implicit and explicit outcomes at the landscape-level, e.g., predator spread rate may increase or decrease when predators move faster locally. Our method provides a mechanistic link for population dynamics and data integration across spatial and temporal scales, addressing a fundamental goal of landscape ecology.