Critical patch size reduction by heterogeneous diffusion

TL;DR

This paper investigates how heterogeneous diffusion in a bounded environment can reduce the critical patch size needed for species survival, highlighting the importance of landscape heterogeneity in ecological persistence.

Contribution

It demonstrates that spatially variable diffusion coefficients generally lower the minimal habitat size required for population survival compared to uniform diffusion.

Findings

Heterogeneous diffusion reduces critical patch size.

Survival is more likely in heterogeneous environments.

Critical size is smaller than in homogeneous cases.

Abstract

Population survival depends on a large set of factors that includes environment structure. Due to landscape heterogeneity, species can occupy particular regions that provide the ideal scenario for development, working as a refuge from harmful environmental conditions. Survival occurs if population growth overcomes the losses caused by adventurous individuals that cross the patch edge. In this work, we consider a single species dynamics in a bounded domain with a space-dependent diffusion coefficient. We investigate the impact of heterogeneous diffusion on the minimal patch size that allows population survival and show that, typically, this critical size is smaller than the one for a homogeneous medium with the same average diffusivity.