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arXiv · 2008.02907

Critical patch size reduction by heterogeneous diffusion

M. A. F. dos Santos·V. Dornelas·E. H. Colombo·C. Anteneodo
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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.

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M. A. F. dos Santos, V. Dornelas, E. H. Colombo, C. Anteneodo. 2020-08-07. Critical patch size reduction by heterogeneous diffusion. https://doi.org/10.1103/physreve.102.042139

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