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arXiv · 2011.11808

Universality of noise-induced resilience restoration in spatially-extended ecological systems

Cheng Ma·Gyorgy Korniss·Boleslaw K. Szymanski·Jianxi Gao
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Abstract

Many systems may switch to an undesired state due to internal failures or external perturbations, of which critical transitions toward degraded ecosystem states are a prominent example. Resilience restoration focuses on the ability of spatially-extended systems and the required time to recover to their desired states under stochastic environmental conditions. While mean-field approaches may guide recovery strategies by indicating the conditions needed to destabilize undesired states, these approaches are not accurately capturing the transition process toward the desired state of spatially-extended systems in stochastic environments. The difficulty is rooted in the lack of mathematical tools to analyze systems with high dimensionality, nonlinearity, and stochastic effects. We bridge this gap by developing new mathematical tools that employ nucleation theory in spatially-embedded systems to advance resilience restoration. We examine our approach on systems following mutualistic dynamics and diffusion models, finding that systems may exhibit single-cluster or multi-cluster phases depending on their sizes and noise strengths, and also construct a new scaling law governing the restoration time for arbitrary system size and noise strength in two-dimensional systems. This approach is not limited to ecosystems and has applications in various dynamical systems, from biology to infrastructural systems.

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Cheng Ma, Gyorgy Korniss, Boleslaw K. Szymanski, Jianxi Gao. 2020-11-24. Universality of noise-induced resilience restoration in spatially-extended ecological systems. https://doi.org/10.1038/s42005-021-00758-2

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