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Stochastic resonance and noise delayed extinction in a model of two competing species

D. Valenti·A. Fiasconaro·B. Spagnolo
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Abstract

We study the role of the noise in the dynamics of two competing species. We consider generalized Lotka-Volterra equations in the presence of a multiplicative noise, which models the interaction between the species and the environment. The interaction parameter between the species is a random process which obeys a stochastic differential equation with a generalized bistable potential in the presence of a periodic driving term, which accounts for the environment temperature variation. We find noise-induced periodic oscillations of the species concentrations and stochastic resonance phenomenon. We find also a nonmonotonic behavior of the mean extinction time of one of the two competing species as a function of the additive noise intensity.

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D. Valenti, A. Fiasconaro, B. Spagnolo. 2003-10-27. Stochastic resonance and noise delayed extinction in a model of two competing species. https://doi.org/10.1016/j.physa.2003.09.036

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