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Noise Induced Phenomena in Lotka-Volterra Systems

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

We study the time evolution of two ecosystems in the presence of external noise and climatic periodical forcing by a generalized Lotka-Volterra (LV) model. In the first ecosystem, composed by two competing species, we find noise induced phenomena such as: (i) quasi deterministic oscillations, (ii) stochastic resonance, (iii) noise delayed extinction and (iv) spatial patterns. In the second ecosystem, composed by three interacting species (one predator and two preys), using a discrete model of the LV equations we find that the time evolution of the spatial patterns is strongly dependent on the initial conditions of the three species.

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B. Spagnolo, A. Fiasconaro, D. Valenti. 2003-10-27. Noise Induced Phenomena in Lotka-Volterra Systems. https://arxiv.org/abs/cond-mat/0310585

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