2003/10/24 by Davide Valenti, D. Valenti, Valenti, D. +5
Computer Science · Environmental Science · Physics and Astronomy · #Ecosystem dynamics and resilience #FOS: Physical sciences #Nonlinear Dynamics and Pattern Formation #Statistical Mechanics (cond-mat.stat-mech) #cond-mat.stat-mech #stochastic dynamics and bifurcation
paper · pdf · doi:10.48550/arxiv.cond-mat/0310587
7 pages, 7 figures, 22 panels. To appear in Modern Problems in Statistical Physics
arxiv created 2003/10/24 · openalex publication_date 2003/10/24 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28
We study the role of multiplicative colored noise for different values of the correlation time τc in the dynamics of two competing species, described by generalized Lotka-Volterra equations. The multiplicative colored noise 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. The bistable potential is useful to describe the coexistence and exclusion dynamical regimes of the ecosystem. Noise-induced periodic oscillations of the species concentrations and stochastic resonance phenomenon appear due to the presence of the multiplicative noise. We find that for low values of the correlation time τc the response of the system coincides with that obtained with multiplicative white noise. For higher values of τc the coherent response of the system and the maximum of the signal-to-noise ratio, signature of the stochastic resonance phenomenon, are shifted towards higher values of the noise intensity.