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Dynamics of a nonautonomous Leslie-Gower type food chain model with delays. (English) Zbl 1213.37126
Summary: A nonautonomous Leslie-Gower type food chain model with time delays is investigated. It is proved the general nonautonomous system is permanent and globally asymptotically stable under some appropriate conditions. Furthermore, if the system is periodic one, some sufficient conditions are established, which guarantee the existence, uniqueness, and global asymptotic stability of a positive periodic solution of the system. The conditions for the permanence, global stability of system, and the existence, uniqueness of positive periodic solution depend on delays; so, time delays are profitless.
MSC:
37N25Dynamical systems in biology
92D25Population dynamics (general)