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The survival analysis for a population in a polluted environment. (English) Zbl 1160.92041
Summary: This paper concentrates on studying the long-term behavior of a single species in a polluted closed environment. We improve the rudimentary population model of Hallam [see T. G. Hallam et al., J. Math. Biol. 24, 327–339 (1986; Zbl 0606.92022); Ecol. Modelling 8, 291–304 (1983)] and the classical G. C. Gallopin [Oecologia 7, 382–413, 414–432 (1971)] resource-consumer model, assuming that a born organism takes with it a quantity of internal toxicant, and the amount of toxicant stored in each living organism which dies is drifted into the environment. Sufficient criteria for persistence or extinction of the consumer population are obtained. The threshold between persistence and extinction will be established in some cases.
34C60Qualitative investigation and simulation of models (ODE)
37N25Dynamical systems in biology