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How do the spatial structure and time delay affect the persistence of a polluted species. (English) Zbl 1039.34073
The author analyzes toxicant-population models with discrete diffusion or time delay. It is shown that there exists a threshold for each system such that below the threshold the population is uniformly persistent, and above the threshold the population goes to extinction. It is shown that dispersal allows a large threshold, that is, dispersal can increase the endurance effectiveness of the population subject to a toxicant, and time delay has no effect on the threshold result.
MSC:
34K60Qualitative investigation and simulation of models
34K20Stability theory of functional-differential equations
34K25Asymptotic theory of functional-differential equations
92D25Population dynamics (general)