Extinction in two dimensional nonautonomous Lotka–Volterra systems with the effect of toxic substances

In this paper, we consider a nonautonomous competitive Lotka–Volterra system of two species with the effect of toxic substances. It is shown that toxic substances play an important role in the extinction of species. We prove that one of components will be driven to extinction while the other will stabilize at a certain solution of a logistic equation under some conditions.