Permanence for General Nonautonomous Impulsive Population Systems of Functional Differential Equations and Its Applications

In this paper, we investigate general impulsive nonautonomous population dynamical systems of functional differential equations. By utilizing the method of multiple Liapunov-like functionals to construct the permanence region, a general criterion on the permanence for the system is established. Furthermore, as applications of this general criterion, a class of impulsive nonautonomous n-species Lotka-Volterra competitive systems with delays and a class of impulsive nonautonomous 3-species Lotka-Volterra food chain systems with delays are discussed. Some new and useful sufficient conditions on the permanence for these systems are established.