Permanence of delay competitive systems with weak Allee effects

摘要

This study discusses a multispecies delay competitive system with weak Allee effects. In the situation where the model is a single species, the weak Allee effect represents a biological mechanism in which an increase in population is beneficial for low densities, but detrimental for high densities. In other words, the per-capita growth rate of each species is formulated by a sign-changing function of population density. In this paper, an existence theorem of positive equilibrium is established using the Brouwer degree theory. For cases without intraspecific delays, it is shown that the system has the property of permanence. Furthermore, a sufficient condition for a positive equilibrium to be globally attractive is obtained by means of the Lyapunov method.