Average conditions for permanence and extinction in nonautonomous Gilpin-Ayala competition model

摘要

In this paper, we consider a general nonautonornous n-species Gilpin-Ayala competitive system. which is more general and more realistic than classical Lotka-Volterra competition model. By means of Ahmad and Lazer's definitions of lower and upper averages of a function. we first Live the average conditions for the permanence and global attractivity of the system. Next. for each r <= n the average conditions on the coefficients are provided to guarantee that r of the species in the system are permanent while the remaining n - r species are driven to extinction. Examples show the feasibility of the main results. (c) 2005 Elsevier Ltd. All rights reserved.