Permanence and extinction for dispersal population systems

This paper studies the effect of dispersal on the permanence of population models in poor patchy environment. We first consider the logistic system with dispersal for single species and obtain the conditions for its permanence. On the basis of the conditions, we then consider a periodic predator– prey system where the prey can disperse among several patches. A necessary and sufficient condition is obtained for the permanence of the periodic predator–prey system. We discuss the biological implications of the main results.  2004 Elsevier Inc. All rights reserved