Dynamics of a Reaction–Diffusion–Advection System From River Ecology With Inflow

Abstract

This paper is to study the population dynamics of a single species model and a two-species competition model from river ecology with inflow. One interesting feature in these models is that species can flow into the river through the upstream end due to advective movement while both diffusive and advective movements will cause population loss at the downstream end. We first determine necessary and sufficient conditions for persistence of a single species, in terms of the critical habitat size and the critical advection rate. For the competition model, we investigate the joint effects of advection rates, interspecific competition intensities, and boundary conditions on global dynamics of the system. It shows that the strategy of smaller advection is beneficial for species to survive. Our results partially extend the previous works.