How spatial structure of species and disturbance influence the ecological invasion

Ecological invasion is a common phenomenon and a critical driver of species’ coexistence in nature. We establish a pair approximation model to explore the possible invasive results of an exploitative competition food web formed by ecological invasion. Global and local hunting strategies of predators are considered. The influence of initial densities and the initial spatial structure of both native and invasive species for invasive results are analyzed. Generally, better local predation capacity and higher initial density of the invasive species favor successful invasion. Interestingly, the initial spatial structures of both native and invasive species can alter the invasive results. Whether higher aggregation of invasive species promotes invasion depends on the species’ predation strategies. Then two kinds of disturbance defined as destructive disturbance and targeted introductory disturbance are introduced. Three characteristics of disturbances are considered: the extent, spatial connectivity and periodicity. All the three characteristic have profound influence on the invasive results especially for the targeted introductory disturbance. Furthermore, the former kind of disturbance cannot eliminate the invasive species thoroughly while the latter not only can eliminate the invasive species but also can promote the coexistence of the native and invasive species depending on its three characteristics. Finally, several invasive events and hypotheses being reported are explained by our model. This study provides new insights into biodiversity conservation and invasion, and the results about disturbance can give us some inspirations on the control of invasion.