Interactions between dispersal, competition, and landscape heterogeneity

摘要: It is widely acknowledged that space has an important role in population regulation, yet more specific knowledge into how the relevant factors interact attains little consensus. We address this issue via a stochastic, individual based model of dynamics, continuous time framework. represent habitat quality as continuously varying surface over two-dimensional landscape, and assume affects either fecundity (rate propagule production) or probability establishment. control properties landscape by two parameters, which we call patch size (the characteristic length scale variation), level heterogeneity difference between poor high areas). In addition to such exogenous variability, also account for endogenous causing spatial variation assuming localised dispersal competition. find general positive effect on density, hence it beneficial improve best at expense worst habitat. With regards size, intermediate optimum, due conflict minimising loss propagules low regions maximising benefits heterogeneity. consequences regional stochasticity allowing environmental conditions change time. The cost having track where favourable have moved ultimately reduces size.