Figure 2. Isolines of the dispersal kernel-based analogue I˜ of the immigration parameter (Eq. 1) computed as a function of the community radius R_c (1<R_c<600 m) and of the 95% quantile (1<<600 m) of the Gaussian (left) and Cauchy (right) dispersal kernels.

The dispersal dependent (DD) regime encompasses situations when I˜ is mostly sensitive to (vertical portion of the isolines), while the size dependent (SD) regime sets in when I˜ is mostly sensitive to R_c (horizontal portion of the isolines).