R0 as a function of the field size for exponential dispersal kernel

The file represents the basic reproductive number, R0, as a function of the field size for exponential dispersal kernel. 1st column distance [m]; 2nd column R0. Spatial grid 60x60 gridpoints. Plotted as solid curve in Fig. 1 (up to values of d of about 193 m). The data was generated by numerical solution of Eq. (6) in the manuscript