Results
We successfully fitted the negative exponential function to all the simulated results and plotted the three estimated parameters (δ, ε, and ζ) and intercepts (ζ – δ) along with the change in the parameter values of the neutral model (θ, J , d , and m ). The blue and orange circles indicate the results of the Bray–Curtis and Sørensen dissimilarity indices, respectively. First, as the fundamental biodiversity number (θ) increased, the parameters δ and ζ and the intercepts (ζ – δ) increased (Fig. 3a, i, m), but the parameter ε remained constant (Fig. 3e). Second, as the local community size (J ) increased, the parameters δ and ζ and the intercepts (ζ – δ) decreased (Fig. 3b, j, n); however, the parameter ε increased and then remained constant when J was larger than approximately 10,000 (Fig. 3f). Third, as mortality rate (d ) increased, the parameters δ and ζ and the intercepts (ζ – δ) decreased (Fig. 1c, k, o), but the parameter ε increased (Fig. 3g). Finally, as immigration rate (m ) increased, the parameters δ and ζ and the intercepts (ζ – δ) decreased (Fig. 3d, l, p), but the parameter ε increases (Fig. 3h).