Table 1 Explanation and summary of simulation parameters.

s_f

1

[0, 1]

s_m = 0.35

Host affinity of mutualists (f = m) and pathogens (f = p).

s_p = 0.03

γ_f

2a

[0.1, 0.5]

γ_m = 0.21

Fecundity of microbes, represented as a proportion of microbes in any given cell that are dispersed as propagules.

γ_p = 0.15

b_f

2b

[2, 3]

b_t = 2.40

Exponent of power-law distribution. This indicates the dispersal limitation of both microbial guilds (f = m, f = p), or plants (f = t).

b_m = 2.82

b_p = 2.50

g

4

[5, 15]

8.80

The impact of microbes on host survival.

h

[0.2, 1.5]

0.40

Relative contribution of the mutualist community to seedling recruitment probability.

ζ

[0.8]

0.8

Relative fitness of the least fit plant species. The fitness values of plant species (i.e. ζ_j where j is the plant species), are evenly distributed between ζ and 1.

c_f

5

[0.5, 2]

c_m = 0.78

Exponent that scales the competitive ability of a microbe according to its effect on host survival.

c_p = 1.47

q_f

[−0.5, 2]

q_m = 0.91

Exponent that scales intrinsic growth rate of microbes with host affinity.

q_p = 1.64

r_f

[0.1, 2]

r_m = 1.31

Intrinsic growth rate of mutualists and pathogens.

r_p = 1.64

α_f

[0.5, 1.5]

α_m = 1.30

Competition coefficients of mutualists and pathogens.

α_p = 1.00