Fig. 1

The relationship between modified stochasticity ratio (MST) and (a) dilution level, (b) species richness, and (c) the Shannon index in the microcosm study. MST represents the relative importance of stochastic process in community assembly. MST smaller than 0.5 represents stronger deterministic processes than stochastic processes and MST larger than 0.5 represents stronger stochastic processes than deterministic processes. Dilution level equals to the logarithmically transformed dilution factor based on 10. Species richness is logarithmically transformed based on 10 before the calculation of Pearson’s correlation. The lines show the result of linear regression and the shaded areas represent 95% confidence intervals. Here, r represents the Pearson’s correlation and *** represents P < 0.001.