Fig. 2

Distance-decay relationship (DDR) for the three soil microbial communities. a DDR based on Sørensen dissimilarity along geographic distances for the bacterial, fungal, and protistan communities. Equation for the linear relationships is given in the plot with the corresponding P-values, which were corrected for nonindependence of pairwise comparisons using a permutation test. Solid lines are the mean fits, and shading represents the 95% confidence intervals. b DDR slope significance test of soil communities and the significance of ANOVA test. Each bar and error bar are the mean and standard deviation, respectively. Different letters indicate significant differences based on the false discovery rate P-value (P < 0.05). The values on the bars are the slope β of DDR, representing the spatial turnover rate of species