Fig. 3

Deterministic and stochastic processes in microbiome assembly. A and B Relative contribution of determinism and stochasticity on bacterial (A) and fungal (B) microbiota assembly based on the β-Nearest Taxon Index (βNTI) values. The βNTI values were calculated using null model, and |βNTI|≥ 2 and |βNTI|< 2 represent dominant determinism and stochasticity in driving microbiome assembly, respectively. The percentage above and below the violin plot represent the proportion of the deterministic processes and stochastic processes in microbiome assembly, respectively. C and D. The relative importance of five ecological processes in bacterial (C) and fungal (D) microbiota (heterogeneous selection: βNTI <  − 2, homogeneous selection: βNTI >  + 2, dispersal limitation: |βNTI|< 2 and RCBray > 0.95, homogenizing dispersal: |βNTI|< 2 and RCBray < − 0.95, and undominated: |βNTI|< 2 and |RCBray|< 0.95) along the soil–plant continuum based on the β-Nearest Taxon Index (βNTI) and Bray–Curtis-based Raup-Crick Index (RCBray)