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. 2024 Apr 3;19(4):e0300875. doi: 10.1371/journal.pone.0300875

Table 1. Hypothesis testing framework and consensus approach (see methods) to verify differences in α and β microbial diversity (detailed results in S2 Table).

Location effects α diversity–ANOVA (ASVs frequencies) β diversity–PERMANOVA (CLR-CoDa) β diversity–PERMANOVA (ASVs frequencies)
ACE PD H IS CLR ASVs CLR aggregated
genera
untransformed 4rt root – log(X+1) presence/absence
Management Practice: Ma * **                
Altitude: Al                    
Crop: Cr                   *
Ma x Al * **     * * * * * *
Al x Cr                    
Ma x Cr                    
Site: Si (Ma x Al)         *** *** *** *** *** ***
Al x Ma x Cr                    
Cr x Si (Ma x Al) ** ***     *** *** *** *** *** ***
posthoc test Ma x Al            
high altitude conv. > agroec. Conv. > agroec.     Conv. ≠ agroec. Conv. ≠ agroec.
Low altitude conv. = agroec. Conv. = agroec.     Conv. = agroec. Conv. = agroec.
Dispersion effects (Anna Karenina)         β diversity–PERMDISP (CLR-CoDa)
        CLR ASVs CLR aggregated genera
Management Practice, High conv. > agroec. Conv. > agroec.
Management Practice, Low         conv. = agroec. Conv. = agroec.

ANOVAs (on ASVs frequencies) and PERMANOVAs (on either ASVs frequencies or centered log-ratio transformed, compositional data, CLR-CoDa) were used to test univariate and multivariate location effects of management practice (Ma: conventional vs agroecological), altitude (Al: high altitude vs low altitude), crop (Cr: watermelon vs cucumber), and site (list and coordinates in S1 File). PERMDISP, based on CLR-CoDa, was used to test dispersion effects on β diversity (Anna Karenina principle) promoted by different management practices either at high or low altitudes. FDR: p value corrected via False Discovery Rate. Tests on α microbial diversity considered Abundance Coverage Estimator (ACE), Faith’s Phylogenetic Diversity (PD), Shannon-Weiner (H) and the Inverse Simpson indexes (IS). The results of the post hoc tests implemented for Ma x Al are indicated.

*: P = <0.05

**: P = <0.001

***: P = <0.0001.