Fig. 2

Heatmap of the Pearson correlation coefficients calculated from the MAGs coverage values and histogram of the main species abundance. A Histogram of the relative abundance for the most abundant species in the biofilm observed in AD metagenomes available in the MiGa Biogas microbiome database. References for the corresponding works are reported on the left side, and the samples of the present work are marked in red. B Pearson correlation coefficient calculated considering the relative abundance profile of the MAGs present in the biofilm community in a global dataset based on the AD metagenomes available in MiGa Biogas microbiome database. The positive correlations are reported in green color, the negative correlations in red color and the correlations for which the p value was lower than the threshold (< 0.05) in grey color. The marked squares highlight the positive correlations between the most abundant species in the biofilm