Fig. 3
From: Global diversity and biogeography of DNA viral communities in activated sludge systems
Alpha and beta diversity analysis of AS viral communities. A Shannon index of viral communities across different datasets. The significant difference test is determined using Student’s t-test, ns indicates no significant difference, *** indicates P < 0.001, **** indicates P < 0.0001. The significant differences in viral diversity in AS with different countries are shown in the heatmap. B NMDS analysis of viral communities based on the Bray–Curtis dissimilarity calculated by the normalized mean coverage of viral operational taxonomic units (vOTUs). ANOSIM is applied to detect the differences in viral communities in AS between different wastewater types or countries