Fig. 4
From: Global diversity and biogeography of DNA viral communities in activated sludge systems
Taxonomy and clustering of activated sludge (AS) viruses with known viruses. A The number of shared viral clusters (VCs) in AS with different wastewater types and NCBI viral RefSeq. B The number of shared VCs in AS from different countries. C The relative abundance of viral taxa (n = 22,673) across different AS samples based on the normalized mean coverage. AS samples are separated by wastewater types (black lines) and countries (different colors). Viral taxa with relative abundance of less than 0.1% are classified as others