RNA Virome Composition Is Shaped by Sampling Ecotype

Despite the remarkable diversity of RNA viruses, little is known about how the physical and biotic properties of local environments impact virome compositions. Utilizing an expansive metatranscriptomic data set from 32 different physical and geographic environments, we identified 2,683 novel viruses from soil, sediment, and animal faecal samples, greatly increasing the phylogenetic diversity of the RNA virosphere. Sediments and animal faeces were particularly rich sources of viruses. Environmental factors had a greater impact on the abundance and diversity of virus families with plant, fungal, and bacterial hosts than those associated with animals, suggesting that the former have adapted to their specific ecotypes. These data reveal the diversity and richness of RNA viromes at the ecotype scale and suggest that viruses are an integral ecosystem component.