Fig. 4
From: The microbial dark matter and “wanted list” in worldwide wastewater treatment plants
The network and “wanted list” of worldwide activated sludge. a The Zi (within-module connectivity) and Pi (among-module connectivity) scores of the worldwide activated sludge network. The nodes were classified into four categories, including module hubs (Zi > 2.5 and Pi < 0.62), connectors (Zi < 2.5 and Pi > 0.62), network hubs (Zi > 2.5 and Pi > 0.62), and peripherals (Zi < 2.5 and Pi < 0.62). b Overview of worldwide activated sludge network after removing low prevalence OTUs (show in < 30% samples) and independent nodes. c The “wanted list” of worldwide activated sludge. The 71 OTUs cover 39.7% averagely of total relative abundance in global activated sludge microbiota. The figure showed the highest abundance of those OTUs in EMP and activated sludge samples with 100% alignment and 100% identity