Fig. 4From: Archaeal and bacterial communities assembly and co-occurrence networks in subtropical mangrove sediments under Spartina alterniflora invasionCo-occurrence network of archaeal and bacterial OTUs based on node features of the network (a) and Zi-Pi plot (b). a: Degree (top left); betweenness (top right); eigenvector centrality (bottom left); and closeness (bottom right). ns: not significant; *** P < 0.001. b: Zi-Pi plot showing the distribution of archaeal and bacterial OTUs based on their topological roles. Each symbol represents an OTU. The topological role of each OTU was determined according to the scatter plot of within-module connectivity (Zi) and among-module connectivity (Pi). (i) network hubs: nodes with Zi > 2.5 and Pi > 0.62; (ii) module hubs: nodes with Zi > 2.5 and Pi ≤0.62; (iii) connectors: nodes with Zi ≤ 2.5 and Pi > 0.62; and (iv) peripheral nodes: nodes with Zi ≤ 2.5 and Pi ≤0.62Back to article page