Table 1.

Key topological indices of microbial networks of ammonia-oxidizing archaea (AOA), nirS-, and nosZ-carrying denitrifiers.

Microbial Community		Topological Features
	Treatment	Nodes a	Edges b	Clustering Coefficient c	Network Diameter d	Shortest Paths e	Avg. Number of Neighbors f	Graph Density g
AOA	CK	35	38	0.424	2	88	2.171	0.064
	AR	15	11	0.400	2	24	1.467	0.105
nirS	CK	108	263	0.723	10	5850	4.870	0.046
	AR	43	72	0.756	2	164	3.349	0.080
nosZ	CK	143	362	0.773	7	8756	5.063	0.036
	AR	149	665	0.701	9	16248	8.926	0.060

^a Operational taxonomical units (OTUs) colored based on genus-level taxonomy; ^b Number of connections/correlations among nodes; ^c Denoting the highly interconnected structure of a particular region of a network; ^d The largest distance between two nodes; ^e Indicating how quickly the information can be transferred between two nodes; ^f Indicating the average connectivity of a node; ^g The ratio of the number of edges to the number of possible maximum edges. AOA: ammonia-oxidizing archaea; nirS and nosZ: nirS- and nosZ-carrying denitrifiers.