Table A1.

β-Diversity between environment types.

	Aquaria + biofilters	Caves	Coastal sediments	Coral + sponges	Groundwater	Hot springs	Hydrothermal vents	Lakes + rivers	Marine sediments	Seas	Soils	Ocean water column	Wastewater treatment
Aquaria + biofilters		0	0.010	0	0	0	0	0	0	0	0	0	0
Caves	0		0	0	0	0	0	0	0	0	0	0	0
Coastal sediments	0.042	0		0.009	0.004	0.004	0	0.013	0.013	0.003	0.031	0.010	0.008
Coral + sponges	0.028	0	0.046		0	0	0	0	0	0.008	0	0.023	0
Groundwater	0	0	0.024	0		0	0	0.022	0	0	0.004	0	0.009
Hot springs	0	0.037	0.041	0	0.029		0	0.019	0.006	0	0.015	0	0.006
Hydrothermal vents	0	0	0.008	0.013	0	0		0	0.026	0	0	0.027	0
Lakes + rivers	0	0	0.087	0	0.089	0.134	0		0.003	0	0.035	0	0.016
Marine sediments	0.021	0.008	0.109	0.017	0.007	0.057	0.103	0.048		0	0.017	0.008	0.011
Seas	0	0	0.011	0.032	0	0	0.031	0	0.008		0	0.019	0
Soils	0	0	0.126	0	0.027	0.091	0	0.121	0.074	0		0	0.012
Ocean water column	0.025	0	0.050	0.071	0	0.007	0.113	0.007	0.038	0.075	0.003		0
Wastewater treatment	0.024	0	0.044	0	0.020	0.061	0	0.090	0.056	0	0.045	0

Values represent the Jaccard similarity index for (above the diagonal) amoA nucleotide OTUs at the 99% identity level and (below the diagonal) 95% identity level.