Table 1.

Bacterial genera with differential abundance in ground and surface water sources.

Genus	Groundwater		Surface water		p-value
	Mean	St. error	Mean	St. error
Acidovorax	0.018	0.005	0.001	0.001	0.039
Burkholderia	0.744	0.046	0.001	0.000	0.001
Clostridium	0.001	0.001	0.014	0.003	0.024
GpIIa	0.000	0.000	0.011	0.002	0.017
Ilumatobacter	0.000	0.000	0.011	0.003	0.025
Methylocystis	0.009	0.002	0.082	0.007	0.007
Mycobacterium	0.001	0.000	0.032	0.008	0.035
Polynucleobacter	0.000	0.000	0.016	0.001	0.008
Ralstonia	0.016	0.003	0.000	0.000	0.021
Spartobacteria_genera_incertae_sedis	0.000	0.000	0.078	0.009	0.010
Unclassified	0.110	0.021	0.684	0.019	0.000

Average relative abundance of sequences assigned to that genus (Mean), standard error of the corresponding average (St. error) and p-value describing the significance of the differential abundance observed between the two populations, for genera representing at least 1.0% of the sequences in either of the water sources. The computed FDR of these genera is 0.05, thus we expect that less than 1 of the 11 represent false positives.