Table 2.

Numbers of sequences analyzed and operational taxonomic units and Shannon and Simpson diversity indices for the hsp65 gene sequences of NTM in the different drinking water samples^a

Treatment plant	Location	Season	No. of sequences	No. of OTUs	Diversity index
					Shannon	Simpson
SW1	DS 1	W	227	28	2.2	0.81
SW1	DS 2	W	114	16	1.6	0.64
SW1	DS 3	W	78	8	1.2	0.54
SW1	DS 1	S	96	26	2.4	0.85
SW1	DS 2	S	112	21	2.2	0.82
SW1	DS 3	S	91	11	1.5	0.70
SW2	DS 1	W	114	7	1.1	0.58
SW2	T	S	86	4	0.9	0.51
SW2	DS 1	S	167	14	1.8	0.78
SW2	DS 2	S	121	18	2.0	0.78
SW3	DS 1	S	139	21	2.3	0.84
SW3	DS 2	S	665	20	1.2	0.51
SW4	T	S	171	7	1.1	0.56
SW4	DS 1	S	161	23	1.9	0.72
GW1	T	S	329	8	0.2	0.072
GW1	DS 1	S	272	25	1.6	0.62

^aOTUs, operational taxonomic units; SW, surface water treatment plant; GW, groundwater treatment plant; DS, distribution system; T, treated water; W, winter; S, summer.