TABLE 3.

Diversity of organisms in clone libraries for treated water at the plant and biofilms in the distribution systems of supply A and supply B

Source and type of organism	No. of clones	No. of OTUs identified	Coverage indexa	Total OTU richness (Chao1 estimation)b
				Mean	Lower limit	Upper limit
Eukaryotes in clone libraries
Supply A	272	108	39.7	159	136	204
Supply B	273	115	42.1	145	91	277
Total	545	219c	40.2	390	328	487
Free-living protozoa in clone libraries
Supply A	133	54c	40.6	113	81	187
TW-A	44	25	56.8	34	28	55
BF-Ad	89	30	33.7	158	70	444
Supply B	120	72c	60.0	163	112	274
TW-B	71	43	60.6	134	75	297
BF-Bd	49	31	63.3	45	32	88
Total	253	127c	50.2	281	212	407

^aNumber of OTUs/number of sequences × 100% (22).

^bThe Chao1 index (11) was calculated with DOTUR (59).

^cThe total number of OTUs excludes OTUs which were obtained from more than one sample type.

^dThe data are totals for the three analyzed biofilm samples.