Table 2. Diversity statistics and recovery of bacterial phyla from MFC anode biofilms and primary clarifier effluents.

Source	Anode biofilm				Primary clarifier effluent
Library ID	W1	W2	W3	W4	PC1	PC2	PC4
Sampling day	44	133	263	295	14	152	304
Shannon's Index	3.5	3.4	3.5	3.6	3.3	2.8	2.0
Simpson Diversity Index (1 - D)	0.96	0.94	0.96	0.97	0.94	0.80	0.66
Number of clones sequenced	88	84	77	73	72	146	91
Number of O.T.U. (99% cutoff)	47	43	41	46	40	54	27
Chao1 Richness	228±65	203±59	77±15	119±27	96±22	180±42	45±10
Sørensen's similarity coefficients
W1		0.18	0.11	0.11	0.09	0.06	0.11
W2			0.21	0.14	0.12	0.10	0.14
W3				0.32	0.03	0.00	0.00
W4					0.00	0.02	0.03
PC1						0.28	0.21
PC2							0.20