Table 5.

Effect of biochar on archaeal and bacterial richness and diversity in a RUSITEC system, with a mixed hay-silage-concentrate diet.

	Biochar (mg/d)				P-value
	Control, 0	400	800	SEM	Treat	L	Q
Liquid-associated microbes
Day 15
Number of OTUs	25.5	19.3	19.5	8.55	0.80	0.61	0.75
Shannon diversity	2.3	1.9	1.9	0.43	0.45	0.31	0.47
Inverse Simpson’s diversity	9.0	4.8	6.2	2.74	0.31	0.31	0.25
Solid-associated microbes
Day 5
Number of OTUs	47.0	39.0	43.0	6.66	0.71	0.68	0.48
Shannon diversity	2.8	2.7	2.7	0.14	0.82	0.76	0.60
Inverse Simpson’s diversity	9.8	8.5	8.6	1.11	0.69	0.49	0.66
Day 10
Number of OTUs	49.8	40.8	38.5	6.11	0.48	0.28	0.68
Shannon diversity	2.9	2.8	2.9	0.13	0.78	0.83	0.54
Inverse Simpson’s diversity	10.0	10.6	13.3	1.68	0.37	0.20	0.61
Day 15
Number of OTUs	54.8	47.8	45.3	6.53	0.59	0.33	0.78
Shannon diversity	3.0	3.1	2.8	0.15	0.49	0.44	0.38
Inverse Simpson’s diversity	12.2	14.5	10.8	2.42	0.61	0.70	0.39

SEM, standard error of the means; L, linear; Q, quadratic.