Table 4. Influence of carbon source and C/N ratio on Gompertz parameters of cumulative methane yield during anaerobic digestion at 18 d

Carbon source	C/N ratio	M (N mL / g VS)	P (N mL / g VS)	Rm (N mL / g VS / day)	λ (days)
Starch	10	191.3	198.4	20.1	2.7
	25	191.8	205.2	18.1	3.0
	40	187.1	199.2	18.8	3.2
Cellulose	10	195.3	217.0	16.3	3.3
	25	203.1	237.5	15.2	3.3
	40	233.0	223.2	14.5	3.5
Xylan	10	196.7	201.3	20.9	2.2
	25	197.6	210.4	19.5	2.5
	40	195.8	208.5	18.6	2.3
SEM		5.12	5.61	0.77	0.23
p-value1)	C	0.123	0.001	0.001	0.000
	CN	0.627	0.022	0.020	0.304
	C × CN	0.932	0.600	0.815	0.762

C, effect of carbon type; CN, effect of carbon: nitrogen ratio; C × CN, interaction between carbon type and carbon: nitrogen ratio.
C/N ratio, carbon to nitrogen ratio.