Table 4. Correlations between methanogenic archaeal and methanotrophic bacterial community similarity and the presence of Azolla or cultivation period of early-rice.

Domain			based on OTU level			based on Genus level
	Grouping		ANOSIM R statistic	ANOSIM P-value	Significant?	ANOSIM R statistic	ANOSIM P-value	Significant?
Methanogens	Azolla (with or without Azolla)		0.125	0.072	No	0.278	0.013	Yes
	Cultivation period	17d × 47d	0.222	0.048	Yes	0.296	0.037	Yes
		17d × 67d	0.502	0.002	Yes	1	0.002	Yes
		47d × 67d	0.7	0.002	Yes	0.4	0.015	Yes
Methanotroph	Azolla (with or without Azolla)		0.352	0.003	Yes	0.187	0.047	Yes
	Cultivation period	17d × 47d	0.7	0.002	Yes	0.4	0.006	Yes
		17d × 67d	0.7	0.002	Yes	0.967	0.002	Yes
		47d × 67d	0.1	0.21	No	0.328	0.024	Yes

A 999 permutations of the test for each ANOSIM analysis (higher than possible permutations). A test is considered significant if P < 0.05.