Table 3.

Effect of incubation on the numbers of ammonia-oxidizing archaea and bacteria and their mutual ratio according to a nonparametric Kruskal-Wallis test.

	Year of sampling	N	Degrees of freedom	H	p	Remarks
log AOA	2009	55	1	7.044	0.0080	day 6 > day 0
	2010	59	1	15.603	0.0001	day 6 < day 0
log AOB	2009	53	1	9.284	0.0023	day 6 > day 0
	2010	59	1	0.568	0.4439	day 6 > day 0
log AOA/AOB	2009	50	1	2.992	0.0837	day 6 < day 0
	2010	58	1	5.126	0.0236	day 6 < day 0