Table 3. Analysis of variance (ANOVA) P values for cumulative decomposition rate, percentage residue decomposed, decay constant (k) and associated parameters over 50-days’ laboratory incubation study for barley residue decomposition conducted at the Aberdeen Research and Extension Center, Aberdeen, ID, USA.

Sources of variation	Cumulative CO2-C decomposition	Residue decomposed	Decay constant (k)	t(0.5)	t(0.75)	t(0.99)
Residue placement (RP)	<0.001	<0.001	<0.001	<0.001	<0.001	<0.001
Residue size (RS)	<0.001	<0.001	<0.001	<0.001	<0.001	<0.001
Soil type (ST)	0.09	0.09	0.34	0.07	0.23	0.09
RP x RS	<0.001	<0.001	<0.001	<0.001	<0.001	<0.001
RP x ST	0.17	0.16	0.07	0.18	0.09	0.20
RS x ST	0.10	0.10	0.66	0.13	0.72	0.12
RP x RS x ST	0.24	0.27	0.09	0.35	0.10	0.41