TABLE 2.

Variation partitioning of the effect of soil depth (0–15 vs. 15–30 cm) on soil prokaryotic and fungal diversity at different phylogenetic resolution in a wheat-soybean rotation in the Mediterranean area.

	0–15 vs. 15–30 cm
	Variance explained
Prokaryotes at class level
Soil depth a	36.87 b
TIL	5.90
N fert	7.14
Prokaryotes at phylum level
Soil depth	10.32
TIL	5.10
N fert	5.78
Fungi at family level
Soil depth	21.21
TIL	7.47
N fert	7.19
Fungi at phylum level
Soil depth	–
TIL	–
N fert	–

Tillage and nitrogen fertilization were used as covariates. ^aPermutational analyses of variance were performed using soil depth as fixed factor, tillage (TIL) and nitrogen fertilization (N fert) as covariates and 12 replicates plots per soil depth. TIL, minimum tillage and conventional tillage; N fert: 0 kg N ha^–1 and 200 kg N ha^–1. ^bIn bold statistically significant values (P ≤ 0.05).