TABLE 2.

Characteristics of 5- to 10-cm-depth horizon soil under Norway spruce, oak, and beech at the Breuil-Chenue experimental site^a

Tree species	Environmentb	pHc	meq 100 g−1d			g kg soil−1		C/N ratio
			K	Mg	Ca	N	C
Beech	R	4.47	0.79	0.29	0.30	5.52	90	16.23
	BS	4.48	0.36	0.20	0.23	4.48	74	16.55
Oak	R	4.35	1.57	0.40	0.29	4.94	83	16.85
	BS	4.32	0.61	0.26	0.17	4.01	68	16.93
Spruce	R	4.14e	0.68	0.41	0.28	4.92	87	17.61
	BS	4.30	0.42	0.21	0.15	4.12	72	17.49

^aData are from the work of Mareschal (34).

^bR, rhizosphere; BS, bulk soil.

^cSoil pH was measured in H₂O with a soil-to-solution ratio of 1:2.

^dMilliequivalent for 100 g of fine earth (dry weight).

^eThe pH of the spruce rhizosphere is significantly more acidic than those of the other soils environments according to a one-factor (tree-species) ANOVA (P = 0.05) and the Bonferroni-Dunn test (adapted from the work of Calvaruso et al., 2009 [11]).