Phosphorus availability in relation to soil properties and forest productivity in Pinus sylvestris L. plantations

Table 6 Pearson’s correlations between P fractions and physical, chemical, and biochemical parameters in soils and site index (“-” means not significant)

	P_AEM	log(P_iNaHCO₃)	√(P_oNaHCO₃)	log(P_iNaOH)	P_oNaOH	log(PHCl_1M)	P_rec
pH	0.50**	-	-	-		0.51**	0.50**
EOC	-			0.44**		-	-
EA	-	-	-	0.53**	-	-	-
log(Ca²⁺)	0.73***	-	-	-	0.46**	0.62***
Al_E	− 0.46**	-	-	-	-	− 0.46**	-
Fe_A	-	-	0.54**	0.45**	0.60***	-	-
Cmic	0.70***	0.53**	-		0.54**	0.47**
√Pmic	0.60***		0.49**		0.60***	0.44**	0.44**
log(Cmin)	-	-	-	− 0.51**	-	-	-
Site index	-	0.54***		0.58***	0.47**	0.50**	-

**P < 0.01; ***P < 0.001. P_AEM, available P; P_iNaHCO₃, P_oNaHCO₃, highly labile inorganic and organic P; P_iNaOH, P_oNaOH, moderately labile inorganic and organic P; PHCl_1M, primary P; P_rec, recalcitrant P; EOC, easily oxidizable C; EA, exchangeable acidity; Fe_A, Fe within amorphous Fe oxyhydroxides; Al_E, exchangeable Al; Cmic, microbial biomass C; Pmic, microbial biomass P; Cmin, mineralizable C

ISSN: 1297-966X