Bioavailability and Solubility of Heavy Metals and Trace Elements during Composting of Cow Manure and Tree Litter

Table 8

Positive values of Pearson’s correlation between primary variables and the AH with significance without influence of the inoculation factor.

Primary variable (mg·kg^−1)	Secondary physicochemical variable (%)	N	Pearson	value
[Cd]tot	HA	30	0.5176	3.40 × 10^−3
[Cr]tot	HA	30	0.5788	8.06 × 10^−4
[Ni]tot	HA	30	0.5864	6.61 × 10^−4
[Mo]DTPA	HA	30	0.6223	2.41 × 10^−4
[Pb]tot	HA	30	0.6254	2.19 × 10^−4
[Hg]tot	HA	30	0.6633	6.47 × 10^−5
[Zn]tot	HA	30	0.7385	3.18 × 10^−6
[Se]tot	HA	30	0.8024	9.65 × 10^−8

[·] total concentration; [·]_DTPA: concentration extracted with pentatetic acid; [·]_H2O: concentration extracted with deionized water; HA: fraction of humic acids.