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

Table 3

Heavy metals and trace elements of interest of the raw materials used in the evaluation stage composting (n = 6).

Total contents of heavy metals and of trace elements of interest (HMtot)	Tree litter (TREE-L)	Cattle manure (COW-M)
	P 1-6 (Mean ± St. Dev.)	P 1-6 (Mean ± St. Dev.)
As (mg·kg^−1)	28.17 ± 3.13	8.83 ± 2.93
Cd (mg·kg^−1)	1.29 ± 0.05	0.34 ± 0.03
Cr (mg·kg^−1)	26.50 ± 3.02	6.33 ± 1.03
Cu (mg·kg^−1)	49.00 ± 4.00	94.67 ± 27.85
Hg (mg·kg^−1)	0.30 ± 0.03	0.06 ± 0.02
Mo (mg·kg^−1)	4.46 ± 0.82	4.27 ± 0.17
Ni (mg·kg^−1)	7.18 ± 0.57	3.13 ± 0.32
Pb (mg·kg^−1)	59.00 ± 5.34	9.43 ± 1.60
Se (mg·kg^−1)	0.56 ± 0.04	1.41 ± 0.45
Zn (mg·kg^−1)	268.00 ± 17.57	313.00 ± 70.24