Nursery Growing Media: Agronomic and Environmental Quality Assessment of Sewage Sludge-Based Compost

Table 2

Physical and physicochemical characteristics of sewage sludge compost.

Parameters	Value in sewage sludge compost (SSC)	Limit values in SSC (according to Italian Legislation Lgs D. 75/2010)
Colour	10YR 3/2
Moisture content (%)	44.4	≤50.0
Total OM (%)^a	58.6	—
Oxidizable OC (%)^a	29.0	≥20.0
C : N ratio	10.2	≤25.0
CHA/CFA	1.96	—
Total Kjeldahl Nitrogen TKN (%)^a	2.83	—
P2O5 (%)^a	0.91	—
K2O (%)^a	0.71	—
CEC (cmol^(+) kg^−1)	77.0	—
Pb (%)^a	6.40	140
Cd (%)^a	0.10	1.50
Ni (%)^a	3.20	100
Zn (%)^a	394	500
Cu (%)^a	14.1	230
Hg (%)^a	0.10	1.50
Cr^+6 (%)^a	0.10	0.50

aValues on a dry matter basis; data are mean values, 𝑛=3.