Bio - Bio Project - European Soil Portal - Europa

higher values have obviously been found in the
biological area.
%
1.5
1.2
0.9
0.6
0.3
0.0
0-5 0-15 15-
30
0-5 0-15 0-30 0-5 0-15 0-30
Ca OR (biologic) Ca NU (manure) Ca NO (sludge)
organic carbon H N
Figure 17 - Values of organic carbon, hydrogen and nitrogen in soil
EUR 22245 EN (2006) Bio-Bio Project
42
4.7 Heavy metals
Heavy metals concentrations in soil at the three levels
of depth are reported in Table 2.
Is evident the difference of concentration observed for
all elements between the biological and manure areas
compared with the amended area. This is also due, in
first approximation, to the different soil typology.
It can be seen that the concentration of heavy metals in
the site Cascina Novella are well in agreement with
values found in all the soil of Pavia Province. On the
other hand, in the Pavia Province only a small
percentage of soils are amended with sewage sludge.
Table 2 - Concentration values of heavy metals and carbon in the 3 layers of soil
Site
Layer
depth
Al As Cd Cr Cu Hg Ni Pb Zn
Ca OR
(biologic)
Ca NU
(manure)
Ca NO
(sludge)
AM3
Corte Olona
cm % mg/kg mg/kg mg/kg mg/kg mg/kg mg/kg mg/kg mg/kg
0-5 4.68 6.7 0.22 33 12.1 0.04 18.7 18.3 61
0-15 4.55 6.4 0.27 32 12.2 0.04 19.4 18.5 61
15-30 4.69 9.7 0.33 34 13.1 0.05 20.4 17.4 61
0-5 4.62 9.2 0.3 32 12.8 0.05 21.8 15.1 53
0-15 4.07 7.5 0.24 31 11.2 0.04 18.2 16.9 57
0-30 4.56 9.8 0.31 31 11.8 0.05 22.3 15.4 52
0-5 7.32 20.6 0.84 58 28.5 0.08 34.5 29 88
0-15 6.94 21.0 0.79 61 30.2 0.09 32 22.7 84
0-30 7.13 22.4 0.79 59 30.8 0.08 34.4 24.6 95
mean
value
5.81 15.1 0.42 66 28.,0 0.08 42 22.3 84
% Uncertainty 3 10 15 8 8 24 8 9 7
The soils of the first two farmhouses are very similar.
In fact the distance among the two sites is about one
kilometre only, while the farmhouse Cascina Novella is
located around 30 km south-east.
This is confirmed by the average vlues of heavy metals
concentration found in the area of Corte Olona. In this
big area, greater than 40 km 2 , sludge or manure are
both used. Several industries are also present and their
influence in the environment, soil in our case, is
important. The concentration values are similar to
those found in Cascina Novella, with the exception of
cadmium whose concentration was double of what
found in the big area.
4.8 Dioxins
In Figure 18 are shown values of PCDD/Fs for the
three investigated areas, expressed in WHO-TEQ
(World Health Organization – Toxic Equivalent
Quantities). They were obtained by analysis of the
three soil layers.
Values with minor differences in concentration for
dioxins and furans (PCDD/F) have been found in the
biological and manure areas. As concern the vertical
profiles of concentration, a pretty constant value is
noticed through the soil column analyzed. This has
been found despite the facts that for soils the main
source of dioxins and furans is by atmospheric
depositions. The phenomenon is easily explainable,
because plowing in fact homogenizes soil until depth
of about 50 cm.
Is interesting to see that in the area where sewage
sludge is used, the concentration values are slightly
higher than what is found in the other two areas.