2.3. Volumetric water content and wet bulk density
The volumetric water content was continuously monitored
with TDR probes for the whole period of the research. These have
been calibrated for the studied soil in previous research (unpublished
data). Since, it is well known that the
field saturation is
generally lower than that obtained in laboratory (as discussed in
the results section), a reference mean value of saturated water
content, us, was
first chosen for each soil cylinder, by comparing
the measurements obtained from the TDR probes and the water
retention curves for the studied soil during previous research
(Castellini et al., 2014). This evaluation was carried out after some
rainfall events and infiltration tests in order to establish if the
theoretical values of full saturation obtained in the laboratory
could be achieved under
field conditions. Using this information,
an appropriate mean value of us was established for each
treatment (i.e., us = 0.46 cm3cm3 for C0, C5 and C10; us = 0.47
and 0.48 cm3cm3 for C20 and C30, respectively). The initial soil