However, BDw was
estimated at the same soil wetness value using TDR probes (Fig. 1),
and several reasons of expediency have suggested the choice of
BDw rather than rb: (i) to dry
first and then to weigh about 450 kg
of soil was not a feasible solution as it would require long times in
the laboratory; (ii) since it is expected that “wet” and “dry” soil
bulk density are correlated, the use of these two soil properties is
equivalent if the aim is to identify quasi-steady and comparable
soil conditions among treatments for infiltration tests; (iii) an
accurate estimate of rb of the soil layer subject to the Kfs
measurements (15 cm of depth) was carried out at the end of the
research (as reported in the following sections). Furthermore the
detected differences among treatments were quite low or
practically negligible for comparison purposes. According to a
two-tailed t-test, the BDw differences were not statistically
significant. Since both quasi-steady and comparable BDw values
were established, any Kfs discrepancies among treatments (within
each sampling date or among different dates) cannot be attributed
to different compaction of the soil.
Table