water content, ui, for each cylinder, was obtained a few minutes
before the infiltration experiments (by the simplified falling head
method described below), and the difference between saturated
and initial soil water content (Du = us
ui) was determined.
An evaluation of temporal evolution of wet bulk density (here
and after called BDw), corresponding to the specific soil water
content of the starting conditions (depending on the considered
soil cylinder, about 0.25 cm3cm3), was carried out in order to
detect quasi-steady soil condition for ponded infiltrations.
The soil cylinders remained in the
field exposed to the natural
weather conditions for about 30 months, until BDw was nearly
constant. In detail, after each infiltration test and two natural
rainfall events and only after that the starting conditions of soil
water content have been reached, eight measurements of the
height difference between the soil surface and the top of the
cylinder were carried out at predetermined locations, and the
mean value was considered. Soil volume was determined by the
difference between the total volume and the upper empty space.
BDw of each cylinder was determined by dividing the known wet
mass of soil added by the actual soil volume. This provided a mean
value for the entire cylinder, assuming that there was no change in
soil mass during the period of the experiment. BDw was then
determined between March 2011 and September 2013.
water content, ui, for each cylinder, was obtained a few minutesbefore the infiltration experiments (by the simplified falling headmethod described below), and the difference between saturatedand initial soil water content (Du = usui) was determined.An evaluation of temporal evolution of wet bulk density (hereand after called BDw), corresponding to the specific soil watercontent of the starting conditions (depending on the consideredsoil cylinder, about 0.25 cm3cm3), was carried out in order todetect quasi-steady soil condition for ponded infiltrations.The soil cylinders remained in thefield exposed to the naturalweather conditions for about 30 months, until BDw was nearlyconstant. In detail, after each infiltration test and two naturalrainfall events and only after that the starting conditions of soilwater content have been reached, eight measurements of theheight difference between the soil surface and the top of thecylinder were carried out at predetermined locations, and themean value was considered. Soil volume was determined by thedifference between the total volume and the upper empty space.BDw of each cylinder was determined by dividing the known wetmass of soil added by the actual soil volume. This provided a meanvalue for the entire cylinder, assuming that there was no change insoil mass during the period of the experiment. BDw was thendetermined between March 2011 and September 2013.
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