In the framework of the Mesoscale Alpine Programme (MAP), soil water content
profiles were collected at a point station in the Toce Valley (Lago Maggiore MAP Target
Area). The data are for the first 70 cm depth of soil for the period April–November, 1999.
All measurements were made by a Time Domain Reflectometry device. The time variation of
the water stored in a column of soil was estimated by a mass balance method. Evaporation
was estimated from the data collected in the summer period. Likewise, by applying the mass
balance method to the data collected during and after heavy precipitation events, the
water infiltrated into the soil was also estimated. A qualitative evaluation of ponding
and/or runoff as the difference between the precipitated and the drained water was obtained
under suitable assumptions. Furthermore, the time evolution of the soil water content
profile was studied by solving the Richards equation both analytically and numerically
for two particular cases: the driest period and a period following a heavy precipitation
event. Finally, during the MAP Special Observing Period, two intensive campaigns were
performed, together with measurements using an airborne passive microwave radiometer,
to assess the spatial distribution of the surface (0–30 cm depth) soil water content in
fields with different physical and agricultural characteristics.
Keywords: soil water content, Time Domain Reflectometry, TDR temperature-dependence,
evaporation, infiltration, runoff, linearised Richards equation. |