The evolution in time, t, of the experimental soil moisture vertical profile, observed in natural fields together with associated hydrometeorological quantities, is investigated by a conceptual model to put in evidence and then to simulate the involved processes. The measurements were carried out in two plots located in Perugia, Central Italy. The soil water content, θ, was continuously monitored at different depths, z, using a Time Domain Reflectometry (TDR) system. Four buriable three-rod waveguides were inserted horizontally at the depths 5, 15, 25 and 35 cm, furthermore sensors of air temperature and relative humidity, wind speed, solar radiation, evaporation and rain were operative. A plot characterized by grassland over a sandy soil and an adjacent plot with a bare silty loam soil, both equipped with similar sensors, were simultaneously considered. A conceptual model, developed by Corradini et al. (2000), has been used to simulate the evolution in time of the soil moisture vertical profile during rainfall infiltration and successive redistribution/evapotranspiration periods in each plot. We have found that the commonly used models for continuous simulations of θ(z, t) have to be improved by taking into account the variability in time of the saturated hydraulic conductivity that is due, for bare soils, to the processes of formation and disruption of a sealing layer over the original parent soil and, for grassy soils, to the formation of a two-layered vertical profile with a more permeable upper layer associated to vegetation growth.
On the evolution in time of the soil moisture vertical profile in two natural plots
FLAMMINI, ALESSIA;ROSSI, ERIKA;CORRADINI, Corrado;SALTALIPPI, Carla;MORBIDELLI, Renato
2012
Abstract
The evolution in time, t, of the experimental soil moisture vertical profile, observed in natural fields together with associated hydrometeorological quantities, is investigated by a conceptual model to put in evidence and then to simulate the involved processes. The measurements were carried out in two plots located in Perugia, Central Italy. The soil water content, θ, was continuously monitored at different depths, z, using a Time Domain Reflectometry (TDR) system. Four buriable three-rod waveguides were inserted horizontally at the depths 5, 15, 25 and 35 cm, furthermore sensors of air temperature and relative humidity, wind speed, solar radiation, evaporation and rain were operative. A plot characterized by grassland over a sandy soil and an adjacent plot with a bare silty loam soil, both equipped with similar sensors, were simultaneously considered. A conceptual model, developed by Corradini et al. (2000), has been used to simulate the evolution in time of the soil moisture vertical profile during rainfall infiltration and successive redistribution/evapotranspiration periods in each plot. We have found that the commonly used models for continuous simulations of θ(z, t) have to be improved by taking into account the variability in time of the saturated hydraulic conductivity that is due, for bare soils, to the processes of formation and disruption of a sealing layer over the original parent soil and, for grassy soils, to the formation of a two-layered vertical profile with a more permeable upper layer associated to vegetation growth.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
