In order to investigate the influence of the soil vertical nonhomogeneity on the dynamics of the water in the upper soil layer, an analytical solution of the linearized Richards equation was derived. Here the hydraulic conductivity Ks at saturation is assumed to decrease exponentially with depth, in accordance with field data reported in the literature and collected during our surveys in mountain catchments. Gardner’s constitutive laws were assumed for the hydraulic conductivity and water retention characteristics K(s) and Y(s). The resulting one-dimensional Richards equation is linear, and its coefficients decrease exponentially with depth. An analytical solution was found by using the method of Laplace transform and compared with some test cases both analytically and numerically. The soil water content profile exhibits a maximum at one point in the domain. Moreover, it accounts for a different behavior in the water dynamics, depending on the prevailing role of diffusive effects, related to the soil water retention, or of the transport effects, related to the hydraulic conductivity profile.

Water dynamics in a gradually nonhomogeneous soil described by the linearized Richards equation

BARONTINI, Stefano;RANZI, Roberto;BACCHI, Baldassare
2007-01-01

Abstract

In order to investigate the influence of the soil vertical nonhomogeneity on the dynamics of the water in the upper soil layer, an analytical solution of the linearized Richards equation was derived. Here the hydraulic conductivity Ks at saturation is assumed to decrease exponentially with depth, in accordance with field data reported in the literature and collected during our surveys in mountain catchments. Gardner’s constitutive laws were assumed for the hydraulic conductivity and water retention characteristics K(s) and Y(s). The resulting one-dimensional Richards equation is linear, and its coefficients decrease exponentially with depth. An analytical solution was found by using the method of Laplace transform and compared with some test cases both analytically and numerically. The soil water content profile exhibits a maximum at one point in the domain. Moreover, it accounts for a different behavior in the water dynamics, depending on the prevailing role of diffusive effects, related to the soil water retention, or of the transport effects, related to the hydraulic conductivity profile.
File in questo prodotto:
File Dimensione Formato  
2007_Barontini_etal@WRR_Richards.pdf

gestori archivio

Tipologia: Altro materiale allegato
Licenza: DRM non definito
Dimensione 509.92 kB
Formato Adobe PDF
509.92 kB Adobe PDF   Visualizza/Apri   Richiedi una copia

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11379/25161
 Attenzione

Attenzione! I dati visualizzati non sono stati sottoposti a validazione da parte dell'ateneo

Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 17
  • ???jsp.display-item.citation.isi??? 17
social impact