Stéphanie Veran-Tissoires, Manuel Marcoux, Marc Prat - Institut National Polytechnique de Toulouse (INPT), Institut de Mécanique des Fluides de Toulouse (IMFT), UMR 5502 CNRS-UPSToulouseFrance
Heterogeneity in soil hydraulic properties has a significant impact on evaporation, and could be harnessed to reduce water losses and improve soil water conservation. This is illustrated through the consideration of the effect of Darcy scale heterogeneities resulting from horizontal layering. The impact of permeability gradient and thickness of layers has been investigated from evaporation experiments performed from homogeneous as well as horizontally multi-layered soil columns. Two main cases are distinguished depending on the sign of the permeability gradient, the unstable case when the permeability increases with depth and the stable case when, on the contrary, the permeability decreases with depth. The results indicate an interesting competition between stabilizing gravity effects and destabilizing or stabilizing permeability gradient effects and lead to the emergence of the concept of two-scale evaporation process.
Stéphanie Veran-Tissoires, Manuel Marcoux, Marc Prat - Institut National Polytechnique de Toulouse (INPT), Institut de Mécanique des Fluides de Toulouse (IMFT), UMR 5502 CNRS-UPSToulouseFrance
Heterogeneity in soil hydraulic properties has a significant impact on evaporation, and could be harnessed to reduce water losses and improve soil water conservation. This is illustrated through the consideration of the effect of Darcy scale heterogeneities resulting from horizontal layering. The impact of permeability gradient and thickness of layers has been investigated from evaporation experiments performed from homogeneous as well as horizontally multi-layered soil columns. Two main cases are distinguished depending on the sign of the permeability gradient, the unstable case when the permeability increases with depth and the stable case when, on the contrary, the permeability decreases with depth. The results indicate an interesting competition between stabilizing gravity effects and destabilizing or stabilizing permeability gradient effects and lead to the emergence of the concept of two-scale evaporation process.