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| Titel |
Estimation of the water retention curve from the soil hydraulic conductivity
and sorptivity in an upward infiltration process |
| VerfasserIn |
David Moret-Fernández, Marta Angulo, Borja Latorre, César González-Cebollada, María Victoria López |
| Konferenz |
EGU General Assembly 2017
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| Medientyp |
Artikel
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| Sprache |
en
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 19 (2017) |
| Datensatznummer |
250143341
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| Publikation (Nr.) |
 EGU/EGU2017-7050.pdf |
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| Zusammenfassung |
| Determination of the saturated hydraulic conductivity, Ks, and the α and n parameters of the
van Genuchten (1980) water retention curve, θ(h), are fundamental to fully understand and
predict soil water distribution. This work presents a new procedure to estimate the soil
hydraulic properties from the inverse analysis of a single cumulative upward infiltration curve
followed by an overpressure step at the end of the wetting process. Firstly, Ks is calculated
by the Darcy’s law from the overpressure step. The soil sorptivity (S) is then estimated using
the Haverkamp et al., (1994) equation. Next, a relationship between α and n, f(α,n), is
calculated from the estimated Sand Ks. The α and n values are finally obtained by the
inverse analysis of the experimental data after applying the f(α,n) relationship to the
HYDRUS-1D model. The method was validated on theoretical synthetic curves for three
different soils (sand, loam and clay), and subsequently tested on experimental sieved soils
(sand, loam, clay loam and clay) of known hydraulic properties. A robust relationship was
observed between the theoretical α and nvalues (R2 > 0.99) of the different
synthetic soils and those estimated from inverse analysis of the upward infiltration
curve. Consistent results were also obtained for the experimental soils (R2 >
0.85). These results demonstrated that this technique allowed accurate estimates
of the soil hydraulic properties for a wide range of textures, including clay soils. |
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