Skip to Main content Skip to Navigation
Journal articles

Improvement of the solute transfer in a conceptual unsaturated zone scheme : a case study of the Seine River Basin

Abstract : For predicting the evolution of solute concentrations in groundwater and testing the impact of remediation policies, a coupling between the agronomical model STICS and the hydrogeological model MODCOU was implemented. Applied to the Seine river basin, this model represents accurately the temporal evolution of average nitrate concentrations in the aquifer, but with large local errors. We propose an improvement of the simple unsaturated zone scheme NonsatSW used in STICS-MODCOU. The modifications are based on a comparison with the mechanistic model Metis considered as a reference as it solves Richards'equation. A more realistic saturation profile and a varying percolation rate are integrated in NonsatSW. This new model, named NonsatVG, is assessed by a comparison with NonsatSW and Metis. In an ideal case, NonsatVG generates a solute transfer and a dispersion closer to that of Metis than NonsatSW. In real cases, without additional calibration, NonsatVG and Metis simulate better the average transfer velocities of the observed nitrate profiles. Furthermore, modifications in NonsatVG give a direct link between the water table depth and the saturation profile. We obtain therefore, as in Metis, an evolution of the solute transfer velocity depending on the piezometric level. These dynamics are not simulated in NonsatSW. Despite a modified water transfer through the unsaturated zone, NonsatVG is also as valid as NonsatSW in the modelling of water transfer to the saturated zone. Finally, an application on the Seine basin show that solute transfer velocities are lower with NonsatVG than with NonsatSW, but in better agreement with literature.
Document type :
Journal articles
Complete list of metadata

Cited literature [38 references]  Display  Hide  Download

https://hal-mines-paristech.archives-ouvertes.fr/hal-00507039
Contributor : Pascale Nalon <>
Submitted on : Thursday, July 29, 2010 - 3:18:20 PM
Last modification on : Wednesday, December 9, 2020 - 3:05:15 PM
Long-term archiving on: : Thursday, November 4, 2010 - 10:34:31 AM

File

article_HP-Philippe-07-2010.pd...
Files produced by the author(s)

Identifiers

Citation

Florence Habets, Emmanuel Ledoux, Patrick Goblet, Pascal Viennot, Bruno Mary. Improvement of the solute transfer in a conceptual unsaturated zone scheme : a case study of the Seine River Basin. Hydrological Processes, Wiley, 2010, 25 (5), pp.752-765. ⟨10.1002/hyp.7865⟩. ⟨hal-00507039⟩

Share

Metrics

Record views

540

Files downloads

726