title: Evaluation of a spatialized agronomic model in predicting yield and N leaching at the scale of the Seine-Normandie Basin.
abstract: The EU directive has addressed ambitious targets concerning the quality of water bodies. Predicting water quality as affected by land use and management requires using dynamic agro-hydrogeological models. In this study, an agronomic model (STICS) and a hydrogeological model (MODCOU) have been associated in order to simulate nitrogen fluxes in the Seine-Normandie Basin, which is affected by nitrate pollution of groundwater due to intensive farming systems. This modeling platform was used to predict and understand the spatial and temporal evolution of water quality over the 1971-2013 period. A quality assurance protocol (Refsgaard et al. Environ Model Softw 20: 1201-1215, 2005) was used to qualify the reliability of STICS outputs. Four iterative runs of the model were carried out with improved parameterization of soils and crop management without any change in the model. Improving model inputs changed much more the spatial distribution of simulated N losses than their mean values. STICS slightly underestimated the crop yields compared to the observed values at the administrative district scale. The platform also slightly underestimated the nitrate concentration at the outlet level with a mean difference ranging from -1.4 to -9.2 mg NO3L-1according to the aquifer during the last decade. This outcome should help the stakeholders in decision-making to prevent nitrate pollution and provide new specifications for STICS development.
authors.affiliation: INRA, UR 1158 Agro-Impact, site de Laon, Pôle du Griffon, F-02000, Barenton-Bugny, France. nicolas.beaudoin@laon.inra.fr.
authors.forename: N
authors.initials: N
authors.lastname: Beaudoin
authors.affiliation: MINES ParisTech/ARMINES, PSL Research University, Centre de Géosciences, 35 rue St-Honoré, F-77305, Fontainebleau, France.
authors.forename: N
authors.initials: N
authors.lastname: Gallois
authors.affiliation: MINES ParisTech/ARMINES, PSL Research University, Centre de Géosciences, 35 rue St-Honoré, F-77305, Fontainebleau, France.
authors.forename: P
authors.initials: P
authors.lastname: Viennot
authors.affiliation: INRA-US 1106 Infosol, 2163 avenue de la Pomme de Pin, F-45075, Orléans, France.
authors.forename: C
authors.initials: C
authors.lastname: Le Bas
authors.affiliation: INRA SAD, Unité Aster, 662 avenue Louis Buffet, F-88500, Mirecourt, France.
authors.forename: T
authors.initials: T
authors.lastname: Puech
authors.affiliation: INRA SAD, Unité Aster, 662 avenue Louis Buffet, F-88500, Mirecourt, France.
authors.forename: C
authors.initials: C
authors.lastname: Schott
authors.affiliation: UMR INRA - UMR 1114 EMMAH, Domaine Saint Paul, F-84914, Avignon, Cedex 9, France.
authors.forename: S
authors.initials: S
authors.lastname: Buis
authors.affiliation: INRA, UR 1158 Agro-Impact, site de Laon, Pôle du Griffon, F-02000, Barenton-Bugny, France.
authors.forename: B
authors.initials: B
authors.lastname: Mary
mesh_terms: D000383:Agriculture / Q000379:methods; D018556:Crops, Agricultural; D004784:Environmental Monitoring / Q000379:methods; D005602:France; D060587:Groundwater; D062070:Hydrology / Q000379:methods; D008962:Models, Theoretical; D009566:Nitrates / Q000032:analysis; D009584:Nitrogen / Q000032:analysis*; D015203:Reproducibility of Results; D012987:Soil / Q000737:chemistry; D012989:Soil Pollutants / Q000032:analysis; D062211:Spatio-Temporal Analysis; D014874:Water Pollutants, Chemical / Q000032:analysis; D060753:Water Quality
chemical_list: D009566:Nitrates; D012987:Soil; D012989:Soil Pollutants; D014874:Water Pollutants, Chemical; D009584:Nitrogen
keywords: Cropping system; MODCOU; Nitrate pollution; Nitrogen leaching; Quality assurance; STICS; Water drainage