Assessment of nitrate pollution in the Grand Morin aquifers (France): combined use of geostatistics and physically-based modelling

Title
Publication TypeJournal Article
Year of Publication2006
AuthorsFlipo, N, Jeannée, N, Poulin, M, Even, S, Ledoux, E
JournalEnvironmental Pollution
Volume146
Start Page241
Pagination15
Date Published03/2007
Keywordsaquifers, basin, groundwaters, kriging, nitrate fluxes, non-point source pollution, physically based modeling
Abstract
The objective of this work is to combine several approaches to better understand nitrate fate in the Grand Morin aquifers (2700 km2), part of the Seine basin. cawaqs results from the coupling of the hydrogeological model newsam with the hydrodynamic and biogeochemical model of river ProSe. Cawaqs is coupled with the agronomic model Stics in order to simulate nitrate migration in basins. First, kriging provides a satisfactory representation of aquifer nitrate contamination from local observations, to set initial conditions for the physically based model. Then associated confidence intervals, derived from data using geostatistics, are used to validate cawaqs results. Results and evaluation obtained from the combination of these approaches are given (period 1977–1988). Then cawaqs is used to simulate nitrate fate for a 20-year period (1977–1996). The mean nitrate concentrations increase in aquifers is 0.09 mgN L-1 yr-1, resulting from an average infiltration flux of 3500 kgN.km-2 yr-1.
DOI10.1016/j.envpol.2006.03.056