Analyse cartographique de données pédologiques et hydrogéologiques appliquée à la gestion responsable de produits phytosanitaires

BASF launched a Responsible Bentazone Management plan in 2011, in order to preserve water resources and sustain its bentazon based herbicide solutions. This molecule is commercialized by the company for several years and is found at concentrations above the standard for drinking water in about 1% of groundwater catchments in France. The action plan aims to reduce contamination situations with recommendations on the use of bentazone (dose, timing of application, restrictions on vulnerable soils on groundwater catchment areas) that complement the commercialization authorization. The study carried out during the internship focused on the diagnosis of a groundwater catchment area located in the Jura with significant contamination of groundwater by bentazon. The objective was to develop a mapping, soil and hydrogeological approach to diagnosis and to compare the recommendations for use of "Responsible Care" BASF with concrete field data. The objective was to develop a mapping, soil and hydrogeological approach to diagnosis and to compare the recommendations on the use of bentazone provided by BASF with concrete field data. This involved the collection of various documents and data from local and national actors and the realization of a survey of farmers present in the study area to acquire field data. The study showed that some parcels are subject to rising from the groundwater at a low depth and have a heavy clay texture. This results in a sharp soil waterlogging that leads to the solubilisation of bentazone in soil which is then transferred to groundwater. This has confirmed the relevance of the non-using recommendation of bentazon on parcels with presence of shallow water. The study also showed that the problem of contamination seems more linked to local soil and hydrogeological parameters than to physico-chemical properties of the molecules used. ; BASF a lancé un plan de Gestion Responsable de la Bentazone en 2011, dans le but de préserver les ressources en eau et de pérenniser ses solutions herbicides à base de ...