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International audience; Over the past seventy years, some herbicides have become “keystone” active ingredients in weed management. In France, until 2003, atrazine played a key role for maize weeding. Since 1974, glyphosate has become the most used herbicide for intercropping period management and has become central for conservation agriculture. Such exceptional efficiency and a low cost placed atrazine and glyphosate among the most used herbicides worldwide. In either case, their over-use has contributed to water pollution and to the emergence of questions about possible negative effects on the environment. An agronomical, economical and societal comparison between the withdrawal of atrazine and glyphosate showed similar concerns of agricultural sector about weed management. The withdrawal of atrazine may have increased costs of maize weeding, but weed communities have been successfully managed, mainly thanks to the use of other chemical ingredients. The possible glyphosate ban, planned in France in a near future, may have strong impacts on weed management and more generally on farm operations. The main available alternative to glyphosate is soil tillage, but other agronomical practices have to be associated to maintain an effective weed management. Although 15 years apart, the withdrawal of these two active ingredients allows to put emphasis on the impacts that a massive use of a unique chemical ingredient can have on the environment and on the adaptability of agricultural systems.; Au cours de ces 70 dernières années, certaines substances actives herbicides ont acquis le statut de molécules « pilier » dans la gestion des communautés adventices. En France, jusqu’en 2003, l’atrazine a joué un rôle central dans le désherbage du maïs. Depuis 1974, le glyphosate est devenu la molécule la plus utilisée dans la gestion de l’interculture, au point d’être considéré comme indispensable en agriculture de conservation. Une excellente efficacité et un faible coût ont placé ces deux molécules parmi celles les plus utilisées au monde. Mais dans les deux cas, une utilisation trop importante a conduit à la contamination des eaux et à l’émergence de questionnements sur de possibles effets négatifs sur l’environnement. Une comparaison de l’interdiction de l’atrazine et du glyphosate, d’un point de vue agronomique, économique et social, montre des inquiétudes similaires sur la gestion de la flore adventice de la part de la profession agricole. Si le retrait de l’atrazine a pu engendrer une augmentation des coûts de désherbage du maïs, la flore adventice a su être correctement maîtrisée via la mobilisation d’autres leviers, principalement chimiques. L’interdiction potentielle du glyphosate, prévue en France dans un futur proche, pourrait avoir des conséquences fortes sur la gestion de la flore adventice et plus globalement sur les exploitations agricoles. Le principal levier disponible pour se passer de glyphosate est le recours au travail du sol, mais d’autres leviers agronomiques doivent venir en complément pour assurer une gestion efficace. Bien que séparé de 15 années, le retrait de ces deux substances actives est l’occasion de prendre conscience des conséquences que peut avoir l’utilisation prédominante d’une unique substance active sur l’environnement, mais aussi sur la capacité d’adaptation des systèmes agricoles.

International audience; Faced with health, environmental, and socio-economic issues related to the heavy use of pesticides, diffuse phytosanitary pollution becomes a major concern shared by all the field actors. These actors, namely the farmers and territorial managers, have expressed the need to implement decision support tools for the territorial management of diffuse pollution resulting from the plant protection practices and their impacts. To meet these steadily increasing requests, a cartographic analysis approach was implemented based on GIS which allows the spatialization of the diffuse pollution impacts related to plant protection practices on the Etang de l’Or catchment area in the South of France. Risk mapping represents a support-decision tool that enables the different field actors to identify and locate vulnerable areas, so as to determine action plans and agri-environmental measures depending on the context of the natural environment. This work shows that mapping is helpful for managing risks related to the use of pesticides in agriculture by employing indicators of pressure (TFI) and risk on the applicator’s health (IRSA) and on the environment (IRTE). These indicators were designed to assess the impact of plant protection practices at various spatial scales (field, farm, etc.). The cartographic analysis of risks related to plant protection practices shows that diffuse pollution is unequally located in the North (known for its abundant garrigues and vineyards) and in the South of the Etang de l’Or catchment area (the Mauguio-Lunel agricultural plain known for its diversified cropping systems). This spatial inequity is essentially related to land use and agricultural production system. Indeed, the agricultural lands cover about 60% of the total catchment area. Consequently, this cartographic analysis helps the territorial actors with the implementation of strategies for managing risks of diffuse pollution related to pesticides use in agriculture, based on environmental and socio-economic issues and the characteristics of the natural environment.

Synthesis note. ENPARD South initiative (European Commission)

Existe en version française et anglaise; International audience; The widespread use of antimicrobials in agriculture is increasing, driven by growth in intensive livestock production and demand for animal products. This is creating a serious problem of antimicrobial resistance: bacteria are developing antimicrobial resistance mechanisms, which spread through populations of bacteria, including those affecting humans. Antimicrobial resistance has a major impact on public health, and its effects on animal health and biodiversity are not yet fully understood. To address this alarming situation, reducing and rationalising the use of antimicrobials is a global priority, in the North and the South alike. This calls for intersectoral actions involving professionals and researchers from many different scientific fields: domestic animals, wildlife, plants, humans and the environment. Implementing such actions is particularly complex in the countries of the South.; L’usage massif des antibiotiques en agriculture augmente avec l’essor des élevages intensifs et de la demande en produits animaux. Un phénomène grave en résulte, l’antibiorésistance : des bactéries développent des mécanismes de résistance aux antibiotiques, résistance qui se diffuse dans les populations bactériennes, y compris celles affectant l’homme. L’antibiorésistance a un impact majeur sur la santé publique, et ses effets sur la santé animale et la biodiversité sont encore mal connus. Face à ce fléau, réduire et rationaliser l’usage des antibiotiques est une urgence mondiale, au Nord comme au Sud. Cela requiert des actions intersectorielles impliquant les professionnels et les chercheurs dans de multiples domaines des sciences : les animaux domestiques, la faune sauvage, les plantes, l’homme et l’environnement. Ces actions sont particulièrement complexes à mettre en œuvre dans les pays du Sud.

International audience; Diffuse phytosanitary pollution is a complex phenomenon to manage. Reducing this type of pollution is one of today’s key socio-economic and environmental challenges. At the regional level, few approaches enable the actors concerned to implement agricultural management strategies to reduce the use and impact of phytosanitary products. Our research problem focused on the consequences of intensive agriculture and, in particular, how to evaluate the impact of phytosanitary products on human health and the environment. In this article, we present the SimPhy simulation game which places the actors from a given region directly into a situation in which they manage farms whilst under pressure to reduce phytosanitaries (quantity and toxicity). The application focused on the Merja Zerga catchment area in Morocco. The region is dominated by intensive agriculture which is located upstream from a Ramsar-classified wetland area. The SimPhy simulation game is based on a decision support system-type tool. It allows us to anticipate the impact of regulations on farming systems. It also enables us to analyse the consequences of the actors’ strategies on farm economies, human health and the quality of ecosystems. Initial results from the SimPhy simulation game enabled the technicians from Agricultural Development Center (CDA) themselves to learn about managing agricultural production systems in a dynamic and interactive fashion. With the simulation game, it was possible to learn about the farmer's ability to adapt to new regulatory constraints, and the involved consequences for toxicity risks for human health and the environment.

Communication orale; National audience

Communication orale : résumé étendu. Session 1 : Approches innovantes pour la réduction des doses appliquées; International audience

Communication orale : résumé. Session 4 : Risques liés aux usages de pesticides; International audience

International audience

The pollution and depletion of our groundwater resources is one of the biggest threats to our society. In recent times, groundwater has been facing an increasing pressure from intensive land use (e.g. agriculture, industry, forestry, etc) and overconsumption by people. In many areas of the world the quantity and quality of groundwater aquifers has been negative affected; causing harm to both humans and the environment. This paper has been written in connection with the Genesis project, which aims to identify threats to groundwater and groundwater dependent ecosystems, to increase the knowledge in relation to groundwater systems, to develop new tools and indicators for a better groundwater management and to give a new scientific foundation for the revision of the groundwater directive (GWD). The main focus of this thesis lies on the risk assessment, in relation to groundwater contamination caused by pesticides, under Norwegian conditions. Here, a risk evaluation was undertaken by means of the risk indicator model (EPRIP); and for the area Grue, a small municipality located in the south-eastern part of Norway. Simulations were done for potato and spring wheat production, a total of 9 different soil types and 44 pesticides. Active ingredients were then grouped in (1) risk classes according to the final EPRIP score and (2) risk classes according to predicted environmental concentration in groundwater and hydrological class. The results were so compared with field data and risk classifications obtained by MACRO_GV (for the same area), in order to validate the outcomes and to identify whether EPRIP is suitable for Norwegian conditions or not. Due to large difference between the predicted environmental concentrations (PEC) in groundwater, achieved by MACRO_GV and EPRIP; calibrations (in relation to water table thickness and water table depth) were undertaken for last named model. This has been done in order to ensure a better foundation for the comparison of the two models, by reason of the different approaches they use for the calculation of the PEC in groundwater. Due to limited time, four active ingredients were chosen in order to monitor the effects of the calibration; those were MCPA, metribuzin, tribenuron-methyl and rimsulfuron. Parameters were adjusted gradually; meaning that simulations were done for (1) a water table thickness of 0.3 m, (2) a water table depth of 1 m, and (3) a change in both parameters simultaneously. Risk evaluations undertaken for potato and spring wheat production, by means of the risk indicator model (EPRIP), indicated that the agreement, with MACRO_GV and field data, was best when simulations were accomplished with calibrated values. The modification of both parameters simultaneously gave a good consistency between EPRIP and MACRO_GV, in respect to metribuzin and MCPA. In contrast, the agreement for low dose pesticides (rimsulfuron and tribenuron-methyl) was not as good. Risk classification of MCPA and metribuzin were also reflected by findings in the field. Due to the lack of simulation results, it is difficult to give a clear answer as to whether output values of EPRIP are reliable and as to whether the model is suitable for Norwegian conditions or not. More simulations should be carried out in order to support the findings in this study and to give a more specific answer.

International audience; Bio-economic models can be used to assess the impact of policy and environmental measures through economic and environmental indicators. Focusing on agricultural systems, farmers’ decisions in terms of cropping systems and the associated crop management at field scale are essential in such studies. The objective of this paper is to present a study using a bio-economic model to assess the impact of the Nitrate Directive in the Midi-Pyrenees region (France) by analyzing, at the farm scale, farm income and three environmental indicators: nitrate leaching, erosion and water consumption. Two scenarios, the 2003 CAP reform (baseline scenario) and the Nitrate Directive (policy scenario), with a 2013 time horizon, were developed and compared for three representative arable farm types in the Midi-Pyrenees region. Different types of data characterizing the biophysical context in the region (soil, climate), the current cropping systems (rotation, crop management) and farm resources (irrigated land, labor) were collected to calibrate and run the models. Results showed that the implementation of the Nitrate Directive may not affect farm income. However, significant modifications to cropping systems and crop allocation to soil types were simulated. Contrary to expectations, nitrogen leaching at the farm scale did not change. Overall water consumption increased and soil erosion decreased due mainly to a modification in cropping patterns and management by soil type. This study provides an example of unanticipated effects of policy and trade-offs between environmental issues.

Irrigated agriculture is one of the most important sources of nitrate pollution of water resources. For this reason, during the past decade, various policies have been proposed in order to prevent this negative impact of farming activities. The aim of this work is therefore to analyze the effects of the joint application of the last Common Agriculture Policy (CAP) reform with different policy instruments designed to mitigate nitrate pollution. To this end, models based on Positive Mathematical Programming have been developed to enable simulating irrigators' productive behaviour in the event of the implementation of these instruments. The results indicate that the latest CAP reform (partial decoupling of subsidies) will by itself lead to an important reduction in nitrate pollution. If this reduction is not regarded as being sufficient, other specific policy instruments could further reduce this source of pollution. In this sense, the most suitable one could be the application of nitrogen fertilization quotas., La agricultura de regadío es una de las principales fuentes de contaminación por nitratos de los recursos hídricos. Por este motivo en los últimos años han surgido diferentes políticas encaminadas a evitar esta externalidad negativa de la actividad agraria. En este sentido, el objetivo de este trabajo es analizar los efectos de la aplicación conjunta de la última reforma de la Política Agraria Común (PAC) y diferentes instrumentos políticos mitigadores de la contaminación por nitratos. Para ello se han empleado modelos de simulación basados en la programación matemática positiva, los cuales permiten simular el comportamiento productivo de los regantes frente a la hipotética implementación de tales instrumentos. Los resultados obtenidos ponen de manifiesto que esta externalidad negativa va a reducirse de forma significativa gracias a la última reforma de la PAC (desacoplamiento parcial de las ayudas). Si esta reducción no se considerase suficiente, otros instrumentos específicos permitirían una reducción adicional de esta fuente de contaminación. En este sentido el instrumento que puede resultar más adecuado es el establecimiento de límites máximos a la fertilización nitrogenada.

The sources of mercury (Hg) variability in agricultural soils have been evaluated using 624 soil samples that were taken in the northeast of Spain. The Hg concentration ranges were 1-717 microg/kg. This was a wide range, although 90% of the values for Hg contents were estimated between 2.5 and 70 microg/kg. Other soil parameters (the pH, organic matter, carbonates and particle size) showed little correlation with the Hg content. The anthropogenic influence was linked to specific practises, in particular the application of slurries. Maps of the spatial distribution indicated various areas with high concentration levels that are attributed to anthropogenic influences. Evidence of human activity can be seen in the Ebro delta, which reflects the accumulation of metals in the basin over many years, and on the Ebro headwaters, characterized by intense mining and smelting activities in the past. A significant portion of the increased Hg content in the Ebro valley probably comes from the deposition of anthropogenic atmospheric Hg due to emissions from industrial activities., En este trabajo se ha evaluado la variabilidad espacial en la concentración de mercurio (Hg) en suelos agrícolas utilizando 624 muestras recogidas en el noreste de España. Aunque se muestra un amplio rango en la concentración de Hg (1-717 microg/kg), el 90% de los valores varía entre 2,5 y 70 microg/kg. El contenido de Hg en suelos se ha visto ligeramente correlacionado con otros parámetros edáficos (pH, materia orgánica, carbonatos y textura). La influencia antropogenia en la concentración de Hg en suelos se ha visto ligada a prácticas agrícolas específicas, en particular la aplicación de purines. El mapa de la distribución espacial muestra varias áreas con niveles de Hg más elevados que pueden ser atribuidos a influencias humanas. El delta del Ebro es una de las áreas que refleja los efectos de la actividad humana como consecuencia de la acumulación de metales en la cuenca durante años, así como la cabecera del valle, caracterizada por una intensa actividad minera en el pasado. Otra fuente importante que probablemente incremente el contenido en Hg en suelos del valle del Ebro es la procedente de la deposición atmosférica, debida a las emisiones de las actividades industriales.

The sources of mercury (Hg) variability in agricultural soils have been evaluated using 624 soil samples that were taken in the northeast of Spain. The Hg concentration ranges were 1-717 microg/kg. This was a wide range, although 90% of the values for Hg contents were estimated between 2.5 and 70 microg/kg. Other soil parameters (the pH, organic matter, carbonates and particle size) showed little correlation with the Hg content. The anthropogenic influence was linked to specific practises, in particular the application of slurries. Maps of the spatial distribution indicated various areas with high concentration levels that are attributed to anthropogenic influences. Evidence of human activity can be seen in the Ebro delta, which reflects the accumulation of metals in the basin over many years, and on the Ebro headwaters, characterized by intense mining and smelting activities in the past. A significant portion of the increased Hg content in the Ebro valley probably comes from the deposition of anthropogenic atmospheric Hg due to emissions from industrial activities. En este trabajo se ha evaluado la variabilidad espacial en la concentración de mercurio (Hg) en suelos agrícolas utilizando 624 muestras recogidas en el noreste de España. Aunque se muestra un amplio rango en la concentración de Hg (1-717 microg/kg), el 90% de los valores varía entre 2,5 y 70 microg/kg. El contenido de Hg en suelos se ha visto ligeramente correlacionado con otros parámetros edáficos (pH, materia orgánica, carbonatos y textura). La influencia antropogenia en la concentración de Hg en suelos se ha visto ligada a prácticas agrícolas específicas, en particular la aplicación de purines. El mapa de la distribución espacial muestra varias áreas con niveles de Hg más elevados que pueden ser atribuidos a influencias humanas. El delta del Ebro es una de las áreas que refleja los efectos de la actividad humana como consecuencia de la acumulación de metales en la cuenca durante años, así como la cabecera del valle, caracterizada por una intensa actividad minera en el pasado. Otra fuente importante que probablemente incremente el contenido en Hg en suelos del valle del Ebro es la procedente de la deposición atmosférica, debida a las emisiones de las actividades industriales.

Irrigated agriculture is one of the most important sources of nitrate pollution of water resources. For this reason, during the past decade, various policies have been proposed in order to prevent this negative impact of farming activities. The aim of this work is therefore to analyze the effects of the joint application of the last Common Agriculture Policy (CAP) reform with different policy instruments designed to mitigate nitrate pollution. To this end, models based on Positive Mathematical Programming have been developed to enable simulating irrigators' productive behaviour in the event of the implementation of these instruments. The results indicate that the latest CAP reform (partial decoupling of subsidies) will by itself lead to an important reduction in nitrate pollution. If this reduction is not regarded as being sufficient, other specific policy instruments could further reduce this source of pollution. In this sense, the most suitable one could be the application of nitrogen fertilization quotas. La agricultura de regadío es una de las principales fuentes de contaminación por nitratos de los recursos hídricos. Por este motivo en los últimos años han surgido diferentes políticas encaminadas a evitar esta externalidad negativa de la actividad agraria. En este sentido, el objetivo de este trabajo es analizar los efectos de la aplicación conjunta de la última reforma de la Política Agraria Común (PAC) y diferentes instrumentos políticos mitigadores de la contaminación por nitratos. Para ello se han empleado modelos de simulación basados en la programación matemática positiva, los cuales permiten simular el comportamiento productivo de los regantes frente a la hipotética implementación de tales instrumentos. Los resultados obtenidos ponen de manifiesto que esta externalidad negativa va a reducirse de forma significativa gracias a la última reforma de la PAC (desacoplamiento parcial de las ayudas). Si esta reducción no se considerase suficiente, otros instrumentos específicos permitirían una reducción adicional de esta fuente de contaminación. En este sentido el instrumento que puede resultar más adecuado es el establecimiento de límites máximos a la fertilización nitrogenada.

Communication orale; International audience