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Les CIMS pour améliorer la productivité en Agriculture Biologique dans les systèmes de culture assolés
No full textCe numéro est constitué d’articles issus du colloque CIMS : Des Cultures Intermédiaires Multi-Services pour une production agroécologique performante, organisé le 4 octobre 2017 à Auzeville.National audienceMulti-service cover crops (CIMS) can provide numerous ecosystem services and play thus a crucial role in organic farming. The capacity of the CIMS to supply nutrients to the subsequent crop is of particular interest in organic farming due to the low fertiliser availability. CIMS aims also at maintaining soil organic matter content by counterbalancing crop exportations. They are an efficient mean to suppress pests in particular weeds through direct competition for resources or by the modification of the growing conditions. Other pest and disease control results mainly from the creation of favourable conditions for the conservation and the development of beneficial organisms.In some conditions, a direct control is also possible. Finally, the CIMS are an important element in the promotion of biodiversity. The expected services vary highly according to the farm typology. While field crop farms without livestock are looking for maintaining soil organic matter content and maximizing N supply by the CIMS, the main objective of vegetable growers is to control pests and diseases. The choice of the CIMS, as sole crop or in mixtures, and its management depends highly on the expected services. A tendency to replace the CIMS by temporary meadows or other forms of permanent cover is observed in arable crop farms.Les cultures intermédiaires multi services, ou CIMS, jouent un rôle essentiel en agriculture biologique (AB) du fait des nombreux services écosystémiques qu’elles peuvent rendre. La capacité des CIMS à apporter des nutriments à la culture suivante est particulièrement intéressante en AB en raison de la faible disponibilité en engrais.Les CIMS visent également de maintenir la teneur en matière organique des sols essentielle à leur fertilité en compensant les exportations des récoltes. Elles représentent aussi un moyen de lutte efficace contre les bioagresseurs, en particulier les adventices, par une compétition directe pour les ressources ou par des modifications du milieu de croissance. Le contrôle des maladies et ravageurs par les CIMS se fait principalement par la création de conditions favorables au maintien et au développement d’organismes bénéfiques. Dans certaines conditions, une régulation directe est également possible. Enfin, les CIMS sont un facteur important de promotion de la biodiversité. Les services recherchés varient fortement selon la typologie de l’exploitation. Alors que les exploitations de grandes cultures sans élevage chercheront à maintenir la teneur en matière organique et à maximiser l’apport d’azote par les CIMS, l’objectif prioritaire des exploitations maraîchères sera de contrôler la pression des maladies et des ravageurs. Le choix de la CIMS, espèce seule ou mélange de plusieurs espèces, ainsi que sa conduite seront déterminés en fonction des objectifs principaux recherchés. Une tendance à remplacer les CIMS par des prairies temporaires ou à les faire évoluer vers toute forme de couverture permanente est relevée sur les exploitations de grandes cultures
Enhancing planned and associated biodiversity in French farming systems
No full textInternational audienceAbstractIn a context of global change involving uncertainty in agricultural production, agroecological systems need to reduce their dependency on inputs and increase their resilience. Biodiversity-based techniques are promising, as they provide production services based on biological processes. Tracking farmer practices is an original approach aiming at identifying and analysing alternative systems and supporting the development of these techniques. We studied, for the first time, the on-farm implementation of six biodiversity-based techniques: (i) agroecological infrastructures, (ii) cropped varietal mixtures, (iii) agroforestry, (iv) intercropping, (v) cover cropping and (vi) crop rotation diversification. We first analysed the combinations of these techniques in a large sample of 194 French farmers. A multiple correspondence analysis followed by a hierarchical cluster analysis on principal components resulted in groups of farms with different combinations of these techniques. Then, deeper interviews were conducted with 29 farmers across three regions to analyse the various methods of applying the techniques in the context of their farm and to identify the conditions for their successful implementation. Taking advantage of this large and rare sample of almost 200 interviewed farmers, we identified six different groups of farms. From farms applying mainly cover cropping to comply with European regulations to much diversified farms implying the redesign of the farming system, we support the idea that different strategies of implementation of such biodiversity-based techniques co-exist. The in-depth interviews demonstrated that the level of diversification is related to farm characteristics and four factors mainly favoured the development of such techniques on farms: (1) available labour force and (2) specialised machinery (internal factors) as well as (3) access to market opportunities and (4) the exchange of knowledge through networking (external factors). Surprisingly, the conservation agriculture farmers of our sample did not apply significantly more biodiversity-based techniques. However, our results indicated that organic farmers applied significantly more of these techniques. Our results suggest that enhancing knowledge exchange through networks would favour the broader application of such techniques. It could also be relevant to gather farmers, industries and public authorities to favour the emergence of market opportunities
Apport de l’économie comportementale pour réduire l’usage des pesticides des agriculteurs : bilan du projet Coud’Pouce
No full textCe numéro comprend les articles issus du colloque de restitution Ecophyto Recherche « Des outils et des dispositifs pour éclairer les décisions, explorer les possibles et accompagner la transition vers des systèmes économes et multi-performants », qui s’est tenu à Saint-Malo, du 22 au 24 mars 2017.Economie comportementale, Economie expérimentale, Design de contrats agroenvironnementaux,Normes sociales, Evaluation de politiques publiquesBased on a quantitative and qualitative evaluation of the French agri-environmental schemes (AES) ofthe 2007-2013 period, the project Coud’Pouce investigates how behavioral biases can be mobilised toreinforce the impact of incentive schemes. The project results confirm that there are promising newways to improve agri-environmental policies that could be further tested at a larger scale: theintroduction of a collective component in agri-environmental payments, the use of agri-environmentalauctions; and the development of nudging campaigns based on social and personal norms. From amethodological standpoint, this project demonstrates that experimental and quasi-experimentalmethods are pertinent for the ex-ante and ex-post evaluation of public policiesLe projet Coud’Pouce (COmportement et Usage Des pesticides : POUr des Contrats Environnementauxinnovants) s’appuie sur un bilan qualitatif et quantitatif des mesures agro-environnementalesterritorialisées (MAET) de la PAC 2007-2013, pour analyser ensuite comment les biaiscomportementaux peuvent limiter ou renforcer la portée des interventions publiques destinées à inciterles agriculteurs à adopter des pratiques plus économes en pesticides. Les résultats montrent qu’il existedes pistes prometteuses d’amélioration des politiques agro-environnementales : l’introduction d’unecomposante collective dans les MAET, les appels à projet agro-environnementaux et l’utilisation d’unecommunication fondée sur les normes sociales ou personnelles. Ce projet met en avant l’intérêt de lamobilisation de méthodes expérimentales ou quasi-expérimentales pour l’évaluation ex-ante et ex-postdes politiques publiques
Consumers' willingness to pay for sustainable and innovative products: a choice experiment with upgradeable products
No full textInternational audienceUpgradeable products are designed to allow sequential improvements during their lifetime. Little is known about consumers' preferences for these eco-innovative products. We use a discrete choice experiment to assess the importance of several attributes of product upgrading on consumers' choices. Four types of products are investigated: a washing machine, a wireless (upright) vacuum, a traditional vacuum and a laptop computer. Our experimental design varies several attributes of upgradeability (the type of improvement, the time between initial purchase and first upgrade and the upgrade practical procedure). All other characteristics of products are kept constant except the purchase price and the upgrade fee. Individual values are elicited on the basis of the random utility model (RUM) and an estimated mixed logit model permits to compute willingness to pay indicators. The results indicate that consumers value positively the possibility to improve products' performance through upgrading, especially in terms of energy efficiency
A place based development of organic farming to tackle water pollution problems
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Amélioration de la méthode du profil cultural pour mieux décrire la structure dans les situations en non labour
No full textCT3 ; EnjS3 ; Département EA Conference: Workshop on Soil Structural Quality of Tropical Soils - Visual Evaluation Methods and Soil Compaction Prevention Strategies Location: Maringa, BRAZIL Date: MAY 26-29, 2014International audienceIn France, agronomists have studied the effects of cropping systems on soil structure using a field method that is based on a visual description of the soil structure. This "profil cultural" method was designed as a field diagnostic tool to identify the effects of tillage and compaction on soil structure dynamics. It is of great benefit to agronomists seeking to improve crop management and preserve soil structure and fertility. However, the "profil cultural" method was developed and has mainly been used in conventional tillage systems with regular ploughing. As there has been an increase in the use of various forms of reduced, minimum and no-tillage systems in many parts of the world, it is necessary to re-evaluate this method's ability to describe and interpret soil structure dynamics in no-till or reduced tillage. In these situations, changes in soil structure over time are mainly driven by compaction and by regeneration through natural agents (climatic conditions, root growth and macrofauna), therefore it is important to evaluate the effects of these natural processes on soil structure dynamics. These concerns have led to adaptations and amendments to the initial method based on field observations and experimental work in different cropping systems, soil types and climatic conditions. The description of crack types has been improved and a criterion of biological activity based on the visual examination of clods has been introduced. To test this modified method, a comparison with the initial method was undertaken and its ability to make diagnoses tested in five experiments in France, Brazil and Argentina. The adapted method allowed an improved assessment of the impact of cropping systems on soil functioning when natural processes were integrated into the description
