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Developing Mid-Tier Supply Chains (France) and Values-Based Food Supply Chains (USA) : A Comparison of Motivations, Achievements, Barriers and Limitations
No full textInternational audienceMid-tier supply chains/values-based food supply chains have emerged, in both France and the United States, as viable alternatives for small and mid-sized farms that had previously struggled. These supply chains deliver more products to a larger region than short supply chains such as farm-direct markets and are distinguished from the dominant long supply chains by (1) products that are differentiated from the mainstream based on superior quality, environmental stewardship and social responsibility; and (2) the characteristics of the strategic relationships that link the supply chain participants. On the demand side, regional supermarkets, restaurants, public and private institutional buyers, and individual consumers have demonstrated their eagerness to seek out and pay premiums for these types of high-quality food products that are delivered via trusted and transparent supply chains and characterized by their authentic farming stories. The set of case studies presented in this paper (three from each country) will highlight both the parallels and differences in the development of these innovative supply chains between two countries with quite dissimilar agricultural and food sector traditions and policies
Fabrique et représentations du paysage : le regard initié des agriculteurs. Des territoires rhône-alpins au bocage charolais
No full textNational audienc
Le projet AgrInnov : développer des indicateurs de qualité biologique des sols
No full textEA BIOmEEABIOmELe projet AgrInnov : développer des indicateurs de qualité biologique des sols. Congrès annuel de la Société Suisse de Pédologi
Early assessment of ecological services provided by forage legumes in relay intercropping
No full textIn organic agriculture, weeds and nitrogen deficiency are the main factors that limit crop production. The use of relay-intercropped forage legumes may be a way of providing ecological services such as weed control, increasing N availability in the cropping system thanks to N fixation, reducing N leaching and supplying nitrogen to the following crop. However, these ecological services can vary considerably depending on the growing conditions. The aim of this study was to identify early indicators to assess these two ecological services, thereby giving farmers time to adjust the management of both the cover crop and of the following crop. Nine field experiments were conducted over a period of three years. In each experiment, winter wheat was grown as sole crop or intercropped with one of two species of forage legumes; Trifolium repens L. or Trifolium pratense L Two levels of fertilization were also tested (0 and 100 kg N ha(-1)). After the intercropping stage, the cover crop was maintained until the end of winter and then destroyed by plowing before maize was sown. Legume and weed biomass, nitrogen content and accumulation were monitored from legume sowing to cover destruction. Our results showed that a minimum threshold of about 2 t ha(-1) biomass in the aboveground parts of the cover crop was needed to decrease weed infestation by 90% in early September and to ensure weed control up to December. The increase in nitrogen in the following maize crop was also correlated with the legume biomass in early September. The gain in nitrogen in maize (the following crop) was correlated with legume biomass in early September, with a minimum gain of 60 kg N ha(-1) as soon as legume biomass reached more than 2 t ha(-1). Legume biomass in early September thus appears to be a good indicator to predict weed control in December as well as the nitrogen released to the following crop. The indicator can be used by farmers as a management tool for both the cover crop and following cash crop. Early estimation of available nitrogen after the destruction of the forage legume can be used to adjust the supply of nitrogen fertilizer to the following crop
Protecting water from agricultural diffuse pollutions: between action territories and hydrogeological demarcation
No full textThe contamination of water resources by non-point pollution of agricultural origin, primarily nitrates and pesticides, has become a major issue in water policies. In France, the national consultation of the Grenelle of the Environment in 2007 led to project approaches, aimed at protecting Water Catchment Areas (WCA). Based on the implementation of preventive management, WCA projects aim at negotiating changes in farming practices in these zones, including conversion to organic farming. But difficulties occur in creating links between WCA and organic farming in these projects. Beyond the conflicts between different stakeholders often put forward, we suggest adopting a geographical approach on the interactions between WCA and the action territories of three types of stakeholders. A combination of statistical, GISprocessing and comprehensive methods was used to study the cross-referencing between WCA, defined according to hydrogeological bases, and action territories of farmers, collection companies and local a thorities. The results show how the demarcation of the water catchment areas on biophysical bases struggles to be effective for action, in particular for the agricultural question and the development of organic farming. In taking account of organisational levels and spatial patterns, the article illustrates the discrepancy between WCA and action territories of farmers, collectors and local authorities. These results call for better integration of the concept of territory project in WCA projects, allowing interests to be combined and reflection to be directed towards local governance in the field of water quality
La nature en ville et le cas spécifique des jardins urbains : approche géographique et historique de la ville de Lyon et de son agglomération
No full textThis PhD thesis deals with the evolution of the notion of collective garden and their place and functions in the city. Firstly, on the basis of an historical and geographical perspective, it provides a background of the notion of garden in the Mediterranean area, between East and West, from the ancient world to the modern day. The concept of garden has taken over time very different meanings, food-producing garden or pleasure garden, but also private gardens, public and community gardens.Then our approach focuses on collective gardens, namely workers' gardens, family gardens and community gardens. Our research focuses on the city of Lyon and its metropolitan area from the late 19th century to today. This historical and geographical analysis is based on both an archival work and a cartographic approach. To mix historical depth and spatial approach we inquire about the historical, political, demographic, economic and social factors that determine the location and the uses of collective gardens. This analysis of the spatial dynamics throughout the twentieth century reflects the evolution of their place and their functions in the city. This allows us to identify the values and functions of collective gardens that have a high stability over time, while others refer to conceptions and concerns which are historically and geographically situated. We thus pay particular attention to place the issue of community gardens in transformations of urban policies, characterized for the recent period by the increasing influence of sustainable development concerns and emerging issues on the place of nature in cities.Cette thèse est consacrée à l’évolution de la notion de jardin collectif et de leur place dans la ville. Elle s’appuie tout d’abord sur une mise en perspective historico-géographique de la notion de jardin dans le bassin méditerranéen, entre orient et occident, de l’antiquité à nos jours. La notion de jardin a pris, en effet, au cours du temps des acceptions très différentes, jardins nourriciers ou jardins d’agréments, mais aussi jardins privés, jardins publics et jardins collectifs. Nous resserrons ensuite notre approche sur les jardins collectifs, jardins ouvriers, jardins familiaux et aujourd’hui jardins partagés. Pour cela nous focalisons notre recherche sur l’agglomération lyonnaise de la fin du 19ème siècle à nos jours. Cette analyse historico-géographique s’appuie à la fois sur un travail d’archives et sur une cartographie des jardins. Pour associer, profondeur historique et approche spatiale, nous interrogeons les facteurs historiques, politiques, démographiques, économiques et sociaux qui, durant cette période, se révèlent déterminants dans la localisation et les usages des jardins collectifs. Cette analyse des dynamiques spatiales de création de jardins tout au long du 20ème siècle, reflète l’évolution de leur place et de leurs fonctions dans la ville. Ceci nous permet de révéler à la fois des valeurs et des fonctions attribuées aux jardins qui ont une forte stabilité dans le temps, alors que d’autres renvoient à des conceptions et à des préoccupations historiquement comme géographiquement situées. Pour cela, nous attachons une attention particulière à resituer la question des jardins collectifs dans les transformations des politiques urbaines, avec pour la période récente la montée en puissance des préoccupations liées au développement durable et à la place de la nature en ville
Diversité des cheminements en agriculture biologique : le sens du métier en question ?
No full text[Departement_IRSTEA]Territoires [TR1_IRSTEA]DTAM [Axe_IRSTEA]DTAM1-REPROCe numéro comprend les articles correspondant aux présentations du Colloque Dynamiques de développement des productions agricoles et alimentaires biologiques, qui s’est tenu à Rennes le 28 avril 2016.International audienceFarmers turning to organic have to face many challenges. One of the most ignored, paradoxically, is thereconstruction of professional patterns that such a decision entails. We will intend here to show howgoing organic and making his way along significantly lead to the change as well as to the restoration ofvalues. We selected three typical cases within a large sample of respondents, as they reveal significantfeatures to be considered. According to the stages or circumstances, it might be the expertise acquired,or self-reliance, or a new way to find an easy-to-access market, and so on. All these components matchto set things in motion and prompt change of attitudes and representations. How stands the farmer andwhat means organic farming to him, are not fixed for ever neither set in stone, before certification orafterwards as well. Our survey shows an astonishing, noticeable variety of career paths and ways oftaking them. It highlights the need to better understand what makes sense for a farmer when seeking fora new position and experimenting new practices and to which extent it is operative, especially if weconsider the increasing strain on such an activity nowadays.Les agriculteurs qui se convertissent à l'AB doivent relever de nombreux défis parmi lesquels la redéfinition du sens de leur métier, dimension jusque-là paradoxalement peu analysée. Dans cet article, nous proposons d'étudier en quoi la conversion et le cheminement dans l'AB s'accompagnent de recomposition du sens du métier. La présentation détaillée de trois cas permet de mettre en évidence des dimensions importantes de la recomposition du sens du métier. Selon les temporalités, l'agriculteur biologique valorise les savoir-faire techniques liés au rapport au vivant, l'autonomie retrouvée ou bien de nouvelles formes d'inscription de l'activité dans les marchés. L'une de ces dimensions peut entraîner l'autre, il s'ensuit des changements de sens du métier. Le positionnement de l'exploitant vis-à-vis de l'AB et le sens donné au métier ne sont pas prédéterminés au moment de la certification, ni figés dans le temps. L'approche révèle une diversité étonnante de cheminements dans l'agriculture biologique et l'utilité d'étudier le besoin de redéfinition du métier, compte-tenu de l'importance desbouleversements qui l'affectent et de sa fragilisation
Horizontal distribution of the cell abundance and toxicity of Microcystis in a hypereutrophic Moroccan reservoir
No full textInternational audienc
Traitement des données manquantes dans un projet participatif sur la biodiversité des sols agricoles
No full textInternational audience-En prenant en compte le pourcentage de DM par variables, la méthode d'imputation multiple par « Predictive Mean Matching » minimise le NRMSE et le critère de la moyenne des écarts à la matrice de corrélation. Cette méthode reconstitue mieux les données et déforme moins les relations linéaires entre les variables.-Cependant, la méthode d'imputation multiple par PMM est sensible à la proportion totale de DM. La méthode par le plus proche voisin semble nettement plus intéressante lorsque la proportion totale de DM augmente ou lorsque les DM sont de type MCAR (Missing Completely at Random).-Dans le projet AgrInnov, l'hypothèse de DM de type MAR (Missing At Random) semble la plus probable. Afin de diminuer la proportion totale de DM, une analyse par parcelles permettrait de définir une typologie des agriculteurs et d'adapter la stratégie d'échantillonnage des bio-indicateurs et des indicateurs agronomiques