Deux épées à sphères du Centre-Ouest de la France

Two spheres hilted swords from Central-Western France. Iron nodule hilted swords are a particular sort of weapons of the end of the Second Iron Age. This paper is the technical and structural study of two old discoveries of Central-Western France ; the first found in the Charente river in Juac (Saint-Simon, Charente), the second from Germond (Deux-Sèvres). Numerous questions have not been resolved about the find of this one. These two swords are good examples of the two typological groups actually defined for this sort of weapons. Their study gives knew knowledges about these types : the second type appears to be very various for its realization. The european part of the study wants to singularise western discoveries, that were not yet well known, and gives evidences of the numerous craftsmen and workshops who produced this type of weapons.Les épées à sphères constituent une catégorie tout à fait particulière de l’armement à la fin du Second Age du Fer. Cette étude porte sur deux exemplaires anciennement découverts en Centre-Ouest ; le premier, trouvé dans la Charente à Juac, commune de Saint-Simon, fut dragué au siècle dernier alors que le second ne fut découvert qu’au début de ce siècle à Germond, dans des conditions entourées de nombreuses incertitudes : ces conditions nous ont conduit à privilégier l’aspect technique et structural de l’étude. Ces deux épées sont représentatives des deux grands groupes typologiques actuellement définis : leur étude a permis d’enrichir nos connaissances en ce domaine et d’en renouveler l’approche. L’épée de Juac constitue à ce jour l’unique spécimen local du premier groupe. Celle de Germond a pour sa part contribué à mettre en évidence la grande diversité qui caractérise les armes du second groupe, mieux représenté dans l’ouest de la France. Cette étude, dont l’objet est de singulariser un mobilier de la frange occidentale du monde celtique encore trop peu connu, souligne la grande diversité qui caractérisait ce type de production et suggère une multiplicité de maîtres d’œuvre et de pôles créateurs.Gendron Christian, Gomez de Soto José, Lejars Thierry, Pautreau Jean-Pierre, Uran Laurent. Deux épées à sphères du Centre-Ouest de la France. In: Aquitania : une revue inter-régionale d'archéologie, tome 4, 1986. pp. 39-54

Impact des restrictions d'eau sur les filières agro-alimentaires Nappe de la Beauce

L'étude sur l'" Impact des restrictions d'eau sur les filières agro-alimentaires de la Nappe de la Beauce " fait l'objet de conventions qui lient l'AFEID (Association Française pour l'Irrigation et le Drainage), le Cemagref, le Cirad, le bureau d'études Diataé et les Chambres d'Agriculture d'Eure-et-Loir et du Loiret avec le soutien du Ministère de l'Agriculture de l'Alimentation de la Pêche de la Ruralité et de l'Aménagement du Territoire. Le présent document constitue un rapport d'analyse de travaux accomplis et d'enquêtes réalisées sur une zone ciblée de la Nappe de la Beauce, au cours de l'année 2011. (Résumé d'auteur

L’archéologie méditerranéenne et proche-orientale dans l’ouest de la France

Textes réunis par Dominique Frère

Vers des recherches dé-coïncidentes dans un contexte de fragilité des écosystèmes et des systèmes agroalimentaires

International audienc

Vers des recherches dé-coïncidentes dans un contexte de fragilité des écosystèmes et des systèmes agroalimentaires

International audienc

Une recherche dé-coïncidente pour se préparer aux crises environnementales et alimentaires

International audienceThe great fragility of ecosystems supporting food production requires alternative ways of thinking regarding the scientific research, as well as a bold analysis of public policies to be implemented to feed the planet, in an environment that would become hostile to agricultural production. In order to preserve the food ecosystems essential to human development, this book presents anticipatory visions and prospective analyzes based on the concept of “de-coincidence”, developed by the philosopher François Jullien. This search for a creative sense, freed from the coincidences of common sense, from the “déjà vu”, invites us to rethink the methods of organizing research in agronomy or in the field of the environment in order to encourage initiatives that go off the beaten track. Implementing new forms of research organization is necessary. It is also important to consider “worst” scenarios, in particular by imagining extreme configurations for the future, in which food production would become impossible in a “natural” environment. In order to define innovative solutions and effective public policies, this work offers three “de-coincident” essays aimed at designing pathways that would make it possible to prepare for the transformations to come. The first essay discusses institutional solutions for promoting de-coincident research. The next one focuses on a fictitious “worst-case” scenario in a context of extreme global warming. Eventually, the last essay analyzes what we can do “right now” to brace for “the worst” and prevent certain crises from occurring.La très grande fragilité des écosystèmes supportant la production alimentaire nécessite une réflexion alternative sur les orientations de la recherche scientifique, ainsi qu’une analyse audacieuse des politiques publiques à mettre en œuvre pour nourrir la planète, dans un environnement qui deviendrait hostile à la production agricole. Afin de préserver les écosystèmes alimentaires indispensables au développement humain, ce livre présente des visions anticipatrices et des analyses prospectives relevant du concept de dé-coïncidence, développé par le philosophe François Jullien. Cette recherche d’un sens créatif affranchi des coïncidences du sens commun, du « déjà-vu », invite à repenser les modes d’organisation de la recherche en agronomie ou dans le domaine de l’environnement afin de favoriser des initiatives sortant des sentiers battus. Mettre en place de nouvelles formes de structuration de la recherche est nécessaire, de même qu’envisager le pire, notamment en imaginant de manière frontale des configurations extrêmes, dans lesquelles la production alimentaire deviendrait impossible en milieu « naturel ». Afin de définir des solutions innovantes et des politiques publiques efficaces, cet ouvrage propose trois essais dé-coïncidents visant à concevoir des cheminements qui permettraient de se préparer aux transformations à venir. Le premier essai évoque des pistes institutionnelles pour favoriser une recherche dé-coïncidente. Le suivant se focalise sur un scénario fictif « du pire » dans un contexte très dégradé par le réchauffement climatique. Enfin, le dernier essai analyse ce que nous pouvons faire « dès à présent » pour se préparer « au pire » et empêcher certaines crises d’advenir

An interdisciplinary approach to increase wheat within-field diversity and promote agro-ecosystem services

International audienceOne major challenge for increasing agriculture sustainability is to better mobilize crop genetic diversity, as prone by agroecology. A simple way to increase within-field diversity is to use cultivar mixtures, and this has been successfully applied to a few crops in the past. Despite numerous scientific papers documeting the value of cultivar mixtures in wheat and other cereals, especially to control diseases, their cultivation has remained marginal throughout the world. To understand the origin of this gap between scientific knowledge and agricultural practices, the French project Wheatamix explored the synergies mobilized by cultivar mixtures, their impact on various ecosystem services, and their potential to reinforce the sustainability, resilience, and multi-functionality of agriculture. It focused on the agro-ecological and socio-economic impacts of variety associations at different scales, from the plant level up to the wheat supply chain. The project aims at developing new blending and breeding methods to design performing mixtures.To understand how plant-to-plant interactions shape wheat mixtures performances, Wheatamix has set five objectives: 1) describe the variability of morphological and ecological traits in a panel of 57 varieties; 2) explore variability by blending 16 contrasted varieties from the panel into 72 mixtures, composed of 2, 4, and 8 components; 3) study the ecosystem services provided; 4) assess the technical and economic performances in farmer conditions; 5) evaluate the impact of cultivar mixtures on the wheat supply chain. To achieve these goals, this project has developed an interdisciplinary approach, mobilizing agronomy, ecology, economics, ecophysiology, epidemiology, genetics, and management sciences. The project brought together scientists from 10 labs, as well as agricultural advisers and farmers from 6 French counties. The project first described the functional diversity of 57 varieties, highlighting the effects of modern breeding on trait variability, that lowered variability of traits subject to direct selection, and impacted both plant architecture, physiological traits as nutrient absorption, but also trade-off between traits. Wheatamix then surveyed how variation in mixture diversity impacted wild communities. A first result highlighted the low abundance of macro-organisms in this experiment: no relationship was found between the number of varieties in a mixture and the diversity/abundance of earthworms, weeds, mycorrhizae, springtails, beetles, nematodes. However, a significant effect of mixture diversity on the abundance of some spiders, and on nitrifying bacteria, was observed. Coming to ecosystem services, disease regulation (rust and septoria) has been confirmed as the most strongly and positively affected by varietal associations, raising also the strong effects of architectural variability of the canopy (septoria). Diversity also contributed to higher predation rates on aphids. Lastly, soil nitrification and denitrification activities were significantly affected by mixture diversity on 4 surveyed sites, contributing to a shift in plant nutrition and positive effect of greenhouse gas emission.Co-design of variety mixtures was carried out with farmers, technical advisers, and scientists. For three years, 30 farmers in the Paris basin proposed varietal blends and measured their performance on their farms. This exchange first highlighted that the first goals for farmers was to i) secure their production ii) simplify plot management. Then co-design workshops allowed to propose assembly rules and design mixtures, resulting in a wide diversity of sown mixtures. Field trials revealed that in more than 70% of the cases, the mixture had a higher yield than the mean of its components. This work highlighted farmers needs and resulted in a Multicriteria Evaluation Tool, helping farmers and advisers to design mixtures. The survey of the wheat supply chain finally highlighted the need for a concerted innovation among the various actors. Finally, Wheatamix also developed new statistical method to infer mixing ability, allowing both to blend the best mixers, and also to propose new breeding methods.Coupling various disciplines and approaches, such as ecophysiological modeling of plant competition (FSPM WALTer), field and controlled experiments, theoretical framework in ecology (sampling vs complementarity effects, functional traits and tradeoff), and mixture co-design and surveys with stakeholders, Wheatamix has allowed to understand the interest of cultivar mixtures for farmers. Wheat cultivar mixtures are experiencing an exponential growth: they only represented 2% of bread wheat sown in 2010, and are presently at 8%, raking at the first position on the cultivar list. Wheatamix emphasizes the need for an interdisciplinary approach when addressing agroecological subjects, and illustrates the strong mutual benefices between agronomic and ecological sciences