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In Tune With the Times? When Neo‐Peasants Choose Animal Traction to be Part of a More Sustainable Production Model
No full textInternational audienceAs regards alternative agricultural practices today, it is worth noticing the increase in the use of animal traction (AT) in France. Yet, the reasons for this reappropriation remain unclear. The life paths and motivations of users are the focus of this article. The study is based on 33 qualitative interviews with French farmers. It uses Gasson's theoretical framework and a life course analysis. Findings show that farmers who have chosen AT first tend to question the agricultural model. They can be described as neo-rurals motivated by their political opinions, a desire for greater autonomy and their passion for horses. These neo-peasants have opted for animal-drawn cultivation because they reject the main agricultural system and wish to create a new connection with nature. This study is also addressed to policymakers and people advocating more sustainable agricultural practices in general.All authors have participated in (a) conception and design or analysis and interpretation of the data; (b) drafting the article or revising it critically for important intellectual content; and (c) approval of the final version.</p
Work in agriculture: A blind spot in reducing pesticide use on dairy farms?
No full textInternational audienceCONTEXT: Implementing alternative practices to the use of pesticides involves work issues that can limit adoption of these practices, particularly on dairy farms. Depending on how practices change, work organization may completely change, additional skills and knowledge may be required, and system complexity may increase, inducing a higher mental workload. This can result in an excessive total workload for already overburdened farmers.OBJECTIVE: The present study examines whether work limits the implementation of alternative practices to reduce pesticide use on dairy farms, depending on the amount of change the practices require. Three work dimensions were considered: work organization, skills and knowledge, and physical and mental workload.METHODS: We used nine semi-structured interviews with crop and livestock experts in Brittany (France’s leading region for dairy production) to classify multiple categories of practices by their degree of difficulty and the type of work dimension involved, with a specific focus on three practices: using resistant crop varieties, mechanical weed control and extending crop rotations.RESULTS AND CONCLUSIONS: First, experts emphasized certain alternative practices over others depending on the institution to which they belonged. Second, the need to balance the feeding system and an increase in herd size, which is not compatible with all alternative practices, were barriers specific to dairy farms. Third, all three practices we focused on were skill- and knowledge-intensive, but in different ways. Using resistant crop varieties requires access to the right information, while mechanical weed control raises issues of training, investment or outsourcing. Finally, extending crop rotations, considered as a redesign of the production system, requires obtaining the resources, time and autonomy to think about new rotations.SIGNIFICANCE: This study shows that, in addition to work organization, other work dimensions are crucial for reducing pesticide use on dairy farms
Litter C:N Ratio and Soil Water Retention Drive Early CO₂ and N₂O Fluxes from Recycled Litter on Urban Lawns
No full textInternational audienceUrban green spaces (UGSs) play a vital role in enhancing urban sustainability by providing ecosystem services. Lawns, which cover up to 50–70% of UGSs globally, vary in vegetation type and generate substantial litter from trees, shrubs, and herbaceous plants. Much of this litter is exported, although recycling it into soil could improve soil health while reducing indirect greenhouse gas emissions associated with litter blowing, transport, and composting. However, litter decomposition may also lead to direct emission of nitrous oxide (N₂O)—a powerful greenhouse gas.Litter biochemistry influence on N₂O fluxes during litter decomposition was studied on two soils from a low- and a high-intensity management lawn. The high-intensity management soil had higher organic C and N contents and greater water retention capacity. Five litter types, selected from twenty-eight representative UGS species, were chosen for their contrasting biochemistry (e.g., C:N ratio and lignin content). These litters were applied at the soil surface and incubated in the lab for 14 days (15°C, 100% field capacity). Carbon dioxide (CO₂) and N₂O emissions, along with mineral nitrogen dynamics, were measured. Cumulative CO₂ and N₂O emissions depend on litter C:N ratio and soil water retention capacity. Green litter with low C:N ratio (i.e., Lolium) produced higher emissions, while senescent litters with high C:N ratios (e.g., Fraxinus, Meadow grasses) induced microbial nitrogen immobilization thus limiting emissions. The high-intensity soil showed the highest cumulative N₂O emissions across all litter types (averaging 1.5 kg N ha-1) due to higher water retention capacity. N₂O emission factors (1.2–3.7%) exceeded the IPCC default for crop residues (0.6%). A power regression with C:N ratios from the twenty-eight collected litter types suggested average N₂O emission factors of 1.5% for senescent and 3.5% for green litters. These findings suggest for the first time that recycling litter on an intensively managed lawn soil can result in significant N₂O emissions, due to organically rich conditions promoting notably high water retention capacity. However, litter recycling on a soil with lower water retention capacity, typically the low-intensity management soil, may represent a sustainable practice with low N₂O emission potential, while also providing substantial benefits for soil fertility, water cycling, and biodiversity
Opinion note: Digitalization in sensory and consumer science – Summary perspectives from presentations at the 15th Pangborn sensory science symposium
No full textInternational audienceThe arrival of digitalization in sensory-consumer science (Meiselman et al., 2022) has the potential to expand business and research capabilities and make better use of team capacities (Lawlor et al., 2023). However, digital transformation is not so much of a revolution, paradigm shift, as more of an organic evolution of the technical capabilities used to explore and create value for both consumers (e.g., leading to superior user experiences etc.), and for organizations (e.g., increasing speed of innovations etc.). However, with no universally agreed definition of digitalization in place its true potential in terms of aim, scope and value to sensory and consumer science remains to be defined. That said, some authors have proposed first definitions such as “the use of technology to measure, explain and/or predict sensory perception” (Lawlor et al., 2023). Future definitions could target other aims (e.g.,more rapid innovation timelines, increased data driven decision making etc.), scopes or value, meaning that, at least at this early stage withmultiple objectives, one universally applicable definition may be challenging to achieve. So how ready are we for digitalization and Artificial Intelligence (AI) (Pineau, 2023)? At the 15th Pangborn Sensory Science Symposium several authors presented workshops, oral and poster talks on differentapplications of digitalization within the sensory and consumer science field. Important insights came from both the talks and the discussionsthat followed, insights that we believe can benefit the broader sensory community in starting on, or continuing with, the digital transformation of their organization and teams
Pasteurization treatments of whole and liquid egg products: optimizing safety and quality parameters
No full textInternational audienceEggs are consumed all over the world as table egg or egg products. The safety of eggs is thus a major concern for both egg industry and consumers, as they may be quite easily contaminated by both pathogenic and/or spoilage bacteria. Despite the natural arsenal of antimicrobial defenses of eggs, the safety of eggs and egg products is nowadays mainly guaranteed by pasteurization treatments. After reminding the principle of pasteurization, the current technologies used for shell eggs, liquid egg products and egg white powders are presented. Their consequences on egg product functionalities and nutritional quality are considered to drive the optimization of the processes toward safe, functional and healthy egg products. The growing issues of the sustainability and environmental impact of the processes are also questioned as the current challenge of egg industry
CHAPTER EIGHT : Agricultural human-water systems
No full textInternational audience*Ding!* Allison checks her phone—it’s a notification that there’s an issue with her groundwater system, reporting lower-than-expected pressure due to a malfunctioning valve. Driving to the town for a replacement part, she passes by the rusted skeletons of her former neighbors’ center pivot systems. After decades of overuse, the aquifer in her part of the High Plains regions of the United States, can no longer sustain large-scale irrigated agriculture. When the groundwater dried up, so did the local economy—the closest equipment supplier is two counties over, since all the businesses in her hometown shuttered when farms started being bought up by out-of-state, corporate owners. The absentee landlords were not invested for the long-term—they just used the water until it was gone, producing high-water-use crops to sell overseas, then reallocated their port- folio elsewhere. Instead of selling, Allison took a risk and invested in high-efficiency precision irrigation systems while overhauling her soil health management to retain what little rainfall does fall on her land. A few other neighbors are still here, eking out a living on dryland crops and worrying about the whims of the weather. But most have retired and sold their farms since their kids (and grandkids) have moved to the city for better jobs. Allison has been slowly expanding her operations into this fallowed land, but even with her high-tech equipment, she’s reaching her operational limits since the population has crashed and she cannot find enough help. She believes that if others follow the approach she is using, irrigation could be sustainable on a limited basis, better jobs. has been slowly expanding her operations into this fallowed land, but even with her high-tech equipment, she’s reaching her operational limits since the population has crashed and she cannot find enough help. She believes that if others follow the approach she is using, irrigation could be sustainable on a limited basis, 322 Pedro Medeiros, et al. allowing the local economy to bounce back—but will enough people follow her lead, orwill farming go the way of the aquifer and disappear? What Allison is experiencing here is in common with the experience, to varying degrees, of millions of farmers around the world, manifesting differently in different places. Demand for food to meet the needs of a growing human population and changing lifestyles under a changing climate is leading to overexploitation of freshwater resources (rivers, aquifers, lakes) and deterioration of the aquatic environment. This is putting farmer livelihoods at risk and has been leading to, in many places, abandonment of farming, collapse of the rural economy, migration to cities, pressure on water infra- structure in cities. This situation compounds the growing global water crisis. This chapter is devoted to issues such as these that arise in the context of agricultural human- water systems
Solid‐phase organization and shrinkage properties of some growing media constituents according to particle size
No full textInternational audienceParticle size is a key factor in shaping water and air retention properties and drainage capacity of growing media. Thus, manufactured growing media are made of screened, crushed, or sieved raw materials whose particle sizes are adapted to cropping objectives. The relationships between the particle size distribution of the growing media constituents and the resulting structure are, however, not well known, which requires better understanding of particle arrangement and its change with water upon shrinkage. A proper characterization of the structure would help to guide substrate manufacturing, which is inherently complex due to the use of various materials made up of heterogeneous particles in terms of size and shape. To this aim, we analyzed the shrinkage of white and black peats, coir, pine bark and wood fiber, raw material, and derived particle size fractions extracted by sieving. Hyprop systems coupled to linear vertical displacement transducers were used to determine the shrinkage curves. The dual porosity shrinkage XP model (XP model) was used to analyze the hydrostructural behavior of the different growing media constituents. The possible distinction of interparticle and intraparticle pores, based on the dual pore system assumption of the shrinkage model, was discussed. Interparticle porosity volume represented the major part of the total porosity, whatever the materials and particle size fractions. Greater volume shrinkage of interparticle porosity was observed for the smaller particle size fractions of materials. Conversely, intraparticle porosity volume shrinkage is of the same magnitude for all particle size fractions. The use of the XP model to study growing media is relevant, although no residual domain on the shrinkage curves was observed. This work revealed that particle arrangement and physical behaviors during drying of materials depend on the nature of constituents but also highly on particle size fraction. These results provide a complementary approach for characterizing the pore functional properties of growing media
Des forêts classées aux paysages du patrimoine mondial. L’héritage forestier colonial dans la patrimonialisation contemporaine des paysages de savane en Afrique de l’Ouest
No full textInternational audienceThis article analyses how protected areas in West Africa originated and evolved, and more specifically those in savanna environments. It takes a cross-disciplinary approach combining scientific literature, historical sources, cartographic data and field surveys conducted between 2023 and 2024 in the Kédougou region of Senegal. The study highlights the colonial origins of early environmental protection policies which were centred on a utilitarian and naturalistic view of landscapes. The use of the landscape as a tool for heritage preservation in the context of the Bassari, Fula and Bedik cultural landscapes which are on the UNESCO World Heritage List is intended to break with a naturalistic view by integrating a social dimension into conservation approaches. However, this stated desire to recognise local practices is ambiguous. Heritage designation continues to be largely guided by international standards and a naturalistic approach often disconnected from local agricultural, forest farming or pastoral practices. The article examines the tensions between an institutional recognition of the role of societies in the creation of landscapes and an inherited view that limits recognition of this role when defining management and conservation policies.Cet article propose une analyse de la genèse et des évolutions des aires protégées en Afrique de l’Ouest, en particulier dans le contexte des savanes soudaniennes. Il s’appuie sur une approche croisée, combinant littérature scientifique, sources historiques, données cartographiques et enquêtes de terrain menées entre 2023 et 2024 dans la région de Kédougou, au Sénégal. L’étude met en évidence l’ancrage colonial des premières politiques de protection environnementale, centrées sur une vision utilitariste et naturaliste des paysages. Le recours au paysage comme outil de patrimonialisation, dans le cadre du Pays Bassari : paysages culturels Bassari, Peul et Bédik sur la liste du patrimoine mondial de l’Unesco, se veut en rupture avec une vision naturaliste, en intégrant aux logiques de conservation une dimension sociale. Cependant, cette volonté affichée de reconnaître les pratiques locales demeure ambiguë. La patrimonialisation reste largement guidée par des normes internationales et une logique naturaliste, souvent déconnectée des pratiques agro-sylvo-pastorales locales. L’article s’interroge ainsi sur les tensions entre la reconnaissance institutionnelle du rôle des sociétés dans la fabrique des paysages et le poids d’une vision héritée, qui limite leur prise en compte dans les politiques de gestion et de conservation
Cartographie du Réservoir Utile Maximal en eau des sols à partir des Référentiels Régionaux Pédologiques
No full textInternational audienceLe Réservoir en eau Utilisable (RU) des sols est la quantité d’eau qu’un sol peut retenir et restituer aux plantes. Cet indicateur dépend de la texture du sol, c’est-à-dire des proportions d’argiles, limons et sables, ainsi que de sa profondeur et de sa proportion d’éléments grossiers. La teneur en carbone du sol a également été identifiée comme prédicteur important du RU lorsqu’il est estimé par une fonction de pédotransfert (Román Dobarco et al., 2019). La disponibilité de données sur les sols augmente en France, notamment par l’effort de réalisation des Référentiels Régionaux Pédologiques (RRP) dans le cadre du programme « Inventaire, Gestion et Conservation des Sols » (IGCS) coordonné par le Groupement d’intérêt Scientifique Sol. Ces systèmes d’informations spatialisées sur les sols à l’échelle 1/250 000 présentent une base sémantique riche qui peut être valorisée à travers des cartographies thématiques de propriétés fonctionnelles des sols à l‘échelle régionale. Dans ce contexte, notre étude vise à proposer une procédure pour calculer et cartographier aisément et de façon quasi-automatique le RU à partir d’un RRP, sous la forme d’un un script en langage Python. Afin de minimiser les échecs de calcul dus à d’éventuelles données manquantes, le script implémente un arbre de décisions permettant de compléter la base de données en utilisant d’autres variables pédologiques disponibles ou à dires d’expert. Le script a été testé sur des jeux de données partiellement incomplets afin d’évaluer sa fiabilité en présence de données manquantes.L’application de ce script au RRP de Bretagne a permis de générer des cartes du RU estimé sur une épaisseur de sol de 1 mètre à partir de trois sources de données : (1) la base de données DoneSol du RRP avec une représentation de la valeur du RU par Unités Cartographiques de Sol ; (2) les données issues de la spatialisation des Unités Typologiques de Sol (Vincent et al., 2016) du RRP Bretagne projetées sur une grille raster au pas de 50 mètres et (3) les propriétés pédologiques à la même résolution dérivées par tranche de profondeur selon les spécifications GlobalSoilMap.Les cartes (2) et (3) du RU ont été comparées aux résultats préexistants, dont la carte du RU nationale à une résolution de 90 mètres (Román Dobarco et al. 2021), ainsi que la carte issue des données de SoilGrids. Cette étape rend compte de la pertinence des différents niveaux de précision en fonction des usages de l’information produite. De plus, l’utilisation de données locales exhaustives permet d’obtenir une carte du RU englobant la variabilité induite par les spécificités pédologiques régionales, telles que les sols issus de limons éoliens sur la frange nord de la région et jusqu’au centre de l’Ille-et-Vilaine, ou bien les Monts d’Arrée en Bretagne, dans le Finistère.Enfin, ce script offre une valorisation rapide et accessible des données des RRP, que l’on peut déployer à l’échelle d‘autres régions. La démarche employée dans notre étude ouvre également des perspectives quant à la complétion des bases de données, et au calcul de nouveaux indicateurs de qualité des sols
Réalisme des représentations graphiques des cochons et de l’élevage porcin dans la presse et l’édition jeunesse en France
No full textInternational audienceDu fait des règles de biosécurité (Grannec et Roguet, 2017) et de la faible proportion de Français comptant un éleveur de porc dans leur famille ou leur entourage proche, peu de personnes ont déjà visité un élevage de porcs. Aussi, la manière dont le grand public se représente cet élevage se base sur des informations issues de la presse, de documentaires, d’associations, etc. Deux visions sont notamment véhiculées : d’un côté une vision bucolique, type « Martine à la ferme », présentant des exploitations de petite taille avec des animaux en liberté, et de l’autre une vision industrielle et productiviste négative (Maquet et al., 2011). Chez les enfants, la consultation de livres est un moyen fréquent d’obtenir des informations sur les animaux. Ainsi, une enquête de la Chaire Bien-être animal auprès d’enfants de CM1 et CM2 (2023) montre que 31 % de ceux-ci consultent des livres sur les animaux plusieurs fois par mois, et 20 % au moins une fois par mois. Les livres ne sont pas l’unique source d’information et de loisir des enfants. En revanche, l’accès aux livres via les bibliothèques scolaires, de quartier ou municipales est très répandu. Aussi, nous avons décidé d’étudier le réalisme des représentations graphiques du cochon et de l’élevage porcin dont disposent les enfants de 0 à 11 ans pour se représenter l’élevage des porcs. Pour cela, nous avons choisi de nous baser sur les ressources disponibles dan