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Crop residues moderately influence cumulative N2O emissions through their carbon to nitrogen ratio in a 12-year experiment in northern France
No full textInternational audienceCrop residues and their management are central to the performance of cropping systems. However, we lack information on the extent to which crop residues influence their N₂O emissions, especially over the long term. This knowledge is key as it determines if benefits from crop residue management such as increased carbon storage or soil and water preservation should be weighed against potential stimulation of N 2 O emissions. To lessen this gap, we investigated the effect of crop residue quantity (dry matter yield ranging from 0.29 to 11 t•ha -1 ) and quality (C:N ranging from 8 to 157) on N 2 O emissions and compared it to the effects of other key drivers related to environmental conditions and management practices, such as soil moisture, temperature, and fertilization. We relied on a 12-year dataset of N 2 O emissions from an arable cropping experiment in northern France and implemented an original approach combining definition of "restitution cycles" and use of both linear regression and machine learning algorithms to predict N 2 O emissions at that scale. This allowed to assess the contribution of the various drivers of these emissions, among which crop residue and their management. Our results show that the main drivers of cumulative N 2 O emissions were the amount of mineral nitrogen fertilizer and restitution cycle length. Crop residue characteristics had a relatively minor effect. Among the residue quality indicators, only crop residue C:N ratio affected N 2 O emissions. Tillage, temperature, and water-filled pore space had no detectable or systematic impact. These findings, which are original in terms of the cropping system scale considered, suggest that crop-residue management is not likely to significantly affect N 2 O emissions from arable cropping systems in northern France. They open up opportunities for agricultural decision-making without concern for increased N 2 O emissions as an unwanted trade-off
African zoonotic schistosomiasis: a paradigm shift
No full textInternational audienceIn Asia, Schistosoma japonicum infects humans and many animal species, making it a zoonotic disease. In Africa, the two major species infecting humans are Schistosoma mansoni and Schistosoma haematobium, which cause mesenteric and urogenital schistosomiasis, respectively. Despite the significance of these parasitic infections for human health, few studies have examined the zoonotic aspects of these parasites. In the initial section of this article, we examine the advancements made in analysing the zoonotic characteristics of S. japonicum, with a particular emphasis on the diverse scenarios observed in the field. We also review the role of rodents and non-human primates in transmitting S. mansoni and the emerging importance of cattle and rodents in hybrid schistosomiasis involving S. haematobium and Schistosoma bovis (a livestock and rodent parasite). Second, we examine the genetic diversity of these hybrid forms across their distribution in West Africa. Hybrid forms exhibit considerable diversity across all spatial levels, ranging from the transmission site to the national scale. Ultimately, we aim to explore the implications of zoonotic urogenital schistosomiasis in relation to the role of each host in its transmission, together with parasite gene flow, parasite diversity and parasite virulence. This article is part of the Royal Society Science+ meeting issue ‘Parasite evolution and impact in action: exploring the importance and control of hybrid schistosomes in Africa and beyond’
Transcriptomic plasticity in hybrid schistosomes can contribute to their zoonotic potential
No full textData accessibility: Sequencing data from Schistosoma bovis, hybrids and introgressed worms infecting sheep are available at the NCBISRA under the BioProject accession number PRJNA1199762.International audienceHybrids between Schistosoma haematobium and Schistosoma bovis contribute to human and animal infections, highlighting complex interspecies interactions that facilitate schistosomiasis transmission. Schistosoma bovis infects multiple ruminant hosts, promoting cross-species transmission and increasing zoonotic risk. This study explores transcriptomic plasticity as a mechanism enabling hybrid schistosomes to adapt to different definitive hosts. We analysed two contexts: (1) introgressed S. haematobium × S. bovis hybrids, which exhibited higher virulence in sheep than parental S. bovis; and (2) S. bovis infecting different mammalian hosts. Introgression, the transfer of genetic material between species through hybridization and repeated backcrossing, was associated with 366 differentially expressed genes (4% of coding genes) between introgressed hybrids and S. bovis in sheep. Additionally, S. bovis showed host-dependent transcriptomic changes, with 30% of genes differentially expressed between infections in hamsters and sheep. Enriched biological processes shared across introgression and host adaptation included nuclear mRNA catabolism and inner mitochondrial membrane organization, indicating increased gene expression plasticity and metabolic adaptation to environmental stress. These findings suggest that transcriptomic plasticity enhances the adaptability of S. bovis and hybrid worms, increasing their zoonotic potential. This raises concerns for schistosomiasis control, as such plasticity could expand transmission capacity and complicate intervention strategies.This article is part of the Royal Society Science+ meeting issue ‘Parasite evolution and impact in action: exploring the importance and control of hybrid schistosomes in Africa and beyond’
Receptiveness of the wine industry to fungus-resistant grape varieties in the south of France
No full textInternational audienceThe adoption of fungus-resistant grape varieties (FRGs) represents a promising pathway for steering viticulture towards more sustainable production methods by reducing the use of phytosanitary inputs. At the time of writing, the dissemination of these varieties remains limited, partly due to constraints within the wine industry (i.e., cost of planting and cultivar limitations associated with Protected Designation of Origin).This study was conducted with commercial wines made from two types of grape: Vitis vinifera and FRGs. A panel of 96 participants from the wine industry in the Occitanie region (south of France) conducted sensory evaluations. The panel performed the evaluations both blind and having been informed about type of grape in a combination of short CATA (Check-All-That-Apply) sessions followed by questions exploring their interest in FRGs and expected plantations in the coming years.The results of the sensory analyses underlined the absence of any notable difference in liking or in the sensory profiles of the wines, whether tasted blind or not. Indeed, disclosure of the type of grape used to make the wines did not alter participants’ perceptions or evaluations. Furthermore, the analysis of questionnaire data revealed a typology of three adopter profiles: i) “sceptics”: older professionals from private wineries who were generally unfavourable towards the adoption of FRGs, ii) “receptives”: cooperative members who showed measured support for innovation, and iii) “observers”: young, non-decision-making individuals with heterogeneous opinions. This industry panel predicted that there could be 25 % of vineyard areas planted with FRGs in Occitanie within the coming 30 years.This study offers insights into the future adoption of this new plant material within the wine industry
One water? In pursuit of water circularity in Moroccan Oases
No full textSource Agritrop Cirad (https://agritrop.cirad.fr/616736/) * Autres projets (id;sigle;titre): ;MASSIRE;(ITA) Innovations rurales et eau dans les territoires sud du Maghreb//International audienceWater resources development and the intensification of water uses have profoundly altered water circulation in the arid river basins of southeast Morocco, leading to water reallocation and scarcity. Four case studies show how the State and farmers are adapting, often unsustainably, to the created water scarcity, including by promoting local water circularity. This paper argues that incorporating the principles of the circular economy 'Reduce' and 'Replenish' might be helpful to reconnect surface and groundwater at the explicit condition to reduce anthropogenic pressure on water resources and consider water circulation at the basin level
Optimisation de la qualité d'application et gestion du risque de dérive avec les drones de pulvérisation basées sur un contröle des taille de gouttes multigraduée.
No full textInternational audienceUnmanned aerial spraying systems (UASS) are widely used in agriculture; however, spray drift remains a significant barrier to their broader adoption. Conventional drift-control measures—such as nozzle optimization and adjuvants—primarily act by altering droplet size. This study introduces a dynamic droplet-size control approach for UASS equipped with centrifugal nozzles to balance spray quality and drift risk. We established the relationship between nozzle rotational speed and droplet size and developed an embedded, variable droplet-size UASS. The system utilizes differential RTK to acquire real-time UAV position data, enabling dynamic adjustment of droplet size during operation. Field trials demonstrated the system’s stability and reliability: the UASS responded promptly to ground commands for droplet size changes and accurately logged the corresponding adjustment locations. Data analysis indicated that increasing droplet size markedly reduces drift volume and droplet density in the downwind drift zone. Relative to a baseline without droplet-size control, a three-stage adjustment strategy reduced the drift ratio by 89.18%, shortened the 90% drift distance to 3.36 m, and delivered the highest drift-mitigation rate. To minimize drift while maintaining effective penetration, we propose using the very fine (VF) droplet size (82.4 μm) for the first two flight paths and increasing to 300–350 μm for the third. These findings demonstrate that dynamic droplet-size adjustment via pulse-width modulation can effectively reduce drift. External factors, such as wind and terrain, continue to be influential, underscoring the need for further research to refine and optimize drift-control strategies under diverse operating conditions
Proposition d’un guide réflexif pour la construction de démarche d’innovation collective dans les filières agroalimentaires: Document de travail
No full textLes sciences économiques et de gestion s’accordent à définir tout système d’innovation comme un réseau d’acteurs qui interagissent pour le développement d’une innovation grâce à la mobilisation de ressources (financières, humaines et matérielles) et au sein de règles d’action partagées. Quatre dimension clés structurent la performance de tout système d’innovation : la pertinence et cohérence des acteurs en présence ; l’intensité des interactions les liant ; les règles d’action collective (ie. régles du jeu) qui déterminent leur capacité à agir (on distingue souvent les institutions formelles et plus informelles liées aux routines et croyances) ; les ressources leur permettant d’agir (dénommés aussi infrastructures matérielles et non-matérielles). Analyser chacune de ces dimensions est reconnu comme trop complexe. C’est pourquoi il est plus simple de partir d’une catégorisation d’actions concrètement réalisées par les acteurs afin d’évaluer leur capacité d’innovation. Ce guide propose une catégorisation en 8 fonctions-clés pour évaluer et accompagner la performance des filières agroalimentaires à innover : entrepreneuriat, construction de marchés, mobilisation de ressources, extension du réseau, gouvernance et coordination, accroissement de la notoriété, développement et diffusion des connaissances, direction du changement. Le guide permet d’aborder chacune de ces fonctions au travers d’un ensemble de questions pour guider la réflexion d’une stratégie d’innovation pour tout opérateur des filières
Chapitre 5. Pas de relationalité sans solidarité. La fabrique de la solidarité écologique : affects, relations et assemblages pour la gouvernance des territoires vivants
No full textChapitre 5International audienceCe chapitre interroge l’impasse des gouvernances environnementales fondées sur des savoirs abstraits, incapables de produire des actions transformatrices et de résoudre des conflits qui opposent des mondes vécus. En mobilisant les savoirs situés, l’affect, l’adaptation affective et la « connaissance qui affecte », les auteurs proposent de requalifier la solidarité écologique : d’un principe juridique et cognitif à un affect émergent. Par une approche deleuzo-guattarienne de l’assemblage, la solidarité devient une intensité ressentie de l’interdépendance, produite par l’alignement de perspectives hétérogènes (scientifique, agricole, cynégétique, conservationniste). L’étude des marais de Camargue montre comment des pratiques de co-production (gestion concertée de l’eau, pâturage, suivis partagés) peuvent générer un « monde commun » et ouvrir sur des dispositifs durables (pactes socio-écologiques, arènes délibératives des vivants). Elle plaide pour une gouvernance relationnelle, attentive aux médiations matérielles et sensibles, où faciliter la rencontre compte plus que décider, afin d’instituer la solidarité
Les nouvelles intendances environnementales : coopérer, « hacker », jouer la transformation écologique dans nos territoires
No full textInternational audienceCet article propose une restitution d’une série de résidences de réflexions transdisciplinaires sur les « Nouvelles intendances des territoires » et sur les « Territoires vivants » dans le contexte du changement climatique et de la transition écologique. Ces résidences, initiées et réalisées de 2021 à 2024 dans le cadre des différentes éditions du Festival « Agir pour le Vivant » à Arles, ont exploré des approches innovantes de gouvernance, de participation citoyenne, et de relations entre humains et non-humains. Divers chercheurs ou experts en écologie, agronomie, sciences sociales et humanités environnementales, architecture et conservation de la nature mais aussi des élus et activistes ont présenté des études de cas et conduit des analyses croisées. Les défis de la confiance, du piratage des règles, du dialogue, de la prise en compte des dimensions spirituelles et émotionnelles, et du renouvellement des récits et des modes de penser sont identifiés. Le théâtre-forum apparaît comme un outil pertinent pour jouer, délibérer au sujet des enseignements de ces résidences et pour favoriser la rencontre entre l’action collective et l’action publique
Silage as a Feasible Technique for Calabash Tree ( Crescentia cujete ) Fruit Conservation: Evaluation of Different Mixtures and Alternatives
No full textInternational audienceThis research was aimed at evaluating the efficiency of silage technique with or without additional ingredients for conserving the fruit of the calabash tree ( Crescentia cujete ) as a source of food for cattle in the tropical dry forest. Five treatments were distributed in a completely randomized design, following a 5 × 5 factorial scheme with five treatments and five conservation times (7, 14, 28, 56, and 90 days) in order to understand, not only the effect of treatments but also the effect of time on the assessed fermentation and quality parameters. Hence, experimental treatments were defined as follows: T0, consisting of unground and not ensiled fruits; T1, ensiled ground fruit with no additives; T2, ensiled ground fruit with 1.5% of common salt (NaCl) addition; T3, ensiled mixture of ground fruit and calabash tree foliage in a fresh basis of 30:70 fruit‐to‐roughage ratio; and T4, ensiled mixture of ground fruit and Angleton ( Dichanthium aristatum ) hay in a fresh basis of 50:50 fruit‐to‐roughage ratio. The fermentative profile (i.e., pH, buffer capacity, NH 3 ‐N, and organic acid concentrations), nutritional value, and losses (i.e., fresh matter, dry matter (DM), nutrients, and gas) were determined. Not ensiled calabash tree fruit (T0) showed undesirable conservation characteristics, with the highest pH, the highest losses, and the poorest nutritive value after 90 days. Inclusion of forage in silage in treatments T3 and T4 increased the DM and the neutral detergent fiber (NDF) content compared to treatment T1. This dramatically reduced the specific density in treatment T4, which allowed fungus to appear and spoil the silage, resulting in a poor fermentative profile. T1 and T2 showed the lowest total losses, followed by T3. They also showed the highest concentrations of lactic acid and the lowest pH values, despite their high buffering capacity. The hard shells of the fruits were not sufficient to preserve the pulp and its nutritional value for more than 28 days. The addition of common NaCl did not improve the fermentative profile or nutritive value, so it is not necessary. This study has demonstrated the feasibility of silage technique as a method for preserving calabash tree fruit and suggest fruit silage without any additives followed by silage of ground fruit and calabash tree foliage mixture (30:70 fruit‐to‐roughage ratio) as efficient alternatives for preserving these feeds to supplement ruminant diets during dry season shortages in tropical farming systems. Further researches are necessary to evaluate the reproducibility and scalability of these results