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Changes in phenology mediate vertebrate population responses to temperature globally
No full textInternational audiencePhenotypic responses to climate affect individual fitness, but the extent to which this translates into effects on population dynamics remains poorly understood. We assemble 213 time series on phenotypes and population sizes of wild vertebrates globally and match them with local climate data. Our meta-analysis shows that morphological traits are mostly climate insensitive. However, phenology is earlier in warmer-than-average years, which contributes positively to population growth in most species. At lower latitudes, temperature has weaker effects on phenology but stronger direct negative effects on population growth, likely because these populations are less capable of tracking climate via plasticity. Variation in the phenology-mediated effect of temperature on population growth cannot be explained by latitude, generation time, migratory mode, or diet. This suggests that simple relationships between species characteristics and population responses to warming may not occur in nature. Instead, we may need to embrace ecological complexity by considering local-scale predictors that capture intra-specific variation
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
Can Widely Used Methods Be Turned Into eDNA Samplers for Ground-Dwelling Arthropods? Insights From Two Pilot Studies in West European Salt Marshes
No full textInternational audienceThe pressing demand for arthropod preservation, coupled with a decline in taxonomic expertise and available resources, calls for innovative strategies in assessing biodiversity. Metabarcoding and more recently environmental DNA (eDNA) metabarcoding have been shown to be a promising technique for identifying terrestrial arthropods. This research evaluated the efficacy of two conventional sampling approaches, adapted for metabarcoding surveys, in monitoring the diversity of spiders (Araneae) and beetles (Coleoptera) within salt marsh environments. The methods tested were suction sampling (G-vac) and modified pitfall traps (NDC, a non-destructive DNA collector). Through two pilot experiments in salt-marsh environments, we found that both methods successfully identified diverse arthropod communities, though discrepancies with traditional morphological identification highlighted the strengths and limitations of molecular approaches. Suction sampling excelled in detecting taxa such as Lepidoptera and Salticidae, which are often overlooked by physical collections, whereas modified pitfall traps performed well for dung beetles but faced challenges with wolf spiders (Lycosidae). Our findings underscore the importance of tailoring eDNA protocols to specific taxonomic groups and ecosystems, particularly through strategic primer and DNA fragment selection. While traditional methods remain indispensable for comprehensive biodiversity inventories, eDNA metabarcoding offers a powerful complementary approach for detecting cryptic or undersampled taxa. This study emphasizes the need for the targeted adaptation of eDNA techniques to specific taxonomic groups and ecosystems. Primer choice and DNA fragment selection significantly influenced detection efficiency, with broader primers reducing taxonomic resolution and amplifying bias. Although traditional methods remain critical for comprehensive biodiversity inventories, bulk and eDNA metabarcoding offer a complementary tool. These findings contribute to advancing arthropod monitoring tools and aiding conservation efforts amidst declining entomological resources
L'épopée engagée et désengagé des marcheurs de Lianda (Université Nationale du Sud-Ouest): Réfugiés universitaires et récits des migrations forcées en Chine au XXe siècle
No full textStandardizing plant damage datasets via EPPO taxonomy: A label harmonization approach using large language models
No full textInternational audiencePests and diseases threaten global crop yields, yet the absence of standardized plant-damage datasets limits progress toward general, robust diagnostic tools. Existing resources differ widely in label conventions and scope, hindering interoperability and model generalization. We introduce a fully automated method for harmonizing plant-damage labels across heterogeneous datasets by mapping them to the European and Mediterranean Plant Protection Organization (EPPO) taxonomy. The approach uses large-language-model (LLM) embeddings to capture semantic similarity among label terms, including synonyms, multilingual variants, and vernacular names.Across multiple mapping strategies, embedding-based similarity using OpenAI’s text-embedding-3-large provided the best performance, reaching an F1 score of 0.836 at optimal thresholds and outperforming string-based Levenshtein matching and other LLM baselines. Applying this method, we unified five expert-curated datasets, including the newly released ePhytia collection, yielding 79,808 images mapped to 1895 EPPO-aligned classes.To assess the value of this harmonization, we finetuned a generalist pretrained Vision Transformer for large-scale plant-damage identification. Models trained on LLM-aligned labels consistently surpassed those trained with edit-distance mappings. On independent EPPO test images, our best model achieved 19.4% top-1 accuracy across 1091 classes and 33.1% on the 100 most common classes, demonstrating feasibility at unprecedented label scale. In-dataset evaluation reached 55.8% top-1 accuracy.By grounding label harmonization in an international standard, this work delivers the first large-scale, taxonomy-compliant dataset for in-field plant-damage recognition and establishes a foundation for interoperable diagnostic tools, farmer-facing mobile systems, and plant-health monitoring. We release both the harmonized dataset and the new ePhytia images to support future research
Influência das redes sociotécnicas na diversidade de sistemas agroflorestais de cacau no nordeste do Pará, Brasil
No full textSource Agritrop Cirad (https://agritrop.cirad.fr/617031/) * Autres projets (id;sigle;titre): ;Sustenta & Inova;(EU) Restaurer les zones altérées dans les territoires amazoniens//International audienceThis article analyses the influence of the socio-technical networks associated with agroforestry systems (AFS) on the diversity of cacao agroforestry systems (CAFS) in the Eastern Brazilian Amazon, in the municipalities of Irituia and Tomé-Açu. Fieldwork was carried out through semi-structured interviews, participatory activities and agrarian diagnostics. Three types of CAFS were identified: Group 1 was “market-oriented”; Group 2 was related to “food sovereignty”; and Group 3 was “syntropic”. The socio-technical networks appeared fragmented: an institutional network in Tomé-Açu focused on cacao intensification, while an agroecological network, predominantly in Irituia, pertained to cooperatives and local associations. Group 1, as part of the institutional network, uses intensive techniques. The second and third groups adopt alternative strategies: Group 2 uses crop diversification and certified markets, while Group 3 focuses on syntropic agriculture to regenerate degraded land. Connecting these networks could facilitate knowledge and practice exchanges, contributing to more resilient and sustainable production systems.Este artigo analisa a influência das redes sociotécnicas associadas aos sistemas agroflorestais (SAFs) sobre a diversidade dos sistemas agroflorestais cacaueiros (SAFCs) na Amazônia Oriental, nos municipios de Irituia e Tomé-Açu. O trabalho de campo foi feito por entrevistas semiestruturadas, atividades participativas e diagnósticos agrários. Três tipos de SAFCs emergiram da análise: Grupo 1 “orientado para o mercado”; Grupo 2 “soberania alimentar”; e Grupo 3, “sintrópico”. As redes sociotécnicas aparecem fragmentadas: uma rede institucional em Tomé-Açu, voltada para a intensificação do cacau, e uma rede agroecológica, predominante em Irituia, vinculada a cooperativas e associações locais. O grupo 1, inserido na rede institucional, adota técnicas agrícolas intensivas. Os grupos 2 e 3 empregam estratégias alternativas: o grupo 2 prioriza a diversificação de culturas e mercados certificados, enquanto o grupo 3 se concentra na agricultura sintrópica para regenerar áreas degradadas. Uma melhor articulação entre essas redes poderia facilitar a troca de conhecimentos e práticas, contribuindo para sistemas de produção mais resilientes e sustentáveis
« Perdus dans Prague sur les pas de Kafka et Hrabal. Une promenade germano-tchèque et décalée au bord de la Vltava. », Préface.
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Design and manufacturing method for the production of soft tensegrity structures and mechanisms
No full textInternational audienceSoft tensegrities are prestressed assemblies of soft elastic cables and rigid bars. They combine the interest of tensegrities, with high payload to weight ratio, stiffness tunable by the internal prestress, and the interest of soft robots with a large compliance thanks to the use of soft elastic cables. Their use is hampered by their difficult manufacturing due to a complex spatial arrangement of cables and bars and the use of soft materials for cables. In this paper, we propose a method for the design and manufacturing of both tensegrity structures and tensegrity mechanisms. We consider their production using bi-material additive manufacturing and silicone deposition. The proposed method relies on the design of specific tooling simultaneously with the tensegrity. This tooling eases the control of the tensegrity geometric arrangement and makes possible the introduction of prestress in the structure. The method is then applied to obtain planar and spatial soft tensegrity structures and a soft tensegrity mechanism. The capability to obtain variable level of prestress, and how it can be leveraged to achieve variable stiffness is also shown
A propos d'une politique des frontières
No full textCe texte reprend une communication à la journée d'hommage, organisée par le laboratoire CRISES de l'université de Montpellier Paul-Valéry, à la mémoire du Pr Jean-Daniel Causse, son directeur, décédé en activité en 2000.Cette journée était organisée autour des œuvres de Jean-Daniel Causse. Ici c'est son "Introduction à une politique des frontières, tracer, traverser, effacer" qui a servi de fil directeur avec une application au cas du Kosovo