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Radioactive environmental dust (RED'air)
No full textFiche projet OHM Bassin Minier de ProvenceDans le cadre du projet RED’Air, l’IRSN Cadarache et le CEREGE ont réalisé conjointement des prélèvements dans l’environnement du site de stockage de résidus solides issus du traitement de la bauxite par la société Alteo à Gardanne. L’objectif était d’évaluer la contamination de l’atmosphère et des végétaux terrestres potentiellement issue de cette source
Guide d’accompagnement à l’évaluation de l’état de conservation des habitats benthiques marins – Natura2000 : ressources, protocoles et retours d’expérience du projet life Marha
No full textÉvaluer l’état de conservation des habitats marins constitue une étape essentielle pour mieux connaître, comprendre et préserver le fonctionnement des écosystèmes côtiers. Réalisée à la fois à l’échelle biogéographique et à celle des sites Natura 2000, ces évaluations permettent de répondre aux obligations de la Directive Habitats-Faune-Flore tout en orientant les actions de gestion vers le maintien ou le rétablissement d’un état de conservation favorable. Afin d’assurer la comparabilité et la fiabilité des résultats, ces évaluations doivent s’appuyer sur des méthodes standardisées, reproductibles et scientifiquement robustes. Les outils et les retours d’expérience du Life Marha présentés dans ce guide, notamment la démarche proposée par Delavenne & de Bettignies (2023) intégrant l’aspect fonctionnel des habitats marins, offrent aux gestionnaires un cadre méthodologique pour renforcer l’efficacité de leurs suivis et de leurs mesures de gestion. Ce guide constitue ainsi une compilation des ressources clés et retours d’expérience pour accompagner les gestionnaires dans leurs choix, faciliter la mise en œuvre d’actions adaptées et contribuer, à terme, à l’amélioration durable de l’état de conservation des habitats marins. Bien que les travaux se poursuivent pour affiner les connaissances et les outils disponibles, il marque une étape importante vers une gestion plus cohérente, intégrée et opérationnelle du patrimoine marin
Virtual City Simulator: A Scenario-Based Tool for Multidimensional Urban Flood Long-Term Vulnerability Assessment and Planning in Mediterranean Cities
No full textInternational audienceCities are increasingly vulnerable to flooding due to rapid urbanization and climate change, especially in Mediterranean climates. Although hydroinformatics, numerical modeling, and artificial intelligence can simulate and predict floods with high accuracy, critical gaps persist in assessing flood vulnerability, particularly in data-scarce environments. We present the Virtual City Simulator, a decision-making support platform that evaluates long-term multi-dimension vulnerability to flooding. It combines a synthetic Mediterranean urban model with a composite vulnerability to flooding of index based on four dimensions (social, economic, environmental, physical) and three components (exposure, susceptibility and resilience). We have developed the following: (i) a representative virtual Mediterranean city (500,000 inhabitants, 100 km 2 ; eight neighborhood typologies), (ii) a database with default values of 36 indicators for the eight typical neighborhoods, and (iii) a user-friendly RStudio/Shiny tool that integrates the virtual city and the database, with editable values for indicators and weights, that calculates the multidimensional vulnerability index to floods, and maps the results by dimension and in an integrated way, allowing comparability among scenarios. To illustrate the potential of the tool, the paper includes three case studies: (i) the business-as-usual scenario, using the default values of the indicators and weights of the database, where the most vulnerable neighborhood and dimensions of the virtual city are identified, (ii) the impact of implementing resilience measures in the previously identified vulnerable neighborhood, and (iii) the application of the tool to a neighborhood in a Mediterranean city (Ruzafa-Valencia), combining the available real data with the virtual city database
Ancient origin of an urban underground mosquito
No full textPosted February 05, 2025 on bioRxiv.International audienceUnderstanding how life is adapting to urban environments represents an important challenge in evolutionary biology. Here we investigate a widely cited example of urban adaptation, Culex pipiens form molestus , also known as the London Underground Mosquito. Population genomic analysis of ∼350 contemporary and historical samples counter the popular hypothesis that molestus originated belowground in London less than 200 years ago. Instead, we show that molestus first adapted to human environments aboveground in the Middle East over the course of >1000 years, likely in concert with the rise of agricultural civilizations. Our results highlight the role of early human society in priming taxa for contemporary urban evolution and have important implications for understanding arbovirus transmission
Beyond synteny: a scalable phylogenomics method for whole-genome duplication detection
No full textInternational audienceGene duplication is a fundamental driver of species adaptation and the evolution of new functions, making the reconstruction of historical duplication events crucial for understanding evolutionary processes. Whole-genome duplications (WGDs), which duplicate all gene families simultaneously, have profoundly influenced the evolution of plants, yeast, and vertebrates. Genome-scale data, such as syntenic blocks and gene family counts, are commonly employed to infer WGDs. However, detecting ancient WGDs remains challenging, as their genomic signatures are often overshadowed by extensive rearrangements and gene losses. Phylogenetic reconciliation methods between species and gene trees offers a potential means of identifying such ancient events, but frequently as-1 sume independence among gene families. This can lead to missed detections of WGDs, where gene duplications are inherently interdependent. Phylogenomics reconciliation addresses this challenge by reconciling multiple gene families at once. Unfortunately, existing models often constrain the space of possible reconciliations, overlook gene losses resulting from fractionation, or depend on conserved synteny across multiple species. This limits the number of genes that can be analyzed concurrently.In this work, we explore a phylogenomics reconciliation model that avoids synteny reliance, explicitly incorporates gene losses, and permits flexible remapping of duplications. Reconciliation under this model is NP-hard, and existing algorithms lack the scalability for large-scale datasets. To address this need, we present novel algorithmic strategies that efficiently handle tens of thousands of gene trees-a level of scalability previously unattained. We also evaluate our approach against existing methods. Experiments on both simulations and real data show that traditional LCA-mapping can yield incorrect WGD predictions after fractionation, whereas our approach is more robust. By comparing predictions using true and reconstructed gene trees, we further show that reconstruction errors greatly affect method performance, and that gene tree correction is necessary for reliable results. Real data tests also reveal that our approach can recover WGDs missed by other reconciliation methods.</div
Botascopia: a digital setup for generating low tech plant field guides
No full textPlant field guides are portable reference books or digital tools designed to help various users identify plant species in a given area and find out about their morphology, ecology and usage. We present Botascopia, a combination of digital tools that automatically produce low-tech field guides in the form of printed paper booklets containing species description sheets associated with an identification key. These are analogous to floras adapted to local ecosystems, such as gardens, parks, school yards or campuses. Botascopia contains a participatory knowledge base with detailed descriptions of plant species. It uses computational languages to express different perspectives on plants held by expert botanists and novice observers, for example, and the translations between them. This setup therefore offers a solution to the usual challenge of balancing precise vocabulary with making botanical knowledge accessible beyond expert communities. We tested this approach during botanical field sessions with diverse audiences, providing them with personalised, automatically generated printed booklets. This experiment explores how combining low- and high-tech approaches can contribute to the study of the relationships between technology, humans, and plants in the Anthropocene
Mise à jour des estimations démographiques et des effectifs de la population de loups en France lors de l'hiver 2024/25
No full textLa population de loups (Canis lupus) en France fait l'objet d'un suivi annuel réalisé par le Réseau Loup-Lynx, piloté par l'Office Français de la Biodiversité. Ce rapport actualise les paramètres démographiques et les estimations d'effectifs à la suite de la campagne de terrain de l'hiver 2024/25. Comme déjà appliqué depuis l'hiver 2023/24, la collecte des données s'appuie sur un plan d'échantillonnage définissant, pour des mailles de 10*10km, des objectifs de récolte d'indices biologiques afin d'homogénéiser la prospection dans les zones de présence historiques. Le génotypage de l'ADN issu des indices biologiques collectés sur tout le territoire français (fèces, poils, urines, sang et dépouilles des loups morts) permet d'obtenir l'identité génétique des individus. Cette identité constitue la donnée de base pour l'estimation des paramètres démographiques et des effectifs. Comme les années précédentes, les méthodes de capture-recapture ont été utilisées pour prendre en compte la détection partielle et hétérogène des individus de la population. Les estimations d'effectifs montrent que le nombre de loups en France lors de l'hiver 2024/25 se situe vraisemblablement entre 989 et 1187 individus. Ces deux valeurs correspondent aux bornes basse et haute de l'intervalle de confiance à 95%. Bien que l'effectif moyen montre une légère hausse -passant de 1013 lors de l'hiver 2023/24 à 1082 lors de l'hiver 2024/25 -il n'est pas possible de conclure à une augmentation des effectifs entre ces deux années puisque les intervalles de confiance (IC) associés se chevauchent (2023/24 : 920-1125 ; 2024/25 : 989-1187). Les conclusions sur la tendance démographique de la population doivent se faire sur des séries pluriannuelles pour identifier les trajectoires démographiques des populations, particulièrement au vu du degré d'incertitude associé à ces estimations. La connaissance des paramètres démographiques éclaire aussi ces tendances. La mise à jour des estimations de survie annuelle confirme la dynamique observée précédemment : le taux de survie passe de 71 % (IC à 95 % : 67-76 %) sur la période 2014-2018 à 66 % (IC 95 % : 59-73 %) sur la période 2019-2025. Cette dernière période correspond au changement de régime de prélèvement dérogatoire qui est passé d'environ 10% de la population sur la période 2014-18 à 19% en 2019-25. Avec de tels niveaux de survie, une stabilisation de la population est attendue, ce que semble refléter les estimations d'effectifs des quatre dernières années
Autant rapporte le vent ! Comprendre la taxe sur les éoliennes en mer de France
No full textAs much as the wind brings! Understanding the tax on offshore wind turbines in France Context: -Wind energy (wind power), a renewable energy source that guarantees the energy transition. -15 wind farm projects on the French coast. -40 gigawatts of electricity expected by 2050. 50% 35% 5% 10%Autant rapporte le vent ! Comprendre la taxe sur les éoliennes en mer de France Contexte: -L'énergie du vent (éolien), une énergie renouvelable garante de la transition énergétique. -15 projets de parcs éoliens sur le littoral Français. -40 gigawatts d'électricité attendus d'ici 2050. 50% 35% 5% 10%</div
Evaluating Deep Learning Architectures for 3D Point Cloud Classification of Mammalian Bones
No full textInternational audienceBone classification is fundamental in paleontology, evolutionary biology, and museum collection management, where natural history museums house billions of specimens documenting biodiversity. Traditional bone identification has relied on specialist expertise and manual methods, but with rapid digitization of collections and advances in 3D scanning, computer-assisted approaches are increasingly adopted. Among digital formats, 3D point clouds (Qi et al. 2017a) produced using scanning techniques such as surface scanning, photogrammetry, and computed tomography (CT) have become preferred representations as they preserve fine structural details while remaining computationally efficient. However, the absence of inherent ordering in 3D point space poses fundamental challenges for conventional deep learning models, and scaling manual classification to vast digital collections remains problematic.This study evaluates and compares state-of-the-art deep learning architectures, specifically designed for 3D point cloud processing, on mammalian bone classification. We assembled a dataset of 1,641 3D bone specimens representing 14 bone-type classes, 302 species, 203 genera, 40 families, and 28 orders, obtained through digitization as part of the e-COL+ project* , which aims to digitize a wide range of zoological specimens in 3D and is led by the MNHN, Paris. This taxonomic breadth increases morphological variability and provides a valuable benchmark for evaluating generalization capacity. All 3D meshes were standardized by converting to point clouds, downsampled to 1,024 points using Furthest Point Sampling (FPS) algorithm, and normalized to unit spheres (Fig. 1)
Enhanced visible-light degradation and mineralization of Bisphenol A using Cu-doped TiO2 photocatalysts: characterization, effectiveness, mechanism and DFT insights
No full textInternational audienceThis study reports a new visible light-driven strategy for the degradation and mineralization of bisphenol A (BPA) using copper-doped TiO2 photocatalysts. BPA is an emerging contaminant of significant environmental and health concern. A series of Cu-doped TiO2 catalysts with varying copper contents was synthesized via the sol-gel method and characterized using XPS, XRD, SEM-EDS, N2 physisorption, and UV-vis spectroscopy to evaluate their structural, morphological, and optical properties. Results confirmed that copper incorporation enhanced visible-light absorption and improved electron-hole pair separation, resulting in enhanced photocatalytic activity and stability. The band gap energy decreased with increasing copper content, from 2.97 eV for pure TiO2 to 2.88, 2.41, and 2.28 eV for 1%, 5%, and 10% Cu-TiO2, respectively, as validated by Density Functional Theory (DFT) calculations. Among all J o u r n a l P r e -p r o o f prepared materials, Cu(5%)-TiO2 exhibited the best photocatalytic performance, outperforming both pure TiO2 and other Cu-TiO2 variants. Under optimal conditions (5 mg/L BPA, pH 7, and 1 g/L catalyst dosage), 96.2% BPA removal and 77.9% mineralization were achieved. The catalyst maintained excellent reusability over four successive cycles with minimal activity loss.Scavenger experiments identified photogenerated holes (h + ) and hydroxyl radicals (OH ) as the main reactive species. UHPLC-MS analysis enabled the identification of intermediate products and the proposal of a plausible BPA degradation pathway. Furthermore, Cu(5%)-TiO2 showed high degradation efficiency for other emerging pollutants and across different water matrices, demonstrating its potential for sustainable industrial wastewater treatment applications.</div