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Handbook of protocols for standardized measurements of floral traits for pollinators in temperate communities
No full textInternational audienceFloral traits describe organs or structures directly related to plant reproduction, and they are essential to understanding plant–pollinator interactions, notably for conservation purposes. The growth of plant trait‐based approaches lies in the availability of data shared by the international research community on dedicated platforms, as well as in protocols compiled in handbooks on how to measure these traits in a standardized way. Floral traits are important pieces that are missing from these handbooks, likely due to the complexity of flower morphology. Here, we present a handbook of standardized protocols dedicated to floral traits that can be applied to a wide set of temperate plant species to quantify these traits at the scale of plant communities. The 24 floral traits are grouped into three categories: visual and olfactory cues, accessibility and resources. We also provide four additional features related to flower abundance and phenology that we recommend measuring to scale up individual species' trait values to overall plant communities. By collecting these floral traits in a standardized way, we promote applications in the context of community ecology to predict the diversity of pollinator communities, identify the effects of environmental changes and study plant–pollinator networks.Les traits floraux décrivent des organes ou des structures directement liés à la reproduction des plantes et sont essentiels pour comprendre les interactions entre les plantes et les pollinisateurs, notamment à des fins de conservation. Le développement des approches basées sur les traits des plantes repose sur la disponibilité de données partagées par la communauté scientifique internationale sur des plateformes dédiées, ainsi que sur des protocoles rassemblés dans des guides expliquant comment mesurer ces traits de manière standardisée. Les traits floraux constituent des éléments importants manquants dans ces guides, probablement en raison de la complexité de la morphologie des fleurs. Ici, nous présentons un guide de protocoles standardisés dédiés aux traits floraux, applicable à un grand nombre d'espèces végétales tempérées afin de quantifier ces traits à l'échelle des communautés végétales. Les 24 traits floraux sont regroupés en trois catégories : signaux visuels et olfactifs, accessibilité et ressources. Nous proposons également quatre caractéristiques supplémentaires liées à l'abondance et à la phénologie des fleurs, dont nous recommandons la mesure afin d'extrapoler les valeurs des traits de chaque espèce à l'échelle des communautés végétales. En collectant ces traits floraux de manière standardisée, nous favorisons leur application dans le domaine de l'écologie des communautés afin de prédire la diversité des communautés de pollinisateurs, d'identifier les effets des changements environnementaux et d'étudier les réseaux plantes‐pollinisateurs
Structure from motion used to revive archived aerial photographs for geomorphological analysis: an example from Mount Meager volcano, British Columbia, Canada
No full textInternational audienceHigh resolution topographic modeling has become more accessible due to the development of Structure from Motion (SfM) image matching algorithms in digital photogrammetry. Large archival databases of historical aerial photographs are available in university, public, and government libraries, commonly as paper copies. The photos can be in poor condition (i.e. deformed by humidity, scratched, or annotated). In addition, the negatives, as well as metadata, may be missing. Processing such photos using classic stereo-photogrammetry is difficult and, in many instances, impossible. SfM can be applied to these photosets to access the valuable archive of geomorphic changes over the past century. In this paper, we illustrate the utility of the SfM technique using 568 digitized vertical aerial photographs of Mount Meager volcano, located in southwest British Columbia, Canada. We use the aerial photographs, which span the period from 1947 to 2006, to track glacier and glacier-landslide interactions on the volcano. Over this period, glaciers have thinned and retreated, interrupted by minor advances in the 1960s and 1970s. Landslides are frequent on the volcano and contribute to debris cover on the glaciers affecting the ablation process. SfM processing of the aerial photographs allowed us to unlock geomorphic information and reconstruct landscape change that would otherwise have been impossible. The results from SfM provide a visually effective way of presenting landscape change to a broad public audience, as a form of virtual geoheritage. The approach can thus be broadly applied in scientific and professional practices for improving land planning and hazard management.</div
Ethnoecology of desert truffles hunting: A cross-cultural comparative study on practices and perceptions in the Mediterranean and the Near East
No full textInternational audienc
Diffusion of constructed resources and specialism promote facilitation in spatial systems
No full textInternational audienceSessile organisms, such as plants, contend with locally limiting nutrients and neighbours. By consuming nutrients or increasing local concentration by niche construction, they alter the conditions of growth in their local environment. Diffusion of resources alters the interaction sign between two neighbours usually thought to compete for resources. We investigate conditions under which the positive effect of niche construction outweighs the negative effect of competition. Following the experimental design of facilitation experiments, we model patches connected by a flow of resources and ask whether the presence of a niche constructor in one patch eases the colonisation of the other by a conspecific or heterospecific organism. The net interaction sign between a constructor and a coloniser depends on the niches of the two organisms, the diffusion of resources, and the type of niche construction. Niche constructors have a positive effect on neighbouring organisms when niches are sufficiently differentiated, and when the constructed resource diffuses more than the non‐constructed resource. Our work proposes mechanisms for the emergence of facilitation, which is increasingly recognised as a key process structuring plant communities. We discuss the implications for the spatial structure of plant communities and their functioning, including in an agricultural context
Community-Driven Code Comparisons for Simulations of Fluid-Induced Aseismic Slip
No full textInternational audienceNumerical simulations of Sequences of Earthquakes and Aseismic Slip (SEAS) have rapidly progressed to address fundamental problems in fault mechanics and provide self-consistent, physics-based frameworks to interpret and predict geophysical observations across spatial and temporal scales. To advance SEAS simulations with rigor and reproducibility, we pursue community efforts to verify numerical codes in an expanding suite of benchmarks. Here we present code comparison results from a new set of quasi-dynamic benchmark problems BP6-QD-A/S/C that consider an aseismic slip transient induced by changes in pore fluid pressure consistent with fluid injection and diffusion in fault models with different treatments of fault friction. Ten modeling groups participated in problems BP6-QD-A and BP6-QD-S considering rate-and-state fault models using the aging (-A) and slip (-S) law formulations for frictional state evolution, respectively, allowing us to better understand how various computational factors across codes affect the simulated evolution of pore pressure and aseismic slip. Comparisons of problems using the aging versus slip law, and a constant friction coefficient (-C), illustrate how aseismic slip models can differ in the timing and amount of slip achieved with different treatments of fault friction given the same perturbations in pore fluid pressure. We achieve excellent quantitative agreement across participating codes, with further agreement attained by ensuring sufficiently fine time-stepping and consistent treatment of boundary conditions. Our benchmark efforts offer a community-based example to reveal sensitivities of numerical modeling results, which is essential for advancing multi-physics SEAS models to better understand and construct reliable predictive models of fault dynamics.</div
Synthèse multi-cible des systèmes de contrôle-commande à l'aide de l'approche IDM
No full textInternational audienceGRAFCET is a powerful graphical modeling language for the specification of controllers in discrete event systems. It considers hierarchical structures as well as structural and semantic constraints. In this paper, we propose to use a GRAFCET specification model in a Model Driven Engineering (MDE) approach for multi-target synthesis of embedded logic control systems based on microcontrollers. In this approach, a GRAFCET metamodel is associated with a microcontroller metamodel which characterizes the microcontroller platform features to be considered when generating code. The GRAFCET metamodel includes the modeling of expressions to facilitate model verification and an easy interpretation of Grafcet events and time constraints. Transformation rules for generation of C-programmable microcontroller code are then presented. As application, we present a platform based on Eclipse EMF, Object Constraint Language (OCL) and Acceleo code generation engine.Le GRAFCET est un puissant langage de modélisation graphique pour la spécification de contrôleurs dans des systèmes à événements discrets. Il prend en compte des structures hiérarchiques ainsi que des contraintes structurelles et sémantiques.Ici, nous proposons d'utiliser un modèle de spécification GRAFCET dans une approche d'ingénierie dirigée par les modèles (IDM) pour la synthèse multi-cible de systèmes de contrôle commande embarqués basés sur des microcontrôleurs.Dans cette approche, un métamodèle GRAFCET est associé à un métamodèle microcontrôleur, lequel caractérise les fonctionnalités de la plateforme spécifique microcontrôleur à considérer lors de la génération de code.Ce métamodèle GRAFCET proposé prend en compte la modélisation des expressions pour faciliter la vérification du modèle et une interprétation facile des événements GRAFCET ainsi que des contraintes de temps. Les règles de transformation utiles à la génération de code pour des microcontrôleurs C-programmables sont ensuite présentées.Comme application, nous présentons une plateforme basée sur Eclipse EMF, Object Constraint Language (OCL) et le moteur de génération de code Acceleo
Addressing Common Inconsistencies in Sewer Networks Data
No full textInternational audienceIn sewer networks, adding a new element involves multiple phases, including planning, installation, and ongoing maintenance. At each stage of the element's lifecycle-whether it is a pipe, a structure, or an apparatus-different stakeholders and experts are involved. Due to variations in data practices, maintaining accurate and standardized data becomes a significant challenge. However, managing these networks requires consistent and reliable data to ensure effective decision-making and operational efficiency.These imperfections can stem from various reasons, including discrepancies in data collection methods, outdated or incomplete documentation, and human errors during data entry. Additionally, the integration of data from diverse sources, such as GIS systems, maintenance reports, and sensor networks, often lead to inconsistencies and redundancies, complicating data processing and analysis.For large datasets, which are common in sewer networks, it becomes increasingly difficult to identify and address inconsistencies. To address this, we built an Ontology-Based Data Access (OBDA) system which provides a unified semantic view of the data facilitating data access and integration. The system consists of a conceptual layer that provides the controlled vocabulary of sewer networks, a data layer where Montpellier Metropole open data is stored in relational databases, and a mapping layer between the two. Through this framework, common inconsistencies were identified such as missing node connections, duplicate entries, and conflicting attribute values for a specific dataset
Unexpected pampatheriid from the early Oligocene of Peruvian Amazonia: insights into the tropical differentiation of cingulate xenarthrans
No full textInternational audienceCingulates (armoured xenarthrans) constitute one of the most peculiar endemic clades of South American mammals. Their first occurrence in the fossil record can be traced back to the early Eocene. However, their Palaeogene remains are scarce, especially in tropical regions. Here, we report an isolated molariform tooth of xenarthran from the early Oligocene of Peruvian Amazonia. This tooth is small and bilobed, with slightly marked apicobasal sulci, more compatible with a cingulate dental pattern than that of folivorans (the only toothed pilosans). High-resolution microtomography of this specimen reveals an inner layer highly vascularised suggestive of osteodentine, encircled by a middle layer of orthodentine with densely S-curved dentinal tubules, and a thin outer layer. There is no clear evidence regarding the presence of cement, otherwise typically present in tree sloths. Although its external appearance cannot fully discard an assignment to a sloth, the microstructural pattern, such as well-developed osteodentine arranged in a row without ramifications, suggests that this tooth belongs to an early pampatheriid. The presence of Oligocene Pampatheriidae in Western Amazonia, previously suggested by isolated osteoderms, is substantiated by this dental remain, which underlines the importance of tropical areas for the differentiation of cingulate xenarthrans
Records of Ground Deformation in Northern Kefalonia Inferred from Cosmogenic 36Cl Geochronology
No full textInternational audienceThis study presents the first direct cosmogenic 36Cl-based chronology of landscape evolution and ground deformation in the Ionian Islands, focusing on the Thinia Valley in northern Kefalonia, western Greece. At the Zola site, exposure ages indicate that the eastern limb of the associated anticline has undergone intermittent deformation since at least 34 ka, with ongoing exhumation still occurring today. Variability in erosion rates suggests a complex deformation history, with lower-elevation samples exhuming faster than those at higher elevations. The findings highlight the role of progressive landslide activity rather than a single catastrophic failure. The compression-induced asymmetry of the Zola anticline, along with regional seismicity, appears to control slope instability. The exposure ages at the SK site reveal a surface that reached steady-state long before 20 ka, with a uniform erosion rate of 47.72 ± 0.82 m·Ma−1, consistent with regional estimates. Additionally, a prehistoric earthquake—dated at 4.8 ± 0.14 ka—has been identified, with a planar surface exhumed in a single slip event. These findings emphasize the tectonic mobility of the region, with deformation processes persisting since the Middle Pleistocene. The results contribute to a broader understanding of fault-controlled slope instability and have direct implications for seismic hazard assessment in actively deforming terrains
Evidence for Pathogen‐Driven Selection Acting on <i>HLA‐DPB1</i> in Response to <i>Plasmodium falciparum</i> Malaria in West Africa
No full textData Availability Statement: Raw sequence data, individual genotypes and related metadata are available on the public FAIR repository yareta.unige.ch (https://doi.org/10.26037/yareta:3hafz2shyjfoterxpxrbh6htgq) and scripts on gitlab.unige.ch (https://gitlab.unige.ch/asm-laboratory/DPB1-malaria).International audienceAfrican populations remain underrepresented in studies of human genetic diversity, despite a growing interest in understanding how they have adapted to the diverse environments they live in. In particular, understanding the genetic basis of immune adaptation to pathogens is of paramount importance in a continent such as Africa, where the burden of infectious diseases is a major public health challenge. In this study, we investigated the molecular variation of four Human Leukocyte Antigens (HLA) class II genes (DRB1, DQA1, DQB1 and DPB1), directly involved in the immune response to parasitic infections, in more than 1000 individuals from 23 populations across North, East, Central and West Africa. By analyzing the HLA molecular diversity of these populations in relation to various geographical, cultural and environmental factors, we identified divergent genetic profiles for several (semi-)nomadic populations of the Sahel belt as a signature of their unique demography. In addition, we observed significant genetic structuring supporting both substantial geographic and linguistic differentiations within West Africa. Furthermore, neutrality tests suggest balancing selection has been shaping the diversity of these four HLA class II genes, which is consistent with molecular comparisons between HLA genes and their orthologs in chimpanzees (Patr). However, the most striking observation comes from linear modeling, demonstrating that the prevalence of Plasmodium falciparum, the primary pathogen of malaria in Africa, significantly explains a large proportion of the nucleotide diversity observed at the DPB1 gene. DPB1*01:01, a highly frequent allele in Burkinabé populations, is identified as a potential protective allele against malaria, suggesting that strong pathogen-driven positive selection at this gene has shaped HLA variation in Africa. Additionally, two low-frequency DRB1 alleles, DRB1*08:06 and DRB1*11:02, also show significant associations with P. falciparum prevalence, supporting resistance to malaria is determined by multigenic and/or multiallelic combinations rather than single allele effects