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Sports de nature et biodiversité en montagne - Exemple d’impacts sur les ongulés sauvages
No full textInternational audienc
Mobilisation de la connaissance, pour accompagner la transition vers des systèmes de culture gérant les adventices avec moins d'herbicides
No full textDiagnostic et conception participative de systèmes de culture - Ce volume fait suite au carrefour de l'innovation Inrae, organisé par Inrae, Agreenium et l'Institut Agro Dijon, les 26 et 27 novembre 2024 de restitution du projet sur les Connaissances et outils pour des démarches préventives et opérationnelles en gestion agroécologique des adventices (COPRAA).National audienceThis article is a testimonial from an agronomist advising farmers, describing the interactions between development and research around three themes presented at the end-of-project seminar of the Ecophyto COPRAA project: the production of knowledge on weed control, the development and use of decisionsupport tools, and the participative design of low- or no-herbicide-use systems. This testimonial shows the results of exchanges between the agronomist activity and the research activity of INRAE Dijon team. Three topics in particular are addressed: the mobilization of the product of interactions over time, the use of the FLORSYS mechanistic "virtual-field" model to assess potential changes in weed flora over time, and the design of a tool accessible to farmers through the appropriation and transfer of the knowledge provided. Finally, the article reflects on co-innovation based on the experience of the COPRAA project and highlights the implications for the actors accompanying farmers.Cet article est le témoignage d'un agronome du conseil et relate les interactions entre développement et recherche autour de trois thèmes présentés lors du séminaire de fin de projet Ecophyto COPRAA : la production de connaissances sur la régulation des adventices, le développement et l'utilisation d'outils d'aide à la décision, ainsi que la conception participative de systèmes peu ou pas consommateurs d'herbicides. Ce témoignage montre les résultats des échanges entre l'activité d'agronome de l'accompagnement et celle de recherche de l'équipe de INRAE Dijon. Trois axes sont particulièrement abordés : la mobilisation du produit des interactions dans la durée, l'utilisation du modèle mécaniste de « parcelle virtuelle » FLORSYS pour évaluer les évolutions potentielles de la flore adventice dans le temps, et la conception d'un outil accessible pour les agriculteurs grâce à l'appropriation des connaissances fournies et leur transfert. Enfin, l'article propose une réflexion sur la co-innovation, à partir de l'expérience vécue lors du projet COPRAA et met en avant les implications pour les acteurs accompagnant les agriculteurs
Spatio-temporal surveys of the brown meagre Sciaena umbra using passive acoustics for management and conservation
No full textConservation of exploited fish populations is a priority for environmental managers. Spatio-temporal knowledge on reproductive sites is mandatory for species and habitat conservation but is often difficult to assess, particularly over vast geographic areas. Regular and long-term standardized surveys are necessary to identify reproductive sites, assess population trends and their distribution. Here we emphasize the utility of Passive Acoustic Monitoring (PAM) for the survey and management of a depleted vulnerable Mediterranean fish species, the brown meagre, Sciaena umbra . Acoustic surveys of reproductive calls were conducted combining 1) spatial data from standardized surveys within three MPAs and from 49 unprotected sites throughout the Northwestern Mediterranean basin, as well as 2) temporal data from a two-year-long survey at a presumed spawning location. The MPA surveys, which rapidly scanned ~30-50 km of the rocky coastlines per MPA, unveiled maps of distribution and reproductive activity of the brown meagre, including potential spawning sites. They were also effective in emphasizing effects linked to management actions: Full-protection zones had a higher number of vocalizations (70% of the listening sites) compared to less protected zones (30% of the sites) or sites outside MPAs (45% of the sites). This was also reflected in the number of singers that was generally low (< 3 individuals) in less protected zones and outside MPAs, implying lower fish densities. Highest calling aggregations were observed in potential spawning areas that represented only 0.04% of all listening sites, and were almost all in older, fully protected MPAs, which thus play a key role for fish stock recovery. The two-year survey revealed a 5-month reproductive season (from May to October) with a strong positive correlation between calling activity and temperature. Overall this study confirms the role of PAM as an efficient, replicable and standardized non-invasive method for population management that can identify functional sites and key protection zones, provide valuable information on reproduction, spatial and temporal occurrence, but also on population trends and climate-driven changes. Highlights Monitoring of threatened species and their key habitats is critical for environmental managers. Management requires methods to assess population trends at large spatial and temporal scales. Passive acoustics (PA) is efficient in mapping and monitoring vulnerable fish species. Distribution, reproductive sites and population dynamics can be assessed over vast geographical areas. We show the utility of PA to identify key conservation zones and assess effects of management actions
Référentiel des séquences génétiques des espèces de France : note pour la mise en place d'un nouvel outil national
No full textThe repository, which is the subject of this document, is a new national tool providing genetic sequences to:- Improve and objectify the reliability of taxonomic assignments derived from analyses of environmental samples or specimens using molecular techniques;- Improve the quality of occurrence data derived from molecular analyses of species present in French territories, and facilitate access, interoperability and reuse;- Pool efforts to construction, maintenance, and updating of reference sequence baseline by offering a public and shared reference systemCoordinated by PatriNat in collaboration with a scientific consortium that contributed to its construction and validation, the main aims of this document are to:1. Identify and characterize the needs and issues relating to the creation of a repository of genetic sequences under the Biodiversity Information System (BIS), by involving the stakeholders, including the National Museum of Natural History,2. Assess existing systems that could contribute to the creation of this repository,3. Propose a prefiguration of the genetic sequence repository through :- A list of quality criteria to be taken into account,- A taxonomic scope, a genetic scope and standards to be used,- Prefiguration of the repository architecture diagram,- Governance of the repository.While the priority groups are those targeted by public policies, the repository concerns eukaryotic species (Hexagon, Corsica and Overseas) present or having been present on national territory (native and introduced species) and species not present in France but for which France is setting up a specific monitoring system. The creation of this national repository thus represents a key issue for biodiversity inventory, monitoring and surveillance, and ultimately for biodiversity conservation.Le référentiel, dont il est question dans ce document, est un nouvel outil national mettant à disposition des séquences génétiques pour : • Améliorer et objectiver la fiabilité des assignations taxonomiques dérivées des analyses d’échantillons environnementaux ou de spécimens par des techniques moléculaires ;• Améliorer la qualité des données d’occurrence provenant d’analyses moléculaires portant sur les espèces présentes dans les territoires français, en faciliter l’accès, l'interopérabilité et leur réutilisation ;• Mutualiser les efforts de construction, de maintenance et d’alimentation des bases de séquences de référence, en proposant un référentiel public et partagé.Coordonné par PatriNat en collaboration avec un consortium scientifique qui a contribué à sa construction et sa validation, ce document a pour objectifs principaux de :1. Identifier et caractériser les besoins et les enjeux relatifs à la création d’un référentiel de séquences génétiques relevant du système d’information sur la biodiversité (SIB), en associant les parties prenantes, dont le Muséum national d’Histoire naturelle,2. Faire un état des lieux des dispositifs existants pouvant contribuer à la constitution de ce référentiel,3.Proposer une préfiguration du référentiel de séquences génétiques à travers :• Une liste de critères de qualité à prendre en compte,• Un périmètre taxonomique et un périmètre génétique et des standards sur lesquels s’appuyer,• Une préfiguration du schéma de l’architecture du référentiel,• Une gouvernance du référentiel.Si les groupes prioritaires sont ceux ciblés par des politiques publiques, le référentiel concerne les espèces Eucaryotes (Hexagone, Corse et Outre-mer) présentes ou ayant été présentes sur le territoire national (natives et introduites) et les espèces non présentes en France mais pour lesquelles la France met en place un dispositif spécifique de surveillance. La création de ce référentiel national représente ainsi un enjeu pour l’inventaire, le suivi et la surveillance de la biodiversité et in fine pour la conservation de la biodiversité
V-Mango, a functional-structural plant model of mango tree growth, development and fruit production: from model design to applications
No full textProceedings of the XIII International Mango Symposium, 2023-09-29/2023-10-03, Malaga, Spain.International audienceMango (Mangifera indica L.) is the fifth most produced fruit in the world, mainly in tropical and subtropical regions. Its cultivation raises a number of issues such as low yield, irregular fruit production across years, phenological asynchronisms resulting in long periods of susceptibility to pests and diseases, and heterogeneity of fruit quality at harvest. To address these issues, a functional-structural plant model, V-Mango, has been developed and implemented in the ‘vmango-lab’ virtual modelling environment. V-Mango has two objectives: to improve our understanding of tree functioning, and to assist in the design of sustainable mango production systems. V-Mango, developed for the cultivar ‘Cogshall’ in Réunion Island, is structured with modules representing interrelated processes of architectural development and fruit growth. Appearance of growth units and inflorescences was decomposed into elementary stochastic events conditioned by structural and temporal architectural factors. Daily growth and phenology of growth units and inflorescences were modelled using empirical distributions and thermal time. Fruit growth was determined by carbon- and water-related processes modeled at the fruiting branch scale and affected by climatic variables and source–sink relationships. Currently, V-Mango allows the simulation and interactive 3D visualization of vegetative and reproductive development of unpruned mango trees, over one or successive growing cycles, on simulated or empirical architectures. Integration into the model of other important processes (e.g., pest damages, leaf senescence, mortality of growth units, light interception, light-related photomorphogenesis) is underway, as well as the effects of pruning on vegetative and reproductive development. In this way, V-Mango will better account for and simulate the effects of cultivation practices and pests on fruit production. These advances will enable the design of simulation-based management solutions to improve mango production
An evaluation of artificial floating littoral zones to support fish communities in reservoirs
No full textInternational audienceArtificial water level fluctuations (WLF) in reservoirs impact fish communities by degrading littoral habitats. To mitigate these negative effects, artificial floating islands that mimic natural littoral zones appear as a promising mitigation tool. However, their effectiveness in supporting fish communities remains poorly documented. In this study, three artificial floating littoral zones (FLOLIZ, 70 m 2 surface area) were installed in a French hydropower reservoir subject to extreme WLF. Fish communities were assessed in spring and summer over four years in FLOLIZ and in control littoral stations during daytime and nighttime. Fish, especially juveniles, did not appear more frequently in FLOLIZ than in control littoral stations during daytime. At night, both adult and juvenile fish were more abundant in the littoral zone of the reservoir. During the day, the fish community in FLOLIZ was mainly composed of juvenile Chondrostoma toxostoma and adult Perca fluviatilis. Differences occurred only for a few species and life stages (juvenile vs adult); however, in general, results indicated greater abundance or richness in control littoral stations. These results do not support the effectiveness of FLOLIZ in mitigating deleterious effects of artificial WFL. The distance of FLOLIZ to the littoral zone could explain these results. Further studies in different environmental conditions, in different ecosystems and with different FLOLIZ designs are needed to provide additional information on the effectiveness of such structures as a mitigation tool
Can we count you: validating density estimation methods for unmarked wildlife with camera traps
No full textInternational audienceEstimating population densities of large wildlife in forests has traditionally relied on either spatial capture-recapture (SCR) for animals that are individually marked, or line transect distance sampling (LTDS) for species observable by researchers. Recent advances have now introduced more general camera trap models that are applicable to a large range of terrestrial medium to large-sized species. However, validation of these unmarked density (UD) models remains scarce due to the lack of available density estimates that can serve as references. We tested the accuracy and precision of three UD models (the random encounter model, camera trap distance sampling, and the time-to-event model) against independent SCR estimates for ocelots and jaguars, and against LTDS estimates for eight unmarked species varying in abundance and ecology. We found that UD model estimates for ocelots were relatively accurate in matching the estimates from SCR, albeit with less precision. Additionally, UD model estimates were similar to LTDS estimates for seven out of eight studied species. Estimates for jaguar were, however, not similar between UD models and SCR, implying that UD models are not useful for rare species. Overall, our findings show that UD models are promising tools for monitoring abundant to relatively rare unmarked species in forests, although SCR remains preferred for marked species. To ultimately aid conservationists in making informed conservation decisions, efforts should be directed towards enhancing the precision of these models as well as their ease of access for nontechnical practitioners
Unraveling Lake Geneva's hypoxia crisis in the Anthropocene
No full textInternational audienceRecent decades have witnessed widespread deoxygenation of temperate lakes. The intricate interplay between climate change and nutrient loading and its impact on oxygen dynamics still lacks clear understanding. We develop a paleo-data-model coupling approach to investigate long-term variations of dissolved oxygen conditions in Lake Geneva over the period 1850-2100. Our approach provides first estimates of oxygen baseline conditions and quantifies duration of hypoxia since pre-disturbance. Over the 19 th and 20 th centuries, an increase in DO consumption rates (from 0.3 to 2.5 g O 2 m À2 d À1 ) following nutrient over-enrichment caused the onset of hypoxia, and its intensity and duration were governed by the combined influence of climatic forcing and high phosphorus concentration. In the future, hypoxia will be primarily disrupted by reduced frequency of full mixing events
Relevés et observations hydromorphologiques sur les zones amont de cours d'eau. Protocole ROHZACE
No full textLe protocole ROHZACE a été élaboré pour décrire les caractéristiques hydromorphologiques des cours d’eau situés en têtes de bassin versant. Il a été conçu dans le cadre du projet OFB « Caractérisation des têtes de bassins versants » (phase 1 - 2024-2026), afin d’améliorer les connaissances sur les cours d’eau en conditions de référence, peu ou pas impactés par les activités anthropiques. Ce protocole peut toutefois également être mis en œuvre sur des cours d’eau altérés ou restaurés. Le protocole a été développé plus spécifiquement pour l’étude des petits cours d’eau (rangs de Strahler 1 et 2 à l’échelle 1 : 25 000e), prospectables à pied. Il s’appuie sur la mesure et la collecte de données de terrain et vise à renseigner, à l’échelle stationnelle, les principales caractéristiques 1) du lit mineur (géométrie, pente et sinuosité du lit, granulométrie, description des berges, des faciès d’écoulement et du colmatage, habitats aquatiques) et 2) de la bande rivulaire et du lit majeur. Le protocole a été développé pour pouvoir appréhender les spécificités (dimensions, accessibilité, isolement) des cours d’eau en têtes de bassin versant dans toute leur diversité. Le protocole ROHZACE pourra faire l’objet d’ajustements ou de compléments au gré des futures mises en œuvre et retours d’expériences
Normano-Breton Gulf ISRA
No full textThis factsheet has undergone review by the ISRA Independent Review Panel prior to its publicationNormano-Breton Gulf is located in northern France and the eastern Channel Islands of the United Kingdom of Great Britain and Northern Ireland. This area is shallow and is influenced by a large tidal amplitude and strong tidal currents. The habitat is mainly characterised by soft substrates of sandy-mud and coarse sediments, and by rocky plateaus and reefs. The area overlaps with the Les Écréhous & Les Dirouilles, Jersey Ramsar Site. Within this area there are: reproductive areas (e.g., Blonde Skate Raja brachyura)