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International audience; Context : Flower-visiting insects depend on floral resource availability from both cultivated and semi-natural habitats in agricultural landscapes. Landscape studies exploring insect abundance mainly focus on land cover maps without considering plant species within. Highlighting the functional role of landscapes through the potential floral resources they provide is an overlooked innovative approach. Objectives : We aimed to identify traits of floral communities that are important, across several spatial scales, for explaining the abundance of flower-visiting insects. Mapping and quantifying potential floral resources according to their attractivity, accessibility and profitability in both crop and non-crop habitats was performed to gain insights into flower-vising insect requirements. Methods : We translated land-cover maps of 39 landscapes of 250 m, 500 m and 1000 m radius into potential floral resource maps, using pre-existing vegetation surveys and floral traits databases. In the centres of the landscapes, the abundance of flower-visiting insect groups (domestic and wild bees, bumblebees and hoverflies) were recorded in organic winter cereal fields. We then fitted Generalized Linear Models (GLMs) to investigate the effects of flower trait variables (pre-selected with conditional random forests) at both field and landscape scales on the abundance of each flower-visiting insect group. Results : Floral resource maps explained the abundances of flower-visiting insect groups. Small wild bees (< 1 cm) responded positively to the relative amount of attractive and accessible floral resources at 250 m. The abundance of domestic bees and bumblebees was positively correlated with the relative amount of high nectar producing plants at 1000 m. The abundance of hoverflies was positively influenced by the relative amount of actinomorphic flowers (i.e., those with radial symmetry), at 1000 m.Conclusion : Resource maps could explain flower-visiting insect abundances, identify which category of floral resources organisms require, and determine in which habitat types these resources prevail. These results open a new research area related to managing the environment by optimising floral resources for flower-visiting insect conservation and pollination maintenance.

We are in a climate and ecological emergency, where climate change and direct anthropogenic interference with the biosphere are risking abrupt and/or irreversible changes that threaten our life-support systems. Efforts are underway to increase the resilience of some ecosystems that are under threat, yet collective awareness and action are modest at best. Here, we highlight the potential for a biosphere resilience sensing system to make it easier to see where things are going wrong, and to see whether deliberate efforts to make things better are working. We focus on global resilience sensing of the terrestrial biosphere at high spatial and temporal resolution through satellite remote sensing, utilizing the generic mathematical behaviour of complex systems—loss of resilience corresponds to slower recovery from perturbations, gain of resilience equates to faster recovery. We consider what subset of biosphere resilience remote sensing can monitor, critically reviewing existing studies. Then we present illustrative, global results for vegetation resilience and trends in resilience over the last 20 years, from both satellite data and model simulations. We close by discussing how resilience sensing nested across global, biome-ecoregion, and local ecosystem scales could aid management and governance at these different scales, and identify priorities for further work. This article is part of the theme issue ‘Ecological complexity and the biosphere: the next 30 years’.

The full dataset is freely available at the link below (perennial repository) for academic use or other non-commercial use: https://lab.plantnet.org/seafile/d/936fe4298a5a4f4c8dbd/; The difficulty to measure or predict species community composition at fine spatio-temporal resolution and over large spatial scales severely hampers our ability to understand species assemblages and take appropriate conservation measures. Despite the progress in species distribution modeling (SDM) over the past decades, SDM are just beginning to integrate high resolution remote sensing data and their predictions are still entailed by the many biases and heterogeneous quality of the available biodiversity observations, most often opportunistic presence only data. We designed a European scale dataset covering around 10K plant species to calibrate and evaluate SDM predictions of species composition in space and time at high spatial resolution (~10m), and study their spatial transferability. For model training, we extracted and harmonized 5 million heterogeneous presence-only observations from selected GBIF datasets and 5 thousand exhaustive presence-absence surveys both sampled during the 2017-2021. We associated them to various environmental rasters classically used in SDMs, as well as to 10x10m resolution RGB and Near-Infra-Red satellite images and 20 years-time series of climatic variables and satellite point values. The evaluation dataset is based on 20K standardized presence-absence surveys separated from the training set with a spatial block hold out procedure. The GeoLifeCLEF 2023 dataset is open access and the first benchmark for researchers aiming to improve the prediction of plant species composition at a very fine spatial grain and at continental scale. It is also a space to explore new ways of combining massive and diverse species observations with environmental information at various scales. Innovative AI-based approaches, in particular, should be among the most interesting methods to experiment with on the GeoLifeCLEF 2023 dataset.

The full dataset is freely available at the link below (perennial repository) for academic use or other non-commercial use: https://lab.plantnet.org/seafile/d/936fe4298a5a4f4c8dbd/; The difficulty to measure or predict species community composition at fine spatio-temporal resolution and over large spatial scales severely hampers our ability to understand species assemblages and take appropriate conservation measures. Despite the progress in species distribution modeling (SDM) over the past decades, SDM are just beginning to integrate high resolution remote sensing data and their predictions are still entailed by the many biases and heterogeneous quality of the available biodiversity observations, most often opportunistic presence only data. We designed a European scale dataset covering around 10K plant species to calibrate and evaluate SDM predictions of species composition in space and time at high spatial resolution (~10m), and study their spatial transferability. For model training, we extracted and harmonized 5 million heterogeneous presence-only observations from selected GBIF datasets and 5 thousand exhaustive presence-absence surveys both sampled during the 2017-2021. We associated them to various environmental rasters classically used in SDMs, as well as to 10x10m resolution RGB and Near-Infra-Red satellite images and 20 years-time series of climatic variables and satellite point values. The evaluation dataset is based on 20K standardized presence-absence surveys separated from the training set with a spatial block hold out procedure. The GeoLifeCLEF 2023 dataset is open access and the first benchmark for researchers aiming to improve the prediction of plant species composition at a very fine spatial grain and at continental scale. It is also a space to explore new ways of combining massive and diverse species observations with environmental information at various scales. Innovative AI-based approaches, in particular, should be among the most interesting methods to experiment with on the GeoLifeCLEF 2023 dataset.

International audience; Since 2008, there has been a major decrease in the numbers of old and large sardines in the Gulf of Lions, which has had a major effect on regional fisheries. A bottom-up process involving a shift in diet towards smaller planktonic prey has been suggested as the main driver of this development. Yet, the reproductive capacities of the sardines have not changed, suggesting potential modifications in energy allocation trade-offs. Whether this could also affect maintenance, in particular at the end of the winter reproductive period, and explain the lower adult survival and the disappearance of older individuals remains unclear. We therefore experimentally investigated the consequences of seasonal food availability (summer vs. winter) on life-history traits and energy allocation trade-offs at the individual and population levels. Our results indicate that food resources during summer had a major effect on energy reserves and growth, limiting the maximum size and body condition reached at the end of reproduction. In addition, food restrictions during growth and/or reproduction periods led to physiological costs mediated by increased oxidative damage. Mediterranean sardines did not show any ability for compensatory growth and did not appear to be capital breeders. Instead, they displayed individual differences in coping with physiological constraints and displayed various life-history strategies regardless of food availability. We highlighted 3 main individual energy allocation strategies: (1) preferential allocation to body condition or (2) to growth, or (3) simultaneous allocation to reproduction and growth. These issues are key, as climate change is expected to favour smaller phytoplankton, which might amplify the deterioration in the condition of pelagic fish.

Contemporary climate change affects population dynamics, but its influence varies with landscape structure. It is still unclear whether landscape fragmentation buffers or amplifies the effects of climate on population size and the age and body size of individuals composing these populations. This study aims to investigate the impacts of warm climates on lizard life-history traits and population dynamics in habitats that vary in their connectivity. We monitored common lizard Zootoca vivipara populations for 3 years in an experimental system in which both climatic conditions and connectivity among habitats were simultaneously manipulated. We considered two climatic treatments (i.e. present-day climate and warm climate [+1.4°C than present-day climate]) and two connectivity treatments (i.e. a connected treatment in which individuals could move from one climate to the other and an isolated treatment in which movement between climates was not possible). We monitored survival, reproduction, growth, dispersal, age and body size of each individual in the system as well as population density through time. We found that the influence of warm climates on life-history traits and population dynamics depended on connectivity among thermal habitats. Populations in warm climates were (i) composed of younger individuals only when isolated; (ii) larger in population size only in connected habitats and (iii) composed of larger age-specific individuals independently of the landscape configuration. The connectivity among habitats altered population responses to climate warming likely through asymmetries in the flow and phenotype of dispersers between thermal habitats. Our results demonstrate that landscape fragmentation can drastically change the dynamics and persistence of populations facing climate change.Le changement climatique actuel impacte la dynamique des populations, mais son influence varie avec la structure du paysage. A ce jour, il est difficile de prédire si la fragmentation du paysage réduit ou augmente les effets du réchauffement climatique sur la taille des populations, ainsi que sur l'âge et la taille corporelle des individus qui composent ces populations. Cette étude s'intéresse aux impacts d'un climat plus chaud sur les traits d'histoire de vie et la dynamique de populations vivant dans des habitats qui diffèrent quant à leur niveau de connectivité. Pendant trois ans, nous avons suivi des populations de lézards vivipares Zootoca vivipara au sein d'un dispositif expérimental qui permet de manipuler simultanément les conditions climatiques et le niveau de connectivité entre habitats. Nous avons considéré deux traitements climatiques [i.e., climat actuel et climat chaud (+1.4°C plus chaud que le climat actuel)] et deux traitements de connectivité (i.e., un traitement connecté au sein duquel les individus pouvaient se déplacer d'un climat à un autre, et un traitement isolé au sein duquel les déplacements entre climats n'étaient pas permis). Tout au long de l'expérience, nous avons mesuré la survie, la reproduction, la croissance, la dispersion, l'âge et la taille corporelle de chaque individu ainsi que la densité des populations. Nous avons observé que l'influence du climat chaud sur les traits d'histoire de vie et la dynamique de population dépendait du niveau de connectivité entre habitats. Les populations en climat chaud étaient composées (i) d'individus plus jeunes seulement en habitat isolé, (ii) de plus d'individus uniquement en habitat connecté et (iii) d'individus plus grands à âge égal et ce indépendamment de la configuration du paysage. Nos résultats montrent que le niveau de connectivité entre habitats altère les réponses des populations au réchauffement climatique via une asymétrie dans le flux et le phénotype des dispersants entre climats. Nos résultats démontrent que la fragmentation du paysage peut influencer de façon drastique la dynamique et la persistance des populations face au changement climatique.

Peri-urban areas support a broad range of multifunctional demands for public goods. In northwest Europe, peri-urban areas tend to overlap with intensive agricultural land, resulting in conflicts between agricultural use and the public good demands of residents. Sustainable intensification (SI) of agriculture might help reconcile agricultural and well-being goals, but it is unclear how the mix of actors in a peri-urban setting can trigger or restrain SI. In a Dutch case study, we explored how SI of agriculture can contribute to making peri-urban areas more sustainable, and which actors are key enabling factors for implementing SI. We used interviews, surveys, workshops, and empirical analysis to obtain insight into the stakeholder’s vision of a sustainable future for the case study area, the farming system and actor network. We integrated these insights in a Bayesian Belief Network, where we linked the actor network to implementation of three SI measures (farm-level efficiency measures, small landscape elements, and direct sales), and used sensitivity analysis to model effects of support for implementation by different groups of actors. The case study has a dense stakeholder network, where, dependent on the SI measure, farmers are triggered by all actors to implement SI, or have a stronger role in uptake themselves. The sensitivity analysis suggested that the future preferred by the stakeholders requires broad support of all actors involved, with local actors without a formal role being essential for uptake. Overall, trade-offs among public goods are almost inevitable when taking up SI measures.

International audience; Humans have built ports on all the coasts of the world, allowing people to travel, exploit the sea, and develop trade. The proliferation of these artificial habitats and the associated maritime traffic are not predicted to fade in the coming decades. Ports share common characteristics: species find themselves in novel singular environments, with particular abiotic properties-e.g., pollutants, shading, protection from wave action-within novel communities in a melting-pot of invasive and native taxa. Here we discuss how this drives evolution, including setting-up of new connectivity hubs and gateways, adaptive responses to exposure to new chemicals or new biotic communities, and hybridization between lineages that would have never come into contact naturally. There are still important knowledge gaps however, such as the lack of experimental tests to distinguish adaptation from acclimation processes, the lack of studies to understand the putative threats of port lineages to natural populations, or to better understand the outcomes and fitness effects of anthropogenic hybridization. We thus call for further research examining "biological portuarization", defined as the repeated evolution of marine species in port-ecosystems under human-altered selective pressures. Furthermore, we argue that ports act as giant mesocosms often isolated from the open sea by seawalls and locks, and so provide replicated life-size evolutionary experiments essential to support predictive evolutionary sciences.

Forest ecosystems depend on their capacity to withstand and recover from natural and anthropogenic perturbations (that is, their resilience)1. Experimental evidence of sudden increases in tree mortality is raising concerns about variation in forest resilience2, yet little is known about how it is evolving in response to climate change. Here we integrate satellite-based vegetation indices with machine learning to show how forest resilience, quantified in terms of critical slowing down indicators3–5, has changed during the period 2000–2020. We show that tropical, arid and temperate forests are experiencing a significant decline in resilience, probably related to increased water limitations and climate variability. By contrast, boreal forests show divergent local patterns with an average increasing trend in resilience, probably benefiting from warming and CO2 fertilization, which may outweigh the adverse effects of climate change. These patterns emerge consistently in both managed and intact forests, corroborating the existence of common large-scale climate drivers. Reductions in resilience are statistically linked to abrupt declines in forest primary productivity, occurring in response to slow drifting towards a critical resilience threshold. Approximately 23% of intact undisturbed forests, corresponding to 3.32 Pg C of gross primary productivity, have already reached a critical threshold and are experiencing a further degradation in resilience. Together, these signals reveal a widespread decline in the capacity of forests to withstand perturbation that should be accounted for in the design of land-based mitigation and adaptation plans.

International audience; Freshwater fish ponds are agro-ecosystems that provide important ecosystem services (ES) to territories, notably by hosting a recognized biodiversity. In France, the low profitability of freshwater ponds for fish production runs the risk that they will be abandoned, and thus that the ES they provide will disappear. The FEAMP SEPURE project brings together scientists from different backgrounds (agronomy, ecology, biology, modelling, environmental sciences) to link farmers' practices, economic and environmental performances and pond responses by monitoring water quality, phytoplankton, zooplankton, benthic macroinvertebrates, aquatic macrophytes and fish communities. Based on the analysis of the contexts and expectations expressed in Dombes, Lorraine and Brenne-Sologne, eleven scenarios with different species assemblages were co-designed with fish farmers. They took into account many parameters, such as the complementarity of species according to their trophic and behavioral traits, water availability, water temperature in summer, the existence of local and national markets, the presence of submerged vegetation, the depth of the ponds, feeding and liming practices, and the use of the ponds for other activities (e.g. hunting). In 10 production sites, farmers applied these scenarios, and practices and ecosystems were monitored. The new data generated by the SEPURE project should help support decision making for the future development of the pond sector and help maintain this economic activity in the territories.

All data & code generated during this study have been deposited in the INRAE dataverse: https://entrepot.recherche.data.gouv.fr/dataset.xhtml?persistentId=doi:10.57745/G4D3PG. The shiny application enabling the exploration and analysis of our complete dataset (PCA, GLM/Elastic Net and associated visualizations) is available here: https://fruitfliesmetabo.shinyapps.io/shiny.; International audience; Most phytophagous insect species exhibit a limited diet breadth and specialize on a few or a single host plant. In contrast, some species display a remarkably large diet breadth, with host plants spanning several families and many species. It is unclear, however, whether this phylogenetic generalism is supported by a generic metabolic use of common host chemical compounds ('metabolic generalism') or alternatively by distinct uses of diet-specific compounds ('multi-host metabolic specialism')? Here, we simultaneously investigated the metabolomes of fruit diets and of individuals of a generalist phytophagous species, Drosophila suzukii, that developed on them. The direct comparison of metabolomes of diets and consumers enabled us to disentangle the metabolic fate of common and rarer dietary compounds. We showed that the consumption of biochemically dissimilar diets resulted in a canalized, generic response from generalist individuals, consistent with the metabolic generalism hypothesis. We also showed that many diet-specific metabolites, such as those related to the particular color, odor, or taste of diets, were not metabolized, and rather accumulated in consumer individuals, even when probably detrimental to fitness. As a result, while individuals were mostly similar across diets, the detection of their particular diet was straightforward. Our study thus supports the view that dietary generalism may emerge from a passive, opportunistic use of various resources, contrary to more widespread views of an active role of adaptation in this process. Such a passive stance towards dietary chemicals, probably costly in the short term, might favor the later evolution of new diet specializations.

International audience

International audience

Accurate streamflow forecasting can help minimizing the negative impacts of hydrological events such as floods and droughts. To address this challenge, we explore here artificial neural networks models (ANNs) for streamflow forecasting. These models, which have been proven successful in other fields, may offer improved accuracy and efficiency compared to traditional conceptually-based forecasting approaches.The goal of this study is to compare the performance of a traditional conceptual rainfall-runoff (hydrological) model with an artificial neural network (ANN) model for streamflow forecasting. As a test case, we use the Severn catchment in the United Kingdom. The adopted ANN model has a long short-term memory (LSTM) architecture with two hidden layers, each with 256 neurons. The model is trained on a 25-year dataset from 1988 to 2013 and tested on a 3-year dataset (from 2014 to 2016). It is also validated on a 3-year dataset (from 2017 to 2020, 2019 being a particularly wet year), to assess its performance in extreme hydrological conditions. The study focuses on daily and hourly predictions.To conduct this study, the conceptual hydrological model called Superflex is used as a benchmark. Both models are first evaluated using the Nash-Sutcliffe Efficiency (NSE) score. To enable a fair and accurate comparison, both models share the same inputs (i.e. meteorological forcings: total precipitation, daily maximum and minimum temperatures, daylight duration, mean surface downward short wave radiation flux, and vapor pressure). The ANN model was implemented using the Neuralhydrology library developed by F. Kratzert.In our study, we found that LSTM model is able to provide more accurate one-day forecasts than the hydrological model Superflex. For the daily predictions, the average NSE score using the LSTM model is 0.85 (with an average NSE score of 0.99 for training period, and 0.85 for validation period), which is higher than the NSE score of 0.74 achieved by the Superflex model (with a score of 0.84 for training period).The hourly prediction using NSE with the superflex model had a score of 0.88, with a score of 0.7 during training. The LSTM model had an average NSE score of 0.87, with an average score of 0.99 during training and an average score of 0.85 during validation.These results were obtained without adjusting the hyperparameters and by training the model only on data from the Severn watershed.The ANN model has demonstrated promising results compared to a state-of-the-art conceptual hydrological model in our studies. We will further compare both models using different training dataset periods, and different catchements. These additional tests will provide more information on the capabilities of the LSTM model and help to confirm its effectiveness.

International audience; La notion d’environnement nocturne émerge à la suite de la requalification de la lumière artificielle nocturne en pollution lumineuse. Elle entend caractériser les systèmes humains et non humains fonctionnellement liés à l’obscurité. Contrairement à la notion de pollution lumineuse, elle oblige à penser conjointement les multiples enjeux du couple lumière artificielle/obscurité. En l’inscrivant dans le cadre d’analyse des systèmes socio-écologiques, nous faisons de l’environnement nocturne un objet de recherche à part entière apte à structurer une interdisciplinarité entre sciences de la nature et sciences humaines et sociales. C’est sur le territoire réunionnais que nous mettons cet objet relationnel à l’épreuve du monde réel, dans une démarche transdisciplinaire menée avec une multiplicité d’acteurs autour des enjeux d’aménagement que soulève la volonté de préservation holistique de la ressource obscurité. Du savoir à l’action, de la construction d’un objet de recherche à l’installation d’un dispositif collaboratif dédié à la production de connaissances scientifiques situées sur l’environnement nocturne et à l’accompagnement des acteurs locaux dans leurs démarches de préservation et de valorisation de l’obscurité, il s’agira bien sûr de rendre compte et discuter d’un processus de recherche hybride qui puise sa vitalité dans une interdisciplinarité radicale. Mais il s’agira également de témoigner de certaines difficultés que des différences de conceptions et de pratiques professionnelles peuvent poser dans la symétrisation des relations entre scientifiques et non scientifiques, entre chercheurs et autres acteurs sociaux.

Determining how sibling interactions alter the fitness outcomes of dispersal is pivotal for the understanding of family living, but such studies are currently scarce. Using a large demographic dataset on pre-industrial humans from Finland, we studied dispersal consequences on different indicators of lifetime reproductive success according to sex-specific birth rank (a strong determinant of dispersal in our population). Contrary to the predictions of the leading hypotheses, we found no support for differential fitness benefits of dispersal for either males or females undergoing low vs. high sibling competition. Our results are inconsistent with both hypotheses that family members could have different fitness maximizing strategies depending on birth rank, and that dispersal could be mainly driven by indirect fitness benefits for philopatric family members. Our study stresses the need for studying the relative outcomes of dispersal at the family level in order to understand the evolution of family living and dispersal behaviour.

International audience; A large part of the soil protist diversity is missed in metabarcoding studies based on 0.25 g of soil environmental DNA (eDNA) and universal primers due to ca. 80% co-amplification of non-target plants, animals and fungi. To overcome this problem, enrichment of the substrate used for eDNA extraction is an easily implemented option but its effect has not yet been tested. In this study, we evaluated the effect of a 150 μm mesh size filtration and sedimentation method to improve the recovery of protist eDNA, while reducing the co-extraction of plant, animal and fungal eDNA, using a set of contrasted forest and alpine soils from La Réunion, Japan, Spain and Switzerland. Total eukaryotic diversity was estimated by V4 18S rRNA metabarcoding and classical amplicon sequence variant calling. A 2- to 3- fold enrichment in shelled protists (Euglyphida, Arcellinida and Chrysophyceae) was observed at the sample level with the proposed method, with, at the same time, a 2-fold depletion of Fungi and a 3- fold depletion of Embryophyceae. Protist alpha diversity was slightly lower in filtered samples due to reduced coverage in Variosea and Sarcomonadea, but significant differences were observed in only one region. Beta diversity varied mostly between regions and habitats, which explained the same proportion of variance in bulk soil and filtered samples. The increased resolution in soil protist diversity estimates provided by the filtration-sedimentation method is a strong argument in favour of including it in the standard protocol for soil protist eDNA metabarcoding studies

The uncontrolled colonization of benthic organisms on submerged surfaces, also called biofouling, causes severe damage in the shipping and aquaculture industries. Biofouling starts with a benthic biofilm composed of a complex assemblage of microbes, bacteria and benthic diatoms, called microfouling, on which macrofouling invertebrate species settle and grow. Invertebrate larvae may use natural soundscapes to orientate inshore and choose their optimal habitat. Recent studies have demonstrated that ship sounds enhance the larval settlement and growth of several invertebrate species, such as mussels, associated with biofouling. Among invertebrates, effects of sound generated by offshore human activities are still poorly studied. This study aims to assess the effect of pile driving, drilling and vessel sounds on model species associated with micro and macrofouling. First, the biofilm development of Navicula pelliculosa and Amphora coffeaeformis was assessed, then, the larval development of the blue mussel (Mytilus edulis) was evaluated from the D-veliger to the postlarval stage. Mussel larvae and microalgae were exposed 12 h each day in tanks (Larvosonic) adapted to sound experiments under controlled conditions. All anthropogenic sounds induced a thinner N. pelliculosa biofilm coupled with a lower microalgae concentration. The drilling sound had a stronger effect on the biofilm thickness. The drilling sound significantly reduced the pediveliger settlement and the postlarvae clearance rate by 70.4% and tended to diminish settler sizes compared to control sound. Contrary to our expectation, pile driving tended to enhance larval recruitment by 22% (P=0.077) and the boat sound did not stimulate larval settlements or recruitment. Drilling sound generated a stressful acoustic environment for pediveliger settlements and postlarvae seem to maintain their shell valves closed to preserve energy. We identify potential causes and mechanisms involved in these impacts of anthropophony on larval ecology and microfouling dynamics.

Plasmodium falciparum, the most virulent agent of human malaria, spread from Africa to all continents following the out-of-Africa human migrations. During the transatlantic slave trade between the 16thand 19thcenturies, it was introduced twice independently to the Americas where it adapted to new environmental conditions (new human populations and mosquito species). Here, we analyzed the genome-wide polymorphisms of 2,635 isolates across the currentP. falciparumdistribution range in Africa, Asia, Oceania, and the Americas to investigate its genetic structure, invasion history, and selective pressures associated with its adaptation to the American environment. We confirmed that American populations originated from Africa with at least two independent introductions that led to two genetically distinct clusters, one in the North (Haiti and Columbia) and one in the South (French Guiana and Brazil), and the admixed Peruvian group. Genome scans revealed recent and more ancient signals of positive selection in the American populations. Particularly, we detected positive selection signals in genes involved in interactions with host (human and mosquito) cells and in genes involved in resistance to malaria drugs in both clusters. We found that some genes were under selection in both clusters. Analyses suggested that for five genes, adaptive introgression between clusters or selection on standing variation was at the origin of this repeated evolution. This study provides new genetic evidence onP. falciparumcolonization history and on its local adaptation in the Americas.

This PhD. aims at assessing the ability of emerging fluvial remote sensing techniques (such as terrestrial and topo-bathymetric LiDAR, hyperspectral imaging, and thermal infrared imaging) to characterize and monitor fluvial corridors. The study site is the lower basin of the Ain River which is affected by a range of issues related to channel incision, and is the location of a gravel augmentation project. First, we use hyperspectral imaging to predict channel bathymetry for a reference discharge and depths up to 2.5 meters along a river reach of 20 km. This allows us to confirm the ability of hyperspectral optical models to be extrapolated to a long river reach, and to retrieve with a single campaign bathymetric data for multiple discharge conditions. We study the errors occurring along the 20 km reach and then we use the same methodology to identify morphological changes occurring between 2015 and 2022 and to therefore evaluate its applicability for change monitoring. Second, we combine forestry field surveys with LiDAR and hyperspectral data in order to characterize the riparian forest. We demonstrate the ability of such datasets to describe morphological changes along an age gradient and to predict the degree of hydrological connection of the riparian forest. Changes in the physical site conditions of the riparian forest due to channel incision leads to dryer forest conditions, and suggests the presence of potential water stress at the plot level. Third, we explore this water stress hypothesis by using thermal infrared imaging and eco-physiological field measurements. While mounting thermal infrared sensors on an airborne vector can enable water stress characterization, targeting a specific acquisition window or acquiring multiple campaigns is required to detect stress conditions due to their variability during summer. This work then allows us to make recommendations for both the management and restoration of fluvial systems and the use of remote-sensing data to characterize and monitor such environments.; Cette thèse explore le potentiel des outils émergents de télédétection fluviale (LiDAR terrestre et bathymétrique, imageur hyperspectral, imageur infra-rouge thermique) pour la caractérisation et le suivi des corridors fluviaux. Le cadre géographique d’application est la basse vallée de l’Ain, concernée par des enjeux liés à l’incision du chenal et par un projet de recharge sédimentaire. Dans un premier temps, l’imagerie hyperspectrale nous permet de restituer les profondeurs d’eau sur un linéaire de 20 kilomètres pour un débit de référence et des profondeurs allant jusqu’à 2,5 mètres. Cela nous permet de confirmer la possibilité d’extrapoler un modèle sur un long linéaire fluvial, et de restituer des profondeurs d’eau pour différents débits à partir d’une même campagne. Nous évaluons les erreurs survenant sur l’ensemble du linéaire, puis ré-exploitons les méthodes développées pour identifier les changements morphologiques survenus entre 2015 et 2022 et éprouver la robustesse de ces méthodes pour le suivi. Dans un second temps, nous couplons inventaire forestier et données LiDAR et hyperspectrales pour caractériser la forêt riveraine. Nous montrons que ces données décrivent bien les changements morphologiques des peuplements le long d’un gradient d’âge et permettent de prédire le niveau de connectivité hydrologique des ripisylves. La modification des conditions physiques des milieux forestiers entraînée par l’incision du chenal conduit à un assèchement du milieu et nous amène à identifier un stress hydrique potentiel des peuplements. Dans un troisième temps, nous explorons ce stress hydrique potentiel à partir de campagnes aéroportées d’imagerie infrarouge thermique et de relevés de terrain écophysiologiques. Bien que l’usage de caméras thermiques sur des plateformes aéroportées permette de caractériser le stress hydrique, la saisonnalité du phénomène nécessite de réaliser des acquisitions multiples ou durant une fenêtre spécifique afin de bien le détecter. L’ensemble de ces travaux nous permet de formuler des recommandations à la fois pour la gestion des milieux fluviaux et pour l’usage de données de télédétection dans les campagnes de monitoring de ces environnements.

HabRef a vocation à couvrir l'ensemble des territoires français, de métropole et d'outre‐mer et prend en compte les typologies d’habitats (dont les typologies d’habitats d’espèces) ou de végétations couvrant les milieux marins et/ou continentaux, ainsi que les listes d’habitats issues de directives communautaires ou de conventions internationales.Il est composé de deux ensembles :‐ le référentiel sensu stricto, tronc commun de champs d’informations donnant toutes les informations utiles sur chaque typologie (métadonnées) et indiquant pour chaque unité d’une typologie son identifiant unique national (CD_HAB), son nom et sa validité (nom de référence ou synonyme), son code dans la typologie, son niveau hiérarchique, sa présence en France, son descriptif principal ;‐ une base de connaissances associée au référentiel qui comporte les champs additionnels spécifiques à chaque typologie (descriptifs complémentaires, remarques, etc.) et renseigne, pour chaque unité d’une typologie, sur les relations synonymiques, la présence dans les territoiresfrançais, les liens avec les espèces, les correspondances avec d’autres unités, les sources d’information.Cette 7e version d’HabRef comporte 37 typologies et 45 tables de correspondances entre typologies, pour un total de 35 521 unités typologiques valides et de 45 782 correspondances. 99 626 relations entre unités typologiques et taxons sont également renseignées.

International audience; Tappeh Qazānchi, not far from the Razavar river, is located to the northwest of Kermanshah city at 1323 masl. Parts of the north and east sides of the mound have been damaged by agricultural activities. As a result, 100 m of the northern section has been exposed, and has been found to contain cultural sequences from throughout the Holocene. The site was sounded during the winter of 2019 to identify the cultural sequences, site formation and settlement patterns present. The extent of the core area was estimated to be ca. 2 hectares, following sounding results in test trenches that were excavated in order to define the core area and buffer zone. The first results from the stratigraphic excavation and the relative and absolute chronologies indicate that the upper levels of the site belong to the Middle Bronze Age and the Late Chalcolithic periods, and the lower levels contain a Pre-Pottery Neolithic sequence. The results of archaeobotanical, archaeozoological, micromorphological and palaeoclimatological studies point to a localised wet environment during the Holocene with periodically flooded zones around the site. Tappeh Qazānchi is comparable to the Middle Bronze Age of Chogha Maran (upper phase) and Godin Tepe (Period III), as well as the Late Chalcolithic of Siahbid (middle and late phases) and GodinTepe (Period IX), that are located in the same cultural range in Central Zagros. The Pre-Pottery Neolithic phases at Qazānchi are also contemporaneous to East Chia Sabz, Sheikh-e Abad, Kelek Asad Morad and Chogha Golan, and this is also one of the first settlements in the early Holocene in the east of the Fertile Crescent.

International audience

1. Aggregated species occurrence and abundance data from disparate sources are increasingly accessible to ecologists for the analysis of temporal trends in biodiversity. However, sampling biases relevant to any given research question are often poorly explored and infrequently reported; this can undermine statistical inference. In other disciplines, it is common for researchers to complete “risk-of-bias” assessments to expose and document the potential for biases to undermine conclusions. The huge growth in available data, and recent controversies surrounding their use to infer temporal trends, indicate that similar assessments are urgently needed in ecology. 2. We introduce ROBITT, a structured tool for assessing the “Risk-Of-Bias In studies of Temporal Trends in ecology”. ROBITT has a similar format to its counterparts in other disciplines: it comprises signalling questions designed to elicit information on the potential for bias in key study domains. In answering these, users will define study inferential goal(s) and relevant statistical target populations. This information is used to assess potential sampling biases across domains relevant to the research question (e.g. geography, taxonomy, environment), and how these vary through time. If assessments indicate biases, then usersmust clearly describe them and/or explain what mitigating action will be taken.3. Everything that users need to complete a ROBITT assessment is provided: the tool,a guidance document,and a worked example. Following other disciplines, the tool and guidance document were developed through a consensus-forming process across experts working in relevant areas of ecology and evidence synthesis.4. We propose that researchers should be strongly encouraged to include a ROBITT assessment when publishing studies of biodiversitytrends, especially when usingaggregated data. This will help researchers to structure their thinking, clearly acknowledge potential sampling issues,highlight where expert consultation is required, and provides an opportunity to describe data checks that might gounreported. ROBITT will also enable reviewers, editors, and readers to establish how well research conclusions are supported given a dataset combined with some analytical approach. In turn, itshouldstrengthen evidence-based policy and practice, reduce differing interpretations of data, and provide a clearer picture of the uncertainties associated with our understanding of reality. risk-of-bias; speciesoccurrence data; temporal trends; Essential Biodiversity Variables; indicators; uncertainty; insect declines

International audience; The Alentejo region in Portugal is vital to the country's beef industry and is home to 60% of the Portuguese beef cattle population. Farmers increasingly rely on imported synthetic fertilizer and feed. The uncertainty of global oil supply and indirect inputs calls into question the robustness of the beef farming system in Alentejo, defined as the capacity of the system to maintain its function (beef production) in spite of a disturbance (decreased input availability). An additional challenge is the need for reducing greenhouse gas emissions to meet decarbonization goals. At present, these challenges are being addressed through management practices such as expanding areas of high-yield sown biodiverse pastures and fattening steers partially on grass rather than concentrates. These practices have been shown to reduce greenhouse gas emissions, but their effect on the robustness of beef production when inputs are scarce is unknown. To fill this gap, we adapted a dynamic nitrogen mass flow model to assess herd dynamics and calculate a greenhouse gas emissions balance. We applied the model for seven scenarios corresponding to different combinations of management practices over 50 years with increasing input constraints. We estimated, without changes and without constraints, a greenhouse gas balance of 55 kgCO(2)-e kg carcass(-1) year(-1) (100-years global warming potential). Without changes but faced with constraints, meat production dropped 60% (low long-term robustness) in 50 years while increasing by 17% the greenhouse gas balance. Our results showed that a combination of high-yield legume-rich pastures, maximization of grass intake, herd size reduction, and increased animal productivity allowed the smallest reduction of meat production (28%) and largest greenhouse gas emission reduction (30%, i.e., 38.9 kgCO(2)-e kg carcass(-1) year(-1)). This was the best, among the combination studied, at mitigating the trade-off between robust meat production and climate change mitigation.

Dispersal is a ubiquitous phenomenon which affects the population dynamics and evolution of natural populations, hence it is a fundamental process in driving species persistence under global changes. However, dispersal rates and dispersal range are difficult to measure in most species, and remain unknown for many. In addition, informed behaviors, whereby individuals leave their natal area and select a breeding habitat non-randomly, may play an important role in species' responses to global change, and are even more difficult to comprehend. By developing new models combing demographic and genetic data, we reveal dispersal rates, range and behaviors for emperor penguin, a species threatened by climate change and living in the most remote place on earth where measurements of dispersal are nonexistent. We found that emperor penguins have a short distance of dispersal compared to their capacity to cover large distances during seasonal migration. On average, emigration rates are small, with emigration occurring when the local habitat becomes unsuitable (informed emigration). While overall dispersal rates remain low, occasional mass emigration events can occur in some regions. We also detect environmental and demographic drivers of emigration using new independent data:emigration is more likely to occur for habitats far from open water and with low food availability. Finally, we provided new global population forecasts for emperor penguins that incorporate dispersal processes into a sea-ice dependent demographic model that can inform conservation actions in Antarctica. Our method can be applied to other species and data-poor systems to estimate dispersal processes.

This first book volume collects country reports produced by the AE4EU Horizon 2020 project and the European Association Agroecology Europe which involved a large number of organisations, as well as more than 25 "mappers" who conducted the work in different European countries. Among them were many members of the Agroecology Europe Youth Network (AEEUYN). The different volumes of the book series offer an illustrative state of the art of agroecology in Europe by synthesizing and providing key information on the common understanding of agroecology, as well as its development at the European level. To scale up agroecology, this first book volume provides critical information and analysis of the development of agroecology in different contexts, which is very much needed as a necessary step to attain larger insights about the state of the art of agroecology, as well as to support its expansion and use at the policymaker level. Documenting the development of agroecology in 13 European countries (Albania, Austria, Bosnia, Bulgaria, Croatia, Germany, Greece, Italy, Kosovo, Malta, Montenegro, North Macedonia, and Romania), this volume describes 112 initiatives, examples, cases, and programmes linked to agroecology, and the development of agroecology in these European countries as well as the diversity of use of the concept.

International audience; Although animal dispersal is known to play key roles in ecological and evolutionary processes such as colonization, population extinction and local adaptation, little is known about its genetic basis, particularly in vertebrates. Untapping the genetic basis of dispersal should deepen our understanding of how dispersal behaviour evolves, the molecular mechanisms that regulate it and link it to other phenotypic aspects in order to form the so-called dispersal syndromes. Here, we comprehensively combined quantitative genetics, genome-wide sequencing and transcriptome sequencing to investigate the genetic basis of natal dispersal in a known ecological and evolutionary model of vertebrate dispersal: the common lizard, Zootoca vivipara. Our study supports the heritability of dispersal in semi-natural populations, with less variation attributable to maternal and natal environment effects. In addition, we found an association between natal dispersal and both variation in the carbonic anhydrase (CA10) gene, and in the expression of several genes (TGFB2, SLC6A4, NOS1) involved in central nervous system functioning. These findings suggest that neurotransmitters (serotonin and nitric oxide) are involved in the regulation of dispersal and shaping dispersal syndromes. Several genes from the circadian clock (CRY2, KCTD21) were also differentially expressed between disperser and resident lizards, supporting that the circadian rhythm, known to be involved in long-distance migration in other taxa, might affect dispersal as well. Since neuronal and circadian pathways are relatively well conserved across vertebrates, our results are likely to be generalisable, and we therefore encourage future studies to further investigate the role of these pathways in shaping dispersal in vertebrates.

International audience

International audience

The survival of animals depends, among other things, on their ability to identify threats in their surrounding environment. Senses such as olfaction, vision and taste play an essential role in sampling their living environment, including microorganisms, some of which are potentially pathogenic. This study focuses on the mechanisms of detection of bacteria by theDrosophilagustatory system. We demonstrate that the peptidoglycan (PGN) that forms the cell wall of bacteria triggers an immediate feeding aversive response when detected by the gustatory system of adult flies. Although we identify ppk23+ and Gr66a+ gustatory neurons as necessary to transduce fly response to PGN, we demonstrate that they play very different roles in the process. Time-controlled functional inactivation andin vivocalcium imaging demonstrate that while ppk23+ neurons are required in the adult flies to directly transduce PGN signal, Gr66a+ neurons must be functional in larvae to allow future adults to become PGN sensitive. Furthermore, the ability of adult flies to respond to bacterial PGN is lost when they hatch from larvae reared under axenic conditions. Recolonization of axenic larvae, but not adults, with a single bacterial species,Lactobacillus brevis,is sufficient to restore the ability of adults to respond to PGN. Our data demonstrate that the genetic and environmental characteristics of the larvae are essential to make the future adults competent to respond to certain sensory stimuli such as PGN.

National audience; "En invoquant la décroissance, Timothée Parrique prône le développement d’un nouveau modèle économique délesté de la seule logique marchande. En résumé, affranchi du PIB."

The movement of animals is a central component of their behavioural strategies. Statistical tools for movement data analysis, however, have long been limited, and in particular, unable to account for past movement information except in a very simplified way. In this work, we propose MoveFormer, a new step-based model of movement capable of learning directly from full animal trajectories. While inspired by the classical step-selection framework and previous work on the quantification of uncertainty in movement predictions, MoveFormer also builds upon recent developments in deep learning, such as the Transformer architecture, allowing it to incorporate long temporal contexts. The model predicts an animal’s next movement step given its past movement history, including not only purely positional and temporal information, but also any available environmental covariates such as land cover or temperature. We apply our model to a diverse dataset made up of over 1550 trajectories from over 100 studies, and show how it can be used to gain insights about the importance of the provided context features, including the extent of past movement history. Our software, along with the trained model weights, is released as open source.

Within the set of risk factors that compromise the conservation of marine biodiversity, one of the least understood concerns is the noise produced by human operations at sea and from land. Many aspects of how noise and other forms of energy may impact the natural balance of the oceans are still unstudied. Substantial attention has been devoted in the last decades to determine the sensitivity to noise of marine mammals—especially cetaceans and pinnipeds—and fish because they are known to possess hearing organs. Recent studies have revealed that a wide diversity of invertebrates are also sensitive to sounds, especially via sensory organs whose original function is to allow maintaining equilibrium in the water column and to sense gravity. Marine invertebrates not only represent the largest proportion of marine biomass and are indicators of ocean health but many species also have important socio-economic values. This review presents the current scientific knowledge on invertebrate bioacoustics (sound production, reception, sensitivity), as well as on how marine invertebrates are affected by anthropogenic noises. It also critically revisits the literature to identify gaps that will frame future research investigating the tolerance to noise of marine ecosystems.

This paper deals with three related problems in a geostatistical context. First, some data are available for given areas of the space rather than for some point locations which creates problems of multiscale areal data. Second, some uncertainties rely both on the input locations and on measured quantities at these locations, involving uncertainty propagation problems. Third, multidimensional outputs can be observed, with sometimes missing data.These three problems are addressed simultaneously here by considering mixtures of multivariate random fields and by adapting standard Kriging methodology to this context. While the usual Gaussian setting is lost, we show that conditional mean, variance and covariance can be derived from this specific setting. Case studies are presented both with simulated data and real data. In particular, we discuss the question of information loss in learning buildings energy efficiency.

National audience; Cet ouvrage propose une réflexion commune sur la pandémie du virus Sars-CoV-2, par un groupe de chercheurs de différentes disciplines.Il s'agit de mieux la comprendre en la situant dans les différentes lignes temporelles qui la constituent, notamment celles de l’évolution démographique, de la multiplication des zoonoses et des mobilités liées aux mondialisations.Sont également étudiées les chronologies des dispositifs de surveillance ; des cadres politiques, économiques, juridiques de préparation aux crises ; des politiques de traitement des épidémies.Celles, aussi, de la résistance aux mesures sanitaires, de la gestion de crise en hôpital, en Ephad et du confinement familial, étudiant.Sans oublier les aspects essentiels de la réorganisation sociale, économique, de l’action sur l’avenir, à court, moyen et long terme et des crises écologiques plus globales du climat et de la biodiversité.

L’INRAE d’Aurillac mène des recherches sur la microbiologie et la technologie des fromages du Massif Central avec pour objectifs la compréhension des processus de fabrication et d’affinage des fromages et la recherche de solutions microbiennes et technologiques pour l’amélioration de leurs qualités. Leurs recherches ont ainsi contribué au maintien des prairies naturelles du Massif Central, au développement de l’activité économique, la création d’emplois et la reconnaissance internationale des fromages au lait cru. Cette étude a été conduite selon la méthode ASIRPA ex-post.; The INRAE of Aurillac carries out research on the microbiology and technology of cheeses from the Massif Central with the aim of understanding the manufacturing and ripening processes of cheeses and the search for microbial and technological solutions to improve their qualities. Their research has thus contributed to the maintenance of the natural meadows of the Massif Central, the development of economic activity, the creation of jobs and the international recognition of raw milk cheeses. Cette étude a été conduite selon la méthode ASIRPA ex-post.

Aquaculture can represent an alternative means of economic yield and food security. Despite this fact, consumers still have a more negative perception of farmed fish when compared with wild fish, including its sustainability. Understanding how consumers perceive sustainability is essential in building an effective strategy to encourage sustainable fish consumption. A survey with 2145 consumers was conducted in five European countries (France, Germany, Italy, Poland, and Spain) to inquire into consumers’ beliefs about the main pillars of the sustainability (environmental, social, and economic) when farmed and wild fish are compared, as well as to identify segments of consumers with similar beliefs about fish sustainability. Overall, results showed that European consumers perceived farmed fish as being more sustainable, locally obtained, providing environmental benefits, generating employment, improving human living conditions, generating rural development, and ensuring more fair fish prices than wild fish. Conversely, wild fish was perceived as ensuring animal welfare and being more organic but causing more environmental damage than farmed fish. Additionally, it seems that to effectively communicate aquaculture sustainability, it would be better to focus on single aspects of sustainability (beliefs) rather than focusing on the whole concept of sustainability. Finally, four segments of consumers were identified according to consumers’ beliefs, which were labelled accordingly: ambivalent, pro aquaculture, pro wild fish, and impartial. Results obtained may be helpful to provide each segment with tailored marketing strategies to stimulate farmed fish consumption and improve the overall image of the aquaculture sector to foster its full development in Europe. Objectius de Desenvolupament Sostenible::14 - Vida Submarina Objectius de Desenvolupament Sostenible::14 - Vida Submarina::14.2 - Per al 2020, gestionar i protegir de manera sostenible dels ecosistemes marins i costaners amb vista a evitar efectes nocius importants, fins i tot mitjançant l'enfortiment de la seva resiliència, i adoptar mesures de restauració a fi de restablir la salut i la productivitat dels oceans Objectius de Desenvolupament Sostenible::14 - Vida Submarina::14.5 - Per al 2020, conservar almenys el 10% de les zones costaneres i marines, de conformitat amb les lleis nacionals i el dret internacional i sobre la base de la millor informació científica disponible Objectius de Desenvolupament Sostenible::14 - Vida Submarina::14.a - Augmentar els coneixements científics, desenvolupar la capacitat de recerca i transferir la tecnologia marina, tenint en compte els criteris i directrius per a la transferència de tecnologia marina de la Comissió Oceanogràfica Intergovernamental, a fi de millorar la salut dels oceans i potenciar la contribució de la biodiversitat marina al desenvolupament dels països en desenvolupament, en particular els petits Estats insulars en desenvolupament i els països menys avançats Objectius de Desenvolupament Sostenible::14 - Vida Submarina::14.c - Millorar la conservació i l'ús sostenible dels oceans i els seus recursos aplicant el dret internacional reflectit en la Convenció de les Nacions Unides sobre el Dret del Mar, que proporciona el marc jurídic per a la conservació i la utilització sostenible dels oceans i els seus recursos, com es recorda en el paràgraf 158 del document "El futur que volem" Objectius de Desenvolupament Sostenible::2 - Fam zero

Organisms throughout their lives constantly modify their surrounding environment; such activities are often termed niche construction. An important property of niche construction is that its consequences can persist for a long period of time and several subsequent generations can be affected. This phenomenon is described as a time lag in niche construction, or ecological inheritance.Studies have suggested that time lag in niche construction can help avoiding the tragedy of the commons. In other words, it can lead to evolution of contribution to a common good, which is associated with positive niche construction, or to the limitation of a common bad, which is associated with negative niche construction.In this article, we will study the evolutionary consequences of incorporating time lags in a negative niche construction process: waste production. We consider a population that extrudes waste into its environment as it consumes resources to grow and reproduce. Higher consumption rates can lead to higher waste production. Individuals that adopt this selfish strategy are expected to be selected as toxic effects are equally shared among all individuals.We show that indeed this tragedy of the commons persists in many cases and selfish strategies evolve in general. When evolution is rapid and intragenerational time lag is incorporated, however, selfish strategies are no longer favoured and strategies resulting in less waste production can be selected. Importantly, heavy pollution results in smaller population sizes, so that drift becomes more important than natural selection and limits the evolution of higher waste production.

Parasites are omnipresent, and their eco-evolutionary significance has aroused much interest from scientists. Parasites may affect their hosts in many ways by altering host density, vulnerability to predation, and energy content, thus modifying profitability within the optimal foraging framework. Consequently, parasites could impact predator diet and trophic links through food webs. Here, we investigate the consequences of the iridovirus Daphnia iridescent virus 1 (DIV-1) infection on the reproductive success, mortality, appearance, mobility, and biochemical composition of water fleas (Daphnia magna), a widespread freshwater crustacean. We compare search time between infected and uninfectedDaphniapreyed by a common aquatic insect (Notonectasp.) as well as the handling time and feeding preference ofNotonectasp. Our findings show that infection does not change fecundity but reduces lifespan and thereby constrains fitness. InfectedDaphniashow reduced mobility and increased color reflectance in the UV and visible domains, which potentially affects their visibility and thus catchability. Infection increases body size and the amount of proteins but does not affect carbohydrate and lipid contents. Although infectedDaphniahad a longer handling time, they are preferred over uninfected individuals by aquatic insects. Taken together, our findings show that DIV-1 infection could makeDaphniamore profitable to predators (21% energy increase), a positive effect that should be balanced with density reductions due to higher mortalities. We also highlight that exposure to infection in asymptomatic individuals leads to ecological characteristics that differ from both healthy and symptomatic infected individuals.

Viruses are key players in marine ecosystems where they infect abundant marine microbes. RNA viruses are emerging as key members of the marine virosphere. They have recently been identified as a potential source of mortality in diatoms, a group of microalgae that accounts for roughly 40% of the primary production in the ocean. Despite their likely importance, their impacts on host populations and ecosystems remain difficult to assess. In this study, we introduce an innovative approach that combines automated 3D confocal microscopy with quantitative image analysis and physiological measurements to expand our understanding of viral infection. We followed different stages of infection of the bloom-forming diatom Guinardia delicatula by the RNA virus GdelRNAV-04 until the complete lysis of the host. From 20h after infection, we observed quantifiable changes in subcellular host morphology and biomass. Our microscopy monitoring also showed that viral infection of G. delicatula induced the formation of auxospores as a probable defense strategy against viruses. Our method enables the detection of discriminative morphological features on the subcellular scale and at high throughput for comparing populations, making it a promising approach for the quantification of viral infections in the field in the future.

International audience; Aim: Species-level traits, such as body and range sizes, are important correlates of extinction risk. However, both are often related and are driven by environmental factors. Here, we elucidated links between environmental factors, body size, range size and susceptibility to extinction, across the whole order of rodents. Location: Global. Time period: Current. Major taxa studied: Rodents (order Rodentia). Methods: We compiled an unprecedentedly large database of rodent morphology, phylogeny, range size, conservation status, global climate and normalized difference vegetation index (NDVI), comprising >86% of all described species. Using phylogenetic regressions, we initially explored the environmental factors driving body size. Next, we modelled the relationship between body size and range size. From this relationship, we computed and mapped (at the assemblage level) an index of relative range size, corresponding to the deviation from the expected range size of each species, given its body size. Finally, we tested whether relative range was correlated with the risk of extinction of the species derived from an assessment by the International Union for Conservation of Nature. Results: We found that, contrary to the expectations of Bergmann's rule, the body size of rodents was mostly influenced by variation in NDVI (rather than latitude/temperature). Body size, in turn, imposed a constraint on species range size, as evidenced by a triangular relationship that was segmented at the lower bound. The relative species range size derived from this relationship highlighted four geographical regions where rodents with small relative range were concentrated globally. We demonstrated that lower relative range size was associated with increased risk of extinction. Main conclusions: Species that, given their body size, are distributed across ranges that are smaller than expected have elevated extinction risk. Therefore, investigating the relationships between environmental drivers, body size and range size might help to detect species that could become threatened in the near future.

International audience; This opinion paper offers a scientific view on the current debate of the place of biodegradable plastics as part of the solution to deal with the growing plastic pollution in the world's soil, aquatic, and marine compartments. Based on the current scientific literature, we focus on the current limits to prove plastic biodegradability and to assess the toxicity of commercially used biobased and biodegradable plastics in natural environments. We also discuss the relevance of biodegradable plastics for selected applications with respect to their use and end of life. In particular, we underlined that there is no universal biodegradability of plastics in any ecosystem, that considering the environment as a waste treatment system is not acceptable, and that the use of compostable plastics requires adaptation of existing organic waste collection and treatment channels.

International audience; Wildfire is a common phenomenon in Mediterranean countries but the 2022 fire season has been extreme in southwest Europe (Portugal, Spain and France). Here we provide a preliminary but comprehensive analysis of 2022's wildfire sea-son in southwest Europe. Burned area has exceeded the 2001-2021 median by a factor of 52 in some regions and large wildfires (>500 ha) started to occur in June-July, earlier than the traditional fire season. These anomalies were asso-ciated with record-breaking values of fuel dryness, atmospheric water demand and pyrometeorological conditions. Live fuel moisture content was below the historical minima for almost 50 % of the season in some regions. A few large wildfires were responsible for 82 % of the burned area and, in turn, 47 % of the area burned occurred in protected areas. Shrublands, transitional woodlands and conifer forests (but not eucalypt plantations) were the land cover types most affected by extreme fires. As climate change intensifies, we can expect such fire seasons to become the new nor-mal in large parts of the continent, potentially leading to major negative impacts on rural economies. These results highlight the need for landscape level fuel management also in protected areas, to avoid fire-induced biodiversity losses and landscape scale degradation. Our results have important policy implications and indicate that fire preven-tion should be explicitly addressed within continental forest legislation and strategies.

International audience; Acoustic cameras, or imaging sonars, are high-potential devices for many applications in aquatic ecology, notably for fisheries management and population monitoring. However, how to extract such data into high-value information without a time-consuming entire data set reading by an operator is still a challenge. Moreover, the analysis of acoustic imaging, due to its low signal-to-noise ratio, is a perfect training ground for experimenting with new approaches, especially concerning deep learning techniques. We present hereby a novel approach that takes advantage of both convolutional neural network (CNN) and classical computer vision (CV) techniques, able to detect fish passages in acoustic video streams. The pipeline pre-treats the acoustic images to localise the signals of interest and to improve the detection performances. The YOLOv3-based model was trained with fish data from multiple species recorded by the two most frequently used models of acoustic cameras, the DIDSON and ARIS, including species of high ecological interest, as Atlantic salmon or European eels. The pre-treatment of images greatly improves the model performance, increasing its F1-score from 0.52 to 0.69. The model we developed provides satisfying results detecting almost 80% of fish passages and minimising the false-positive rate. On a validation data set, 40 h of videos and around 1 800 fish passages, the efficiency increases with the fish sizes, notably reaching a recall higher than 95% for Atlantic salmon. Conversely, the model appears much less efficient for eel detections on ARIS videos than on DIDSON data (31% recall vs 75%).

International audience; While the exploitation of aquatic fauna and flora has been documented in several primate species to date, the evolutionary contexts and mechanisms behind the emergence of this behavior in both human and non-human primates remain largely overlooked. Yet, this issue is particularly important for our understanding of human evolution, as hominins represent not only the primate group with the highest degree of adaptedness to aquatic environments, but also the only group in which true coastal and maritime adaptations have evolved. As such, in the present study we review the available literature on primate foraging strategies related to the exploitation of aquatic resources and their putative associated cognitive operations. We propose that aquatic resource consumption in extant primates can be interpreted as a highly site-specific behavioral expression of a generic adaptive foraging decision-making process, emerging in sites at which the local cost-benefit trade-offs contextually favor aquatic over terrestrial foods. Within this framework, we discuss the potential impacts that the unique intensification of this behavior in hominins may have had on the evolution of the human brain and spatial ecology.

On the climate-health issue, studies have already attempted to understand the influence of climate change on the transmission of malaria. Extreme weather events such as floods, droughts, or heat waves can alter the course and distribution of malaria. This study aims to understand the impact of future climate change on malaria transmission using, for the first time in Senegal, the ICTP's community-based vector-borne disease model, TRIeste (VECTRI). This biological model is a dynamic mathematical model for the study of malaria transmission that considers the impact of climate and population variability. A new approach for VECTRI input parameters was also used. A bias correction technique, the cumulative distribution function transform (CDF-t) method, was applied to climate simulations to remove systematic biases in the Coupled Model Intercomparison Project Phase 5 (CMIP5) global climate models (GCMs) that could alter impact predictions. Beforehand, we use reference data for validation such as CPC global unified gauge-based analysis of daily precipitation (CPC for Climate Prediction Center), ERA5-land reanalysis, Climate Hazards InfraRed Precipitation with Station data (CHIRPS), and African Rainfall Climatology 2.0 (ARC2). The results were analyzed for two CMIP5 scenarios for the different time periods: assessment: 1983-2005; near future: 2006-2028; medium term: 2030-2052; and far future: 2077-2099). The validation results show that the models reproduce the annual cycle well. Except for the IPSL-CM5B model, which gives a peak in August, all the other models (ACCESS1-3, CanESM2, CSIRO, CMCC-CM, CMCC-CMS, CNRM-CM5, GFDL-CM3, GFDL-ESM2G, GFDL-ESM2M, inmcm4, and IPSL-CM5B) agree with the validation data on a maximum peak in September with a period of strong transmission in August-October. With spatial variation, the CMIP5 model simulations show more of a difference in the number of malaria cases between the south and the north. Malaria transmission is much higher in the south than in the north. However, the results predicted by the models on the occurrence of malaria by 2100 show differences between the RCP8.5 scenario, considered a high emission scenario, and the RCP4.5 scenario, considered an intermediate mitigation scenario. The CanESM2, CMCC-CM, MCC-CMS, inmcm4, and IPSL-CM5B models predict decreases with the RCP4.5 scenario. However, ACCESS1-3, CSIRO, NRCM-CM5, GFDL-CM3, GFDL-ESM2G, and GFDL-ESM2M predict increases in malaria under all scenarios (RCP4.5 and RCP8.5). The projected decrease in malaria in the future with these models is much more visible in the RCP8.5 scenario. The results of this study are of paramount importance in the climate-health field. These results will assist in decision-making and will allow for the establishment of preventive surveillance systems for local climate-sensitive diseases, including malaria, in the targeted regions of Senegal.

International audience; Contrasting views of ecosystem services in seasonal wetlands of Gharb, Morocco.Submerged in winter, the seasonal wetlands (merjas) of the Gharb plain in Morocco were traditionally usedfor grazing in summer, alongside other productive uses. Yet, merjas were considered by the colonialadministration as unhealthy and unproductive environments, despite their abundance in natural resources.During the 20th century, the plain, including the merjas, was drained and irrigated to contribute to thenational objectives of food security and export of agricultural products. This article examines how local andinstitutional stakeholders view the merjas and the benefits they provide, through an analysis of ecosystemservices. While State institutions consider them as virgin lands to be developed and as potential flood controlbuffer zones to protect irrigated areas and cities, riverside communities consider them as productive lands,disadvantaged by occasional floods. The study shows contrasting views of ecosystem services, where eachstakeholder has a utilitarian vision of merjas. Despite the international debate on biodiversity and carbonstorage in wetlands, the ecological dimensions are rarely mentioned. The ecosystem services approachreveals the antagonisms between stakeholders, but can be a means of negotiating the future of merjas in aterritorial vision.; Immergés en hiver, les marais saisonniers (merjas) de la plaine du Gharb au Maroc étaient traditionnellement exploités pour le pâturage en été, à côté d'autres usages productifs. Pourtant, ils étaient considérés par l'administration coloniale comme des milieux insalubres et peu valorisés, malgré leur abondance en ressources naturelles. Au cours du XX e siècle, la plaine a fait l'objet d'un aménagement hydro-agricole, incorporant les merjas, pour contribuer aux objectifs nationaux de sécurité alimentaire et d'exportation de produits agricoles. Cet article interroge le regard porté par les acteurs locaux et institutionnels sur les merjas et les bénéfices qu'elles procurent, à travers une analyse des services écosystémiques. Si les institutions les considèrent comme des terres vierges à aménager et des zones tampon de régulation des crues pour protéger les secteurs aménagés et les villes, les collectivités riveraines les considèrent comme des espaces productifs, défavorisés par les crues. L'étude montre des visions contrastées des services écosystémiques, où chaque acteur a une vision utilitariste des merjas. Malgré le débat international sur la biodiversité et le stockage de carbone dans les zones humides, les dimensions écologiques sont peu citées. L'approche par les services écosystémiques dévoile les antagonismes entre acteurs, mais peut être un moyen de négociation sur le devenir des merjas dans une vision territoriale. Mots clés : zones humides temporaires / services écosystémiques / collectivité riveraine / acteurs institutionnels / Maroc

International audience; French rivers are subject to winter floods. The northern pike (Esox lucius) needs these, as it performs lateral migrations for breeding. On the contrary, the allochthonous European catfish (Silurus glanis) is known to be less active in winter. however, very few studies have focused on the behaviour of these two predatory fishes during winter floods. Thus, we propose to characterize their respective responses to high waters, using a radio telemetry approach: thirty northern pikes and seven European catfish were tagged with radio transmitters in the aisne river (northern France) and monitored between october 2020 and May 2021. as a result, some northern pikes and at least one catfish were recorded in the major bed, in various habitats, during two major floods. A "preferential zone" was identified for the northern pike and defined from the pre-flood positions; three types of behaviour were identified: "sedentary" pikes never left these zones, "returned" pikes left during floods but returned when the water level dropped, and "departed" pikes did not come back at all. Individuals from the departed group were significantly larger than those from the other two groups (5% threshold), and those in the sedentary group significantly smaller (10% threshold), suggesting a greater exploration capacity in experienced northern pikes. Meanwhile, the supposed winter quiescence of the European catfish can be questioned, as our observations highlight an adaptability to various conditions. These results also underline the importance of taking the major bed into account in riverine management policies. Résumé.-Comportement de deux poissons prédateurs Esox lucius linnaeus, 1758 et Silurus glanis linnaeus, 1758 lors de deux crues successives dans l'Aisne (France).; Les rivières françaises sont sujettes aux crues hivernales, et ces périodes d’inondation sont des événements importants pour le comportement du brochet commun (Esox lucius), qui effectue des migrations latérales pour se reproduire. Le silure glane (Silurus glanis), allochtone, est quant à lui connu pour être plutôt moins actif pendant l’hiver. Cependant, peu d’études ont été réalisées sur le comportement de ces deux poissons prédateurs lors des crues hivernales. Nous avons donc cherché à caractériser leurs réponses respectives à la montée des eaux à l’aide d’une approche de radio télémétrie. Trente brochets communs et sept silures glanes ont été marqués à l’aide d’émetteurs radio dans la rivière Aisne (Nord de la France), et suivis entre octobre 2020 et mai 2021. Un nombre important de brochets ainsi qu’au moins un silure ont été enregistrés dans le lit majeur, dans divers habitats inondés, lors des deux crues les plus importantes. Concernant les brochets, une “zone préférentielle” a été identifiée, et définie à partir des positions des individus avant les inondations. Trois types de comportements principaux ont été identifiés : les brochets “sédentaires” ne quittaient jamais ces zones, les brochets “explorateurs” les quittaient mais revenaient à la décrue, et les brochets “délaisseurs” n’y revenaient pas du tout. Les individus du groupe des délaisseurs étaient significativement plus gros que ceux des deux autres groupes au seuil de 5 %, et ceux du groupe des sédentaires significativement plus petits au seuil de 10 %. Ceci suggère une plus grande capacité d’exploration chez les brochets plus expérimentés. Concernant le silure glane, nos observations remettent en cause sa supposée quiescence et mettent en évidence l’adaptabilité de l’espèce à diverses conditions. Ces résultats soulignent l’importance de la prise en compte du lit majeur dans les politiques de gestion fluviale.