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Habitat quality assessment of temperate forest ecosystems: An airborne LiDAR-based approach to predict the Index of Biodiversity Potential (IBP) at large scale
No full textInternational audienceThe Index of Biodiversity Potential (IBP) assesses the forest stand’s capacity to host species based on 10 structural, compositional, and environmental factors. Widely used by French forest managers, its reliance on in-situ surveys limits large-scale applications. While LiDAR-derived metrics can finely describe forest structure, their relationship with the IBP remains unexplored.We aimed to study these relationships with the IBP management factors, some of which reflect forest structure such as the number of large trees and vertical strata. Using a dataset of 1536 IBP plots across France, we computed LiDAR-derived structural metrics along with other variables (e.g., topographic, spectral). We then analysed their statistical relationships with the IBP factors, and calibrated predictive models using both regression and classification machine learning algorithms. Finally, we mapped the IBP management score for the first time over a 890 km area within the forests of the Ariege Pyrenees Regional Natural Park (France).The results revealed strong correlations between the IBP management score, its factors, and remote sensing metrics. LiDAR-derived metrics describing canopy height and vertical complexity were particularly important for prediction, as well as biomass and topographic metrics. Our best model, with an RMSE of 5.24 ± 0.63, predicts IBP within 5 points—a threshold beyond which variations reflect actual changes in species richness within the forest stand.These findings emphasise the relevance of remote sensing data, in particular LiDAR, for describing structural field metrics. They demonstrate that remote sensing offers a viable approach for large-scale IBP assessment
Probing the Cosmological Principle with CMB lensing and cosmic shear
No full textInternational audienceThe standard cosmological model assumes the Cosmological Principle. However, recent observations hint at possible violations of isotropy on large scales, possibly through late-time anisotropic expansion. Here we investigate the potential of cross-correlations between CMB lensing convergence and galaxy cosmic shear -modes as a novel probe of such late-time anisotropies. Our signal-to-noise forecasts reveal that information from the - cross-correlation is primarily contained on large angular scales (). We find that this cross-correlation for a Euclid-like galaxy survey is sensitive to anisotropy at the percent level. Making use of tomography yields a modest improvement of in detection power. Incorporating the galaxy - cross-correlations would further enhance these constraints
Evaluation of the barrier properties of biobased and biodegradable PHBV cups for a usage benefice in cheese applications
No full textInternational audienceThis study aims to characterize the barrier properties of polyhydroxyalkanoate cups (PHBV) or PHBV cups containing 20 % of cellulose fibers or 20 % of wood fibers in order to estimate the usage benefice in terms of food preservation to replace petrol-based packaging as polypropylene (PP), by bio-based and biodegradable PHBV packaging. For that, a previously developed model integrating (i) gases permeation through the lid film and the cup and (ii) sorption and diffusion of gases into the food (if any) was used. The O2 and CO2 permeabilities of PHBV were identified to 2.3 × 10−16 mol m−1.s−1.Pa−1 and 4.5 × 10−16 mol m−1.s−1.Pa−1 respectively at 23 °C, while the activation energy of these two parameters was estimated to 20.3 and 23.2 kJ mol−1 respectively. The integration of fibers in the PHBV packaging increased the gases permeabilities by a factor 11 to 23 for O2 and 5 to 10 for CO2, due to the presence of factures and holes in the cups. Based on the permeability values identified and thanks to 2D numerical simulation, it was concluded that PHBV packaging cups seems promising to replace PP packaging for products under modified atmosphere, and more specifically could maintain a similar shelf life than commercial packaging did for MAP product with intermediate shelf life such as fresh cheese
Genetic variation in molting time and its effects on growth and color traits in the Pacific blue shrimp Litopenaeus stylirostris
No full textInternational audienceTo grow and develop, shrimps must shed their exoskeletons. In shrimp an inter-individual variability in molting time is spread over about a week. The genetic basis of this variability and its implications for selective breeding programs to improve growth or quality traits remains largely unexplored.We estimated the effect of molting stage on genetic parameters of growth and color traits in the Pacific blue shrimp Litopenaeus stylirostris. As the variability of molting time may also be partly genetically determined, we estimated the heritabilities of molt stages and molting time under the hypothesis that some families may have the additive genetic potential to molt earlier (or later) than others.To address these questions, 1200 shrimp progenies (mean body weight 14.5 g) from 49 full- and half-sib families, bred according to a partly factorial design with double-sire insemination, were phenotyped over 3 successive days, 3 to 5 days before the full moon. Body weight, body length, head length and molt stage were recorded on uncooked shrimp and external color traits on uncooked or both uncooked and cooked shrimp.Molt stage had a significant phenotypic effect on all traits except for body length and head-to-length ratio. The heritability estimates for both growth and color traits were, however, similar in models with or without molting, and the estimated breeding values were highly correlated between these models.The heritability of molt stage with a four-class threshold model was low (0.07 [0.02–0.28]). When the stage classes were combined into just two to simplify the description of the molting process, the heritability of early or late molting was intermediate (from 0.16 [0.10–0.28] to 0.22 [0.13–0.40]), indicating that this trait is partly under additive genetic determinism rather than solely under environmental control. The genetic correlations of molting traits with body weight were not different from zero.These results are discussed for selective breeding practices and shrimp molting biology to consider in future study molting as a factor to improve selection practices for disease resistance, feed efficiency and robustness
Citizen science contributions to soil biodiversity research and conservation: insights from European studies
No full textInternational audienceCitizen science (CS) has emerged as a valuable approach for bridging knowledge gaps in biodiversity studies by expanding spatial and temporal coverage, yet remains underused in soil biodiversity monitoring. We conducted the first Europe-wide synthesis of CS initiatives dedicated to soil biodiversity, systematically reviewing published and unpublished projects to assess their contributions and limitations. A total of 126 papers and projects were analyzed across 36 countries, with Western European countries leading in study volume. National-scale studies dominated, with urban areas being the most studied land use type. Taxonomic coverage was broad but uneven, dominated by soil macrofauna (ants, gastropods and earthworms) and fungi. Methodologies ranged from opportunistic sampling to structured surveys, reflecting diverse scientific objectives and producing data of variable quality. Citizens contributed substantially to species identification, although verification practices varied widely, from expert validation to self-reported identifications without verification. Overall, our synthesis reveals a fragmented but dynamic CS landscape that, while providing valuable contributions, remains far from realizing its full scientific potential. Strengthening the role of CS in soil biodiversity research will require greater emphasis on taxonomic accuracy, with error rates systematically assessed. Emerging image-based identification tools, including community-based identification features and automated species recognition, offer promising avenues to enhance both taxonomic accuracy and participant engagement. Equally important is fostering inclusive participation to broaden spatial coverage and co-develop conservation-relevant indicators with stakeholders. Finally, dataset interoperability and metadata standardization are essential to integrate heterogeneous initiatives and unlock the full potential of CS for researchers and soil biodiversity monitoring frameworks
Editorial for research topic: Advancing mycorrhizal research for sustainable ecosystem and agricultural practices
No full textInternational audienceMycorrhizal symbiosis, a mutualistic association between plant roots and soil fungi, plays a crucial role in enhancing plant nutrition, stress tolerance, and overall adaptation to environmental conditions (van der Heijden et al., 2015). Despite the long-standing recognition of these benefits, research has primarily focused on understanding the mechanisms underlying the establishment and functioning of these interactions. Recent studies have highlighted the significant role of fungal hyphal networks in soil carbon storage, further emphasizing the ecological importance of mycorrhizal symbioses. However, there remain substantial gaps in our understanding of how these interactions can be optimized for both natural ecosystems and agricultural applications, especially under the increasing pressure of global climate change.The present Research Topic (RT) was initiated in the context of the 7 th French Mycorrhizal Days in Montpellier in May 2024, an international meeting bringing regularly together mycorrhizal research, students and companies from francophone countries (https://jmf7.journees.inrae.fr/). The RT aims to consolidate current research on mycorrhizal symbioses across various levels, from molecular and functional analyses to ecosystem studies and practical applications. The primary objective is to enhance our fundamental knowledge and to facilitate its translation into ecological and sustainable practices for plant growth, soil management, and ecosystem balance. The call for papers attracted several contributions, Mycorrhizal symbiosis is tightly regulated by host plants and fungi and requires major root cell and fungal hyphae reprogramming to form structures enabling nutrient exchange (Choi et al., 2018;Ho-Plágaro and García-Garrido, 2022). Specific molecular players and mechanisms involved in the establishment of arbuscular mycorrhizal (AM) symbioses were investigated in two studies. Strigolactones, phytohormones with dual signalling functions within plant roots and in rhizosphere interactions (Al-Babili and Bouwmeester, 2015), have been demonstrated to impact spore germination and hyphal branching affecting in turn root colonization by AM fungi (Akiyama et al., 2010). Here, Klein et al. analyzed strain-specific impacts of strigolactones using two Rhizophagus irregularis strains and their response regarding germination and pre-symbiotic growth. Observed strain-specific differences may Impact of AM fungi on plant performance was analyzed by Alayafi et al. for two crop plants, sunflower (Helianthus annuus) and pumpkin (Cucurbita pepo), under field conditions for two years. Inoculation with the AM fungus Funneliformis mosseae improved plant nutrient uptake, biomass and specifically oil yield and quality, dependent on possible synergistic effects of intercropping (Reddy et al., 2023). Such field studies, going beyond laboratory work under controlled and limited conditions, underline the importance of beneficial interactions for modern agriculture. In turn, Battie-Laclau et al. reported also that the vineyard's "terroir", understood as a cultivated ecosystem where grapevine interacts with their natural environment, is critical for the composition of the microbiota community. On the other hand, agricultural practices promoting AM fungi in grapevine cultures have been long time neglected as massive fungicide treatments were needed to protect vineyards. Only since recently, with the increasing demand for more natural culture conditions, research is focalizing on promoting AM fungi in vineyards through the use of more organic management practices. Such changes promoting agroecology (Jindo et al., 2022) will induce higher diversity of AM communities and thus determine the future sustainable development of vineyards over next decades. This study showed the dominant effect of geographical effects, AM communities mainly be structured by terroir even before practice, underscoring the necessity for future studies on fungal inoculation in vineyards to consider the specific characteristics of each terroir.Another important topic is the impact and use of beneficial interactions for a better adaptation of plants to challenging environmental conditions and climate change. Mycorrhizal symbioses, among other beneficial associations, are playing a decisive role in improving plant tolerance to abiotic and biotic stress (Usman et al., 2021). Regarding other beneficial interactions, Hassan et al. focalized on plant growth-promoting bacteria (PGPB, Micromonospora sp) and demonstrated their role in mitigating effects on heat stress in wheat by metabolic adaptations enhancing photosynthetic efficiency and antioxidant defence. The importance of AM symbiosis for the bioavailability of essential micronutrients in wheat has been recently highlighted (Nguyen et al., 2025). In a more general context, Lethielleux-Juge reviewed the impact of mycorrhizal symbioses and associated soil microbiomes in ecological restoration. The use of AM fungi, both natives or exotic, have been widely reported in ecosystem restoration (De Moura et al., 2022). AM fungi grow at diverse soil conditions, colonizing most plant species (from herbs to trees), and can evolve together with plants after revegetation. Moreover, the interaction of AM fungi with different ectomycorrhizal fungi, PGPB, rhizobacteria and mycorrhiza-helper bacteria will allow to improve soil attributes and plant adaptation to stress in a complex network of plant-soil-microbiomes with high relevance in ecosystem dynamics.In summary, studies included in this RT are dealing with a broad panel of questions regarding our insight in and application of beneficial mycorrhizal interactions. Further questions concern still better understanding of mycorrhizal networks in natural ecosystems, in soil carbon storage, and under diverse challenging abiotic and biotic environmental conditions.For scientifically based agricultural applications, best practices for managing plant-soil biota on the field-scale will have to include whole microbiome interactions
Checking methodology and statistics when reading an observational study
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Reconstructing the freshwater paleoecosystems diversity of Toros-Menalla (Late Miocene, Chad) from an integrated faunal perspective
No full textAquatic environments are critical components of past ecosystems that shaped species distribution and survival. Yet in hominin-bearing fossil sites, they are often treated as uniform or poorly detailed elements of “mosaic” landscapes, failing to capture their ecological complexity. In the northern Chad Basin, the late Miocene Toros-Menalla area records vast perilacustrine systems where aquatic and terrestrial ecosystems were deeply interconnected. While terrestrial vertebrate assemblages have been well characterised as reflecting a heterogeneous landscape, the aquatic component remains poorly resolved. Variations in depositional settings, aquatic vertebrate diversity, stable isotope data, and field observations point to a more complex and dynamic network of freshwater habitats. An integrative study of aquatic and semi-aquatic vertebrate assemblages from five Toros-Menalla sites reveals distinct faunal structures reflecting different ecological preferences and depositional conditions, ranging from perilacustrine floodplains to swampy, vegetated, or marginal waters and large open waterbodies with current. These environments, distributed across several hundreds of meters up to 30 km, represent lateral habitat diversity rather than temporal succession, as most assemblages formed geologically instantaneously (except for TM266, where vertical mixing could be hypothesised). Comparison with the present-day Bol Archipelago on the northeastern shores of Lake Chad provides a suitable analogue for the Toros-Menalla paleoenvironment. There, interdunal water bodies of varying depth and connectivity create a dynamic network of aquatic habitats at a similar spatial scale. This study underscores the need for systematic, grid-based collection and sieving of fossils to capture representative aquatic biodiversity and structure, and to reconstruct freshwater paleoenvironments with greater ecological precision
MobiCT: a UMI-based circulating tumor DNA analysis pipeline
No full textInternational audienceMobiCT is a bioinformatics pipeline designed to detect ultra-low-frequency variants present in cell-free DNA samples using unique molecular identifier (UMI). The pipeline is composed of three main stages: (i) UMI deduplication, (ii) alignment to reference genome, and (iii) variant calling. It has been validated using a range of cancer patients and control samples, demonstrating sensitivity, precision, and F1-score around 90%. Implemented in Nextflow, following the nf-core guidelines, MobiCT ensures reliability and reproducibility, making it suitable for both research and clinical applications
Shaping research in marine functional connectivity for integrated and effective marine science and management
No full textInternational audienceEffective knowledge of ecological connectivity at sea and at the land-sea interface is key to supporting global policy goals to conserve and restore ocean biodiversity and function. However, a persistent lack of commonality in terminology and understanding around the concept of marine connectivity hampers its application in spatial planning and policy, and its integration across disciplines. Building on an extensive literature review, we clarify definitions and subcategories of connectivity, and propose a unified conceptual framework for Marine Functional Connectivity (MFC) research to support multidisciplinary marine science for improved management and policy. We identify key challenges and future directions for advancing this emerging field, bringing together most strands of marine science to understand changes in biodiversity and functional interdependencies between habitats and regions. Placing MFC research at the heart of marine environmental science promises to significantly improve predictions of environmental and socio-economic change and the sustainable use of ecosystems and resources at sea and at the land-sea interface