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R project code - Kerguelen_fish_composition
No full textAssessment of the nutritional composition of a range of fish samples collected around the Kerguelen Islands (Southern Indian Ocean) with a perspective on their role in nutrient cycling as prey.It is associated to the article by Gilbert et al. (2025) in JEMBE (https://doi.org/10.1016/j.jembe.2025.152097)This R project contains all the analysis of data conducted for this project from data exploration to modeling and result analysis.Targets set upThe project uses the targets packages (https://books.ropensci.org/targets/), and is therefore organized as follows:the R folder contains scripts containing functions and only functions (no direct command)functions are called in the _targets.R script at the root of this project, in items of a unique list. Each item in a list is defined by function tar_target(y, function(x)), in which y is a target object created by function(x) where function must be defined in the R folder and x must be a known object (usually, a target objet previously defined in the list)Each object from the list can be read using targets::tar_read(object) or loaded in the local environment with targets::tar_load(object).The full analysis can be run using targets::tar_make(), and only tasks associated to objects that are not up-to-date will be run.Note that the folder "work-in-progress" contains R scripts with direct commands which were used throughout the development of the project.Renv set upThe project also uses the Renv package (https://rstudio.github.io/renv/articles/renv.html). It helps in creating reproducible environments into R projects. Basic commands regarding Renv (e.g., update the environment) are contained in /dev-scripts/set-up-project.
Experimental study of microclimate benefits following de-sealing and revegetation in a parking lot.
No full textInternational audienceThis study investigates the evolution of microclimatic benefits following de-sealing of a 64 m² patch (Oasis) inside a parking lot located in the suburbs of Angers, France. Vegetation (trees and herbaceous species) was introduced. We compared the microclimate in the Oasis with that of a neighboring asphalt area (negative control), a meadow area (positive control), and under a tree in a sealed area (Figure 1). This comparison was conducted using on-site meteorological stations. Over the two years following de-sealing, microclimate variables were monitored, and thermal comfort was evaluated using the Universal Thermal Climate Index (UTCI) as vegetation developed. The Oasis experienced a significant reduction in surface temperature compared to surrounding asphalted areas, with a maximum decrease of 18.4°C during the first summer and 23.0°C during the second one. This cooling effect was attributed to the development of the herbaceous layer, which covered 60% of the Oasis three months after sowing and exceeded 90% coverage from the second year. The reduction in surface temperature contributed to improved daytime thermal comfort. Tree shading further enhanced local cooling, reducing UTCI by up to 8°C in shaded areas. No evidence of lower nocturnal air temperature compared to sealed reference areas was observed, possibly due to the patch's small size and air mixing with the surroundings. This study highlights that small-scale de-sealing and revegetation initiatives can deliver notable microclimate benefits in urban environments from the first year, with even greater impacts as vegetation matures, supporting urban adaptation to climate change
Deep‐sea ascending predation by king penguin and its prey reaction observed by animal‐borne video camera
No full textInternational audienc
Amélioration de l'évaluation du risque de glissement de terrain de la falaise basque par analyse quantitative
No full textInternational audienceThe Basque cliff coast, characterized by complex flysch formations, is highly susceptible to landslides (slides, rock-block slides, rockfalls). Despite ongoing monitoring, landslide hazard assessments remain limited, as they often focus on cliff retreat without fully integrating landslide dynamics. This study introduces a multidisciplinary and quantitative approach to improve hazard mapping. It combines historical cliff retreat analysis (1938–2018), landslide inventory compilation, susceptibility mapping using Bayesian models, and integration of temporal and intensity factors in hazard calculations. The results provide enhanced landslide hazard maps, offering a decision-support tool for stakeholders and local risk managers
Qualification des modèles de microclimat et des outils de simulation : une intercomparaison académique
No full textInternational audienceIn recent decades, numerous urban microclimate models have been developed to address various applications, such as diagnosing urban overheating and evaluating heat mitigation strategies using green or grey solutions. These models account for complex physical interactions; however, their qualification and validation remain significant challenges due to their complexity and the lack of a standardized framework and comprehensive reference datasets.This paper presents the first step of a comprehensive qualification and validation methodology through the definition of an academic benchmark and its application to four urban microclimate models. The proposed methodology follows an incremental phenomenological approach, systematically analysing heat transfer processes within an idealized street canyon with well-defined conditions across four cases: shortwave radiation, longwave radiation, aeraulics, and their coupling with heat conduction and storage in walls and ground. The benchmark aims to analyse the behaviour of different microclimate models, quantify deviations between simulation results, and identify their underlying sources within the physical models. This is achieved through the intercomparison of simulation results, incorporating reference data with a known standard deviation where available.The results show good agreement between models for solar radiation, infrared radiation, and heat conduction but reveal significant deviations in surface convection, stressing the need for further research into convection modelling and its influence on coupled processes. Additionally, the results confirm the suitability of the proposed methodology in identifying the sources of deviations between models. This benchmark provides a robust framework for model qualification and is expected to be widely adopted in future studies.Au cours des dernières décennies, plusieurs modèles de microclimat urbain ont été développés et utilisés pour diverses applications. Ces modèles permettent de diagnostiquer les surchauffes urbaines ou d'évaluer différentes stratégies d'atténuation de la chaleur, basées par exemple sur des solutions vertes ou grises, en tenant compte de toutes les interactions physiques. Cependant, leur validation reste un défi pour la recherche, en raison de leur complexité et de l'absence d'un cadre de qualification commun. Cet article propose et met en œuvre la première étape d'une méthodologie de qualification commune progressive par le biais d'un benchmark sur une étude de cas académique idéale, correspondant à un canyon de rue. La méthodologie proposée vise à analyser d'abord, de manière aussi indépendante que possible, les différents phénomènes physiques simulés, tels que le rayonnement solaire, le rayonnement infrarouge, l'aéraulique et la conduction thermique, puis leur couplage. Cette méthodologie a été appliquée à quatre modèles de microclimat urbain : MATHIS, SOLENE-Microclimat, SOLENE-SUSHI et TRABOULE-ProLB, mettant en évidence leurs capacités respectives, leurs similitudes et leurs différences. Dans l'ensemble, les résultats montrent une bonne correspondance pour le rayonnement solaire, le rayonnement infrarouge et la conduction thermique, mais des écarts significatifs pour la convection à la surface. Ces résultats soulignent l'importance de poursuivre les travaux de recherche sur la modélisation de la convection. Ils montrent également la pertinence de la méthodologie développée afin d'évaluer l'origine des divergences entre les modèles. Par conséquent, cette méthodologie devrait être appliquée plus largement à l'avenir
Case study on thermal and flow analysis of a water mist on a pool fire in a ventilated engine compartment
No full textInternational audienc
Widespread presence of metallic compounds and organic contaminants across Pacific coral reef fish
No full textInternational audienceCoral reef fishes represent an invaluable source of macro- and micro-nutrients for tropical coastal populations. However, several potentially toxic compounds may jeopardize their contribution to food security. Concentrations of metallic compounds and trace elements (MTEs), and persistent organic pollutants (POPs, including pesticides and polychlorobiphenyls PCBs), totalizing 36 contaminants, were measured in coral reef fish from several Pacific islands. The objective of this study was to describe the spatial distribution of these compounds and contaminants in order to identify potential variables explaining their distribution at a Pacific-wide scale. To achieve this, we applied Boosted Regression Trees to model species-specific and community-level contaminant and inorganic compound concentrations at the scale of the tropical Pacific Ocean. Overall, using 15 easily accessible explanatory variables, we successfully explained between 60 and 87 % of the global variation, with fish body size being the most important correlate of MTEs and POPs concentrations in reef fish. Our modeling approach allowed us to estimate and map the distribution of the community-level concentration of 19 contaminants and inorganic compounds at the scale of the equatorial and south Pacific Ocean. Spatial patterns varied significantly depending on the compound, with modeled quantities per 100 g of fish flesh generally being higher in the central and southwest Pacific than in the eastern part of the basin. These patterns were influenced by a combination of biological, environmental, anthropogenic and biogeographical variables. Overall, this approach represents an important step toward the estimation of concentrations of the main compounds on the basis of species identity and fishing location. Our results enhance our understanding of the extent of contamination in the Pacific while underscoring the urgent need for long-term and large-scale spatial monitoring of diverse compounds in this region
Le prestre qui ot mere a force - Édition, traduction et notes d'après le manuscrit Berlin, Staatsbibliothek und Preussischer Kulturbesitz, Hamilton 257
No full textÉdition, traduction et notes du Prestre qui ot mere a force d'après le manuscrit de Berlin, Staatsbibliothek und Preussischer Kulturbesitz, Hamilton 257
Le clerc qui fu repus derriere l'escrin - Jean de Condé - Édition, traduction et notes d'après le ms. BnF fr. 1446
No full textÉdition, traduction et notes du fabliau Le clerc qui fu repus derriere l'escrin d'après le ms. BnF fr. 83