Author: "Laboratoire National d’Hydraulique et Environnement (EDF R - Searchworks@Jio Institute Digital Library Search Results

Your search keyword '"Laboratoire National d’Hydraulique et Environnement (EDF R' showing total 248 results

Start Over Author "Laboratoire National d’Hydraulique et Environnement (EDF R

248 results on '"Laboratoire National d’Hydraulique et Environnement (EDF R'

1. Habitat partitioning among three predatory fish in a temperate reservoir

Author: Frédéric Santoul, Samuel Westrelin, Romain Roy, Laurence Tissot, Christine Argillier, Julien Cucherousset, Risques, Ecosystèmes, Vulnérabilité, Environnement, Résilience (RECOVER), Aix Marseille Université (AMU)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Evolution et Diversité Biologique (EDB), Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées, EDF R&D LNHE - Laboratoire National d’Hydraulique et Environnement, Chatou Cedex, France, HYNES team (INRAE-EDF E&D), Chatou, France, Laboratoire Ecologie Fonctionnelle et Environnement (ECOLAB), Institut Ecologie et Environnement (INEE), Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées, Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS), Laboratoire National d’Hydraulique et Environnement (EDF R&D LNHE), EDF R&D (EDF R&D), EDF (EDF)-EDF (EDF), Laboratoire Ecologie Fonctionnelle et Environnement (LEFE), Université de Toulouse (UT)-Université de Toulouse (UT)-Observatoire Midi-Pyrénées (OMP), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), and Université de Toulouse (UT)
Subjects: 0106 biological sciences, Ecology, 010604 marine biology & hydrobiology, vertical habitat use, 15. Life on land, Aquatic Science, Biology, 010603 evolutionary biology, 01 natural sciences, 6. Clean water, Esox lucius, Perca fluviatilis, Predatory fish, Habitat, littoral -pelagic habitat use, Temperate climate, 14. Life underwater, [SDE.BE]Environmental Sciences/Biodiversity and Ecology, Ecology, Evolution, Behavior and Systematics, Sander lucioperca, diel and seasonal habitat use
Abstract: International audience; The diversity of predatory species plays a key role in ecosystem functioning but our understanding of the mechanisms underlying their coexistence is limited, particularly in freshwater ecosystems. Northern pike Esox lucius, European perch Perca fluviatilis and pikeperch Sander lucioperca are three widespread predatory species 2 in European lakes, where they often coexist. As potential competitors, we hypothesized that partitioning habitat is a determinant of species coexistence. This was tested by quantifying the variability of their habitat use in tracking adult individuals in the Bariousses reservoir (France, 86.6 ha, mean depth 7.1 m). Specifically, we investigated their distribution along the littoral-pelagic and depth axes along the daily cycle and across seasons. From littoral to pelagic waters were first found pike, then perch and finally pikeperch. Pike was the closest to the surface while pikeperch was the deepest. This general pattern was, however, variable across seasons with the three species located in the upper layer in summer during reservoir stratification. Individuals were more evenly distributed along the littoral-pelagic axis and closer to the bottom when water was mixing (autumn, winter). In summer, perch used more intensively the pelagic zone during daytime. Other species did not show any diel change of habitats. Our results highlighted that species coexistence is associated with habitat partitioning among these three predators, with perch showing a more variable behaviour regarding habitat characteristics. Now more than ever, in the context of global change which modifies habitats, it is of crucial importance to understand coexistence mechanisms of species that shape ecosystems.
Published: 2021

2. Assessment of one-way coupling methods from a potential to a viscous flow solver based on domain- and functional-decomposition for fixed submerged bodies in nonlinear waves

Author: Michel Benoit, Fabien Robaux, Institut de Recherche sur les Phénomènes Hors Equilibre (IRPHE), Aix Marseille Université (AMU)-École Centrale de Marseille (ECM)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Hydraulique Saint-Venant / Saint-Venant laboratory for Hydraulics (LHSV), École des Ponts ParisTech (ENPC)-Centre d'Etudes et d'Expertise sur les Risques, l'Environnement, la Mobilité et l'Aménagement (Cerema)-EDF R&D (EDF R&D), EDF (EDF)-EDF (EDF), École Centrale de Marseille (ECM), Laboratoire National d’Hydraulique et Environnement (EDF R&D LNHE), and EDF R&D (EDF R&D)
Subjects: Physics::Fluid Dynamics, Fluid-structure interaction, Potential-viscous coupling, Functional decomposition, Fluid Dynamics (physics.flu-dyn), FOS: Physical sciences, General Physics and Astronomy, Physics - Fluid Dynamics, Domain decomposition, [PHYS.MECA.MEFL]Physics [physics]/Mechanics [physics]/Fluid mechanics [physics.class-ph], Nonlinear water waves, Coupling methods, Mathematical Physics
Abstract: To simulate the interaction of ocean waves with marine structures, coupling approaches between a potential flow model and a viscous model are investigated. The first model is a fully nonlinear potential flow (FNPF) model based on the Harmonic Polynomial Cell (HPC) method, which is highly accurate and best suited for representing long distance wave propagation. The second model is a CFD code, solving the Reynolds-Averaged Navier-Stokes (RANS) equations within the \openfoam toolkit, more suited to represent viscous and turbulent effects at local scale in the body vicinity. Two one-way coupling strategies are developed and compared in two dimensions, considering fully submerged and fixed structures. A domain decomposition (DD) strategy is first considered, introducing a refined mesh in the body vicinity on which the RANS equations are solved. Boundary conditions and interpolation operators from the FNPF results are developed in order to enforce values at its outer boundary. The second coupling strategy considers a decomposition of variables (functional decomposition, FD) on the local grid. As the FNPF simulation provides fields of variables satisfying the irrotational Euler equations, complementary velocity and pressure components are introduced as the difference between the total flow variables and the potential ones. Those complementary variables are solutions of modified RANS equations. Comparisons are presented for nonlinear waves interacting with a horizontal cylinder of rectangular cross-section. The loads exerted on the body computed from the four simulation methods (standalone FNPF, standalone CFD, DD and FD coupling schemes) are compared with experimental data. It is shown that both coupling approaches produce an accurate representation of the loads and associated hydrodynamic coefficients over a large range of incident wave steepness and Keulegan-Carpenter number., Comment: 39 Pages, 12 figures, 2 tables
Published: 2022

3. The ecological causes of functional distinctiveness in communities

Author: Munoz, François, Klausmeier, Christopher A, Gaüzère, Pierre, Kandlikar, Gaurav, Litchman, Elena, Mouquet, Nicolas, Ostling, Annette, Thuiller, Wilfried, Algar, Adam C, Auber, Arnaud, Cadotte, Marc W, Delalandre, Léo, Denelle, Pierre, Enquist, Brian J, Fortunel, Claire, Grenié, Matthias, Loiseau, Nicolas, Mahaut, Lucie, Maire, Anthony, Mouillot, David, Pimiento, Catalina, Violle, Cyrille, Kraft, Nathan J B, Laboratoire Interdisciplinaire de Physique [Saint Martin d’Hères] (LIPhy ), Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA), Michigan State University [East Lansing], Michigan State University System, Laboratoire d'Ecologie Alpine (LECA ), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA), University of Missouri [Columbia] (Mizzou), University of Missouri System, Laboratoire Service d' Experimentations Aquacoles [Palavas les Flots] (LSEA MARBEC), MARine Biodiversity Exploitation and Conservation (UMR MARBEC), Institut de Recherche pour le Développement (IRD)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Institut de Recherche pour le Développement (IRD)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM), University of Texas at Austin [Austin], Laboratoire Environnement de Conception & Architecture (LECA), Université Paris-Saclay-Département Systèmes et Circuits Intégrés Numériques (DSCIN), Laboratoire d'Intégration des Systèmes et des Technologies (LIST (CEA)), Direction de Recherche Technologique (CEA) (DRT (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Direction de Recherche Technologique (CEA) (DRT (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Laboratoire d'Intégration des Systèmes et des Technologies (LIST (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Lakehead University, Laboratoire Ressources Halieutiques (LRH), Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER), University of Toronto at Scarborough, Centre d’Ecologie Fonctionnelle et Evolutive (CEFE), Université Paul-Valéry - Montpellier 3 (UPVM)-École Pratique des Hautes Études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud])-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut Agro Montpellier, Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Université de Montpellier (UM), Georg-August-University = Georg-August-Universität Göttingen, University of Arizona, Botanique et Modélisation de l'Architecture des Plantes et des Végétations (UMR AMAP), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud])-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université de Montpellier (UM), German Centre for Integrative Biodiversity Research (iDiv), Centre de Synthèse et d’Analyse sur la Biodiversité (CESAB), Fondation pour la recherche sur la Biodiversité (FRB), Laboratoire National d’Hydraulique et Environnement (EDF R&D LNHE), EDF R&D (EDF R&D), EDF (EDF)-EDF (EDF), Universität Zürich [Zürich] = University of Zurich (UZH), University of California (UC), University of Zurich, and Munoz, François
Subjects: Ecology, source, Evolution, Community assembly, Fitness landscape, 10125 Paleontological Institute and Museum, 1105 Ecology, Evolution, Behavior and Systematics, 560 Fossils & prehistoric life, Behavior and Systematics, [SDE]Environmental Sciences, Source-sink dynamics, sink dynamics, Coexistence, Ecological interactions, Functional traits
Abstract: International audience; Recent work has shown that evaluating functional trait distinctiveness, the average trait distance of a species to other species in a community offers promising insights into biodiversity dynamics and ecosystem functioning. However, the ecological mechanisms underlying the emergence and persistence of functionally distinct species are poorly understood. Here, we address the issue by considering a heterogeneous fitness landscape whereby functional dimensions encompass peaks representing trait combinations yielding positive population growth rates in a community. We identify four ecological cases contributing to the emergence and persistence of functionally distinct species. First, environmental heterogeneity or alternative phenotypic designs can drive positive population growth of functionally distinct species. Second, sink populations with negative population growth can deviate from local fitness peaks and be functionally distinct. Third, species found at the margin of the fitness landscape can persist but be functionally distinct. Fourth, biotic interactions (positive or negative) can dynamically alter the fitness landscape. We offer examples of these four cases and guidelines to distinguish between them. In addition to these deterministic processes, we explore how stochastic dispersal limitation can yield functional distinctiveness. Our framework offers a novel perspective on the relationship between fitness landscape heterogeneity and the functional composition of ecological assemblages.
Published: 2023

4. Modelling the atmospheric chlorine 36 dry deposition on grass usingmicrometeorology

Author: Sourabie, Déo-Gratias, Hebert, Didier, Lourino-Cabana, Beatriz, Benedetti, Lucilla, Vitorge, Elsa, Guillou, Valery, Maro, Denis, Laboratoire de Radioécologie de Cherbourg-Octeville (IRSN/PSE-ENV/SRTE/LRC), Service de recherche sur les transferts et les effets des radionucléides sur les écosystèmes (IRSN/PSE-ENV/SRTE), Institut de Radioprotection et de Sûreté Nucléaire (IRSN)-Institut de Radioprotection et de Sûreté Nucléaire (IRSN), Centre européen de recherche et d'enseignement des géosciences de l'environnement (CEREGE), Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Collège de France (CdF (institution))-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Laboratoire National d’Hydraulique et Environnement (EDF R&D LNHE), EDF R&D (EDF R&D), EDF (EDF)-EDF (EDF), EDF DIPDE, IRSN, EDF, and European Geosciences Union
Subjects: [SDU]Sciences of the Universe [physics], [SDE]Environmental Sciences, Dry deposits, chlorine 36, AMS, Micrometeorology, Modelling
Abstract: International audience; Chlorine 36 (36Cl, T1/2 = 301,000 years) is a radionuclide with natural and anthropogenic origin that can be rejected during decommissioning of nuclear power plants or chronically during recycling of used nuclear fuels. Once emitted into the atmosphere, chlorine 36 (gas and particles) can be transferred to the soil and vegetation cover by dry and wet deposition. However, quantitative constraints of these deposits are very scarce. Because of its relatively high mobility in the geosphere and its high bioavailability, chlorine 36 fate in the environment should be studied for environmental and human impact assessments. The aim of this study is therefore to develop dry depositional models for the gaseous and particulate fractions of chlorine 36. The model used for the parameterization of gaseous chlorine 36 dry deposition on grass is the << Big-leaf >> model based on the electrical analogy (Seinfield 1985). It was adapted from the Bah (2020) model developed for iodine. For particulate chlorine 36, the Damay Pellerin (2017) model was used. This model requiring the diameter of particulate chlorine 36 to be known, a sample of aerosol was taken in the chlorine 36 plume to determine on which particle size it is fixed. The sampling was performed on a low pressure impinger (LPI, DEKATI) of 13 levels for particles with diameters between 30nm and 10μm. In order to obtain model input data, meteorological and micrometeorological parameters were measured continuously at the IRSN La Hague technical platform (PTILH, France). The PTILH is located 2 km north of Orano La-Hague plant which emits small quantities of chlorine 36. An ultrasonic anemometer (Young 81000V) installed at a height of 4,5 m from the ground measured the direction (°), the velocity u (m/s) and the air friction velocity u* (m/s), the sensible heat flux H, the Monin-Obukhov length (L) and the atmospheric stability (1/L). A weather station (Spectrum Watchdog, series 2000) measured temperature Ts (°C), relative humidity RH (%), dew point (°C), global radiation SR (Wat/m^2) and photosynthetic active radiation PAR (μM/m^2.s). Sampling campaigns of 2 weeks were also conducted at the PTILH site to determine experimental depositional rates of chlorine 36. Chlorine 36 measurements were carried out by acceleration mass spectrometry at CEREGE-LN2C (France).The particle size distribution of the aerosol sample from chlorine 36 plume shows two peaks, a main one at 2μm and a second one at 10μm, typical distribution of marine aerosol. The modelsyield chlorine 36 depositional velocities between 6,7.10-3 and 10-2 m/s for the particulate fraction,and between 5.10-3 and 1,3.10-2 m/s for the gaseous one. The total dry depositional velocities(particles and gas) calculated from the model are less than one order of magnitude than the onesobtained experimentally.
Published: 2023

5. Equilibration process of out-of-equilibrium sea-states induced by strong depth variation: Evolution of coastal wave spectrum and representative parameters

Author: Yuxiang Ma, Jie Zhang, Michel Benoit, Dalian University of Technology, Laboratoire National d’Hydraulique et Environnement (EDF R&D LNHE), EDF R&D (EDF R&D), EDF (EDF)-EDF (EDF), Laboratoire d'Hydraulique Saint-Venant / Saint-Venant laboratory for Hydraulics (LHSV), École des Ponts ParisTech (ENPC)-Centre d'Etudes et d'Expertise sur les Risques, l'Environnement, la Mobilité et l'Aménagement (Cerema)-EDF R&D (EDF R&D), Institut de Recherche sur les Phénomènes Hors Equilibre (IRPHE), and Aix Marseille Université (AMU)-École Centrale de Marseille (ECM)-Centre National de la Recherche Scientifique (CNRS)
Subjects: [SDU.OCEAN]Sciences of the Universe [physics]/Ocean, Atmosphere, Environmental Engineering, Ocean Engineering, [PHYS.MECA.MEFL]Physics [physics]/Mechanics [physics]/Fluid mechanics [physics.class-ph], ComputingMilieux_MISCELLANEOUS
Abstract: International audience; Recent studies showed both experimental and numerical evidence that the occurrence probability of freak waves could be significantly enhanced as results of non-equilibrium dynamics induced by strong depth variations. The sea-state is characterized by strong non-Gaussian behavior in a short spatial extent after the depth transition, covering a few wavelengths. In this work, we investigate the complete equilibration process of an out-of-equilibrium sea-state via high-fidelity numerical simulations. In the simulations, the region after the depth transition is set as long as around one hundred wavelengths, such that the spectral adaptation develops and terminates eventually. The results are analyzed with spectral, cross-spectral and statistical approaches. It is shown that there are two stages with different spatial scales in the equilibration process. In the short scale, the sea-state is characterized by significant changes in wave statistics, freak wave occurrence probability is intensified. In the long scale, the wave spectrum undergoes strong modulation, the spectral peak disintegrate into a relative broad band, and low-frequency waves are enhanced as well. We show evidence that the spectral changes in the long scale are due to interactions of free components. The wave nonlinearity is shown to be positively correlated to the magnitude of the dynamical responses, but irrelevant to the length of the spatial scales in the equilibration process. In the established shallow-water equilibrium, the freak wave occurrence probability becomes less than Gaussian expectation and the waves are asymmetric in the vertical direction and symmetric in the horizontal.
Published: 2023

6. Tracking a killer shrimp: Dikerogammarus villosus invasion dynamics across Europe

Author: Ismael Soto, Ross N. Cuthbert, Danish A. Ahmed, Antonín Kouba, Sami Domisch, Jaime R. G. Marquez, Ayah Beidas, Giuseppe Amatulli, Jens Kiesel, Longzhu Q. Shen, Margarita Florencio, Herlander Lima, Elizabeta Briski, Florian Altermatt, Gaït Archambaud‐Suard, Peter Borza, Zoltan Csabai, Thibault Datry, Mathieu Floury, Maxence Forcellini, Jean‐François Fruget, Patrick Leitner, Marie‐Hélène Lizée, Anthony Maire, Anthony Ricciardi, Ralf B. Schäfer, Rachel Stubbington, Gea H. Van der Lee, Gábor Várbíró, Ralf C. M. Verdonschot, Peter Haase, Phillip J. Haubrock, South Bohemian Research Center of Aquaculture and Biodiversity of Hydrocenoses [University of South Bohemia] (CENAKVA), Faculty of Fisheries and Protection of Waters [University of South Bohemia], University of South Bohemia -University of South Bohemia, Helmholtz Centre for Ocean Research [Kiel] (GEOMAR), Queen's University [Belfast] (QUB), Gulf University for Science and Technology (GUST), Leibniz Institute of Freshwater Ecology and Inland Fisheries (IGB), Yale University [New Haven], Christian-Albrechts University of Kiel, Risques, Ecosystèmes, Vulnérabilité, Environnement, Résilience (RECOVER), Aix Marseille Université (AMU)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), RiverLy - Fonctionnement des hydrosystèmes (RiverLy), Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Laboratoire d'Ecologie des Hydrosystèmes Naturels et Anthropisés (LEHNA), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-École Nationale des Travaux Publics de l'État (ENTPE)-Centre National de la Recherche Scientifique (CNRS), ARALEP, Laboratoire National d’Hydraulique et Environnement (EDF R&D LNHE), EDF R&D (EDF R&D), EDF (EDF)-EDF (EDF), Universität Duisburg-Essen = University of Duisburg-Essen [Essen], Senckenberg Research Institute and Natural History Museum [Frankfurt], Senckenberg – Leibniz Institution for Biodiversity and Earth System Research - Senckenberg Gesellschaft für Naturforschung, Leibniz Association-Leibniz Association, Leverhulme TrustECF-2021-001, Federal Ministry of Education & Research (BMBF)033W034A, European Project: 871128,eLTER PLUS (2020), UNIVERSITY OF SOUTH BOHEMIA CESKE BUDEJOVICE CZE, Partenaires IRSTEA, Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA), and Kuwait Foundation for the Advancement of Sciences (KFAS)PR1914SM-01
Subjects: invasive alien species, Water and Food, time-series, [SDE.MCG]Environmental Sciences/Global Changes, long-term monitoring, Water en Voedsel, biological invasion, freshwater ecosystem, SDG 3 - Good Health and Well-being, [SDE]Environmental Sciences, crustacean, [SDE.BE]Environmental Sciences/Biodiversity and Ecology, Biologie, Ecology, Evolution, Behavior and Systematics, SDG 15 - Life on Land
Abstract: AimInvasive alien species are a growing problem worldwide due to their ecological, economic and human health impacts. The “killer shrimp” Dikerogammarus villosus is a notorious invasive alien amphipod from the Ponto-Caspian region that has invaded many fresh and brackish waters across Europe. Understandings of large-scale population dynamics of highly impactful invaders such as D. villosus are lacking, inhibiting predictions of impact and efficient timing of management strategies. Hence, our aim was to assess trends and dynamics of D. villosus as well as its impacts in freshwater rivers and streams.LocationEurope.MethodsWe analysed 96 European time series between 1994 and 2019 and identified trends in the relative abundance (i.e. dominance %) of D. villosus in invaded time series, as well as a set of site-specific characteristics to identify drivers and determinants of population changes and invasion dynamics using meta-regression modelling. We also looked at the spread over space and time to estimate the invasion speed (km/year) of D. villosus in Europe. We investigated the impact of D. villosus abundance on recipient community metrics (i.e. abundance, taxa richness, temporal turnover, Shannon diversity and Pielou evenness) using generalized linear models.ResultsPopulation trends varied across the time series. Nevertheless, community dominance of D. villosus increased over time across all time series. The frequency of occurrences (used as a proxy for invader spread) was well described by a Pareto distribution, whereby we estimated a lag phase (i.e. the time between introduction and spatial expansion) of approximately 28 years, followed by a gradual increase before new occurrences declined rapidly in the long term. D. villosus population change was associated with decreased taxa richness, community turnover and Shannon diversity.Main ConclusionOur results show that D. villosus is well-established in European waters and its abundance significantly alters ecological communities. However, the multidecadal lag phase prior to observed spatial expansion suggests that initial introductions by D. villosus are cryptic, thus signalling the need for more effective early detection methods.
Published: 2023

7. Two-dimensional modeling of fine sediment transport with mixed sediment and consolidation: Application to the Gironde Estuary, France

Author: Sylvain Orseau, Fabrice Klein, Pablo Tassi, Damien Pham Van Bang, Nicolas Huybrechts, Centre d'Etudes et d'Expertises sur les Risques, l'Environnement, la Mobilité et l'Aménagement - Equipe-projet HA (Cerema Equipe-projet HA), Centre d'Etudes et d'Expertise sur les Risques, l'Environnement, la Mobilité et l'Aménagement (Cerema), Roberval (Roberval), Université de Technologie de Compiègne (UTC), Centre d'Etudes et d'Expertise sur les Risques, l'Environnement, la Mobilité et l'Aménagement - Equipe-projet HA (Cerema Equipe-projet HA), Laboratoire National d’Hydraulique et Environnement (EDF R&D LNHE), EDF R&D (EDF R&D), EDF (EDF)-EDF (EDF), Laboratoire d'Hydraulique Saint-Venant / Saint-Venant laboratory for Hydraulics (Saint-Venant), École des Ponts ParisTech (ENPC)-Centre d'Etudes et d'Expertise sur les Risques, l'Environnement, la Mobilité et l'Aménagement (Cerema)-EDF R&D (EDF R&D), Centre Eau Terre Environnement [Québec] (INRS - ETE), and Institut National de la Recherche Scientifique [Québec] (INRS)
Subjects: Stratigraphy, 0207 environmental engineering, 02 engineering and technology, 010501 environmental sciences, 01 natural sciences, Numerical modeling, Gironde estuary, 14. Life underwater, Turbidity, [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces, environment, 020701 environmental engineering, Squat effect, 0105 earth and related environmental sciences, Hydrology, geography, geography.geographical_feature_category, Consolidation (soil), Discharge, [SPI.FLUID]Engineering Sciences [physics]/Reactive fluid environment, Estuary, Geology, Dimensional modeling, Sediment transport, Opentelemac, Gironde, 13. Climate action, Environmental science, Mixed sediment
Abstract: International audience; In order to optimize ship navigation in the macrotidal Gironde Estuary, a recent project funded by the port of Bordeaux aims at better understand and forecast hydrodynamic and fine sediment transport within the estuary. In the framework of this project, a two-dimensional hydro-sedimentary model is built. The model includes hydrodynamic forcings, mixed-sediment transport, and consolidation processes. The harmonic analysis of the astronomical tides reveals a strong distortion of the tidal wave inducing the growth of overtide constituents and the non-significant effect of tide-surge interactions in annual-scale prediction. Depending on hydrological conditions, river discharge can considerably alter the model accuracy due to the migration of the turbidity maximum zone modifying the bottom roughness. Comparison with measurements shows the ability of the model to reproduce suspended-sediment concentrations in the central Estuary. Sensitivity of the model to sediment features has also been discussed in regard of suspended-sediment concentrations and fluid mud deposits. The model will be further coupled with ship squat predictions and a morphodynamic model.p { margin-bottom: 0.25 cm; line-height: 115%; }
Published: 2021

8. Nonlinear time‐domain wave‐structure interaction: A parallel fast integral equation approach

Author: Michel Benoit, Jeffrey C. Harris, Stephan T. Grilli, Emmanuel Dombre, Konstantin Kuznetsov, École des Ponts ParisTech (ENPC), Laboratoire d'Hydraulique Saint-Venant / Saint-Venant laboratory for Hydraulics (Saint-Venant), École des Ponts ParisTech (ENPC)-Centre d'Etudes et d'Expertise sur les Risques, l'Environnement, la Mobilité et l'Aménagement (Cerema)-EDF R&D (EDF R&D), EDF (EDF)-EDF (EDF), Laboratoire National d’Hydraulique et Environnement (EDF R&D LNHE), EDF R&D (EDF R&D), Institut de Recherche sur les Phénomènes Hors Equilibre (IRPHE), Centre National de la Recherche Scientifique (CNRS)-Aix Marseille Université (AMU)-École Centrale de Marseille (ECM), University of Rhode Island (URI), Laboratoire d'Hydraulique Saint-Venant / Saint-Venant laboratory for Hydraulics (LHSV), École des Ponts ParisTech (ENPC)-EDF R&D (EDF R&D), and Aix Marseille Université (AMU)-École Centrale de Marseille (ECM)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Physics, [SDE.IE]Environmental Sciences/Environmental Engineering, Applied Mathematics, Mechanical Engineering, Mathematical analysis, Computational Mechanics, 01 natural sciences, Integral equation, 010305 fluids & plasmas, Computer Science Applications, Physics::Fluid Dynamics, 010101 applied mathematics, Nonlinear system, Mechanics of Materials, Free surface, 0103 physical sciences, Fluid–structure interaction, Potential flow, Time domain, 0101 mathematics, Multipole expansion, Boundary element method
Abstract: International audience; We report on the development and validation of a new Numerical Wave Tank (NWT) solving fully nonlinear potential flow (FNPF) equations, as a more efficient variation of Grilli et al.'s NWT [Grilli et al., A fully nonlinear model for three-dimensional overturning waves over arbitrary bottom, International Journal for Numerical Methods in Fluids 35 (2001) 829-867], which was successful at modeling many wave phenomena, including landslide-generated tsunamis, rogue waves, and the initiation
Published: 2021

9. Drag coefficient Uncertainty for floating wind turbines

Author: Robaux, Fabien, Nadal, Adria, Peyrard, Christophe, Benoit, Michel, Benguigui, William, Guiton, Martin, Laboratoire d'Hydraulique Saint-Venant / Saint-Venant laboratory for Hydraulics (LHSV), École des Ponts ParisTech (ENPC)-Centre d'Etudes et d'Expertise sur les Risques, l'Environnement, la Mobilité et l'Aménagement (Cerema)-EDF R&D (EDF R&D), EDF (EDF)-EDF (EDF), Laboratoire National d’Hydraulique et Environnement (EDF R&D LNHE), EDF R&D (EDF R&D), IFP Energies nouvelles (IFPEN), Mécanique des Fluides, Energies et Environnement (EDF R&D MFEE), Institut des Sciences de la mécanique et Applications industrielles (IMSIA - UMR 9219), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-École Nationale Supérieure de Techniques Avancées (ENSTA Paris)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-EDF R&D (EDF R&D), and European Project: 101006689,HIPERWIND
Subjects: [SDE.IE]Environmental Sciences/Environmental Engineering
Abstract: International audience
Published: 2022

10. A possible strong impact of tidal power plant on silver eels' migration

Author: Thomas Trancart, Nils Teichert, Jézabel Lamoureux, Elouana Gharnit, Anthony Acou, Eric De Oliveira, Romain Roy, Eric Feunteun, Biologie des Organismes et Ecosystèmes Aquatiques (BOREA), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-Muséum national d'Histoire naturelle (MNHN)-Institut de Recherche pour le Développement (IRD)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université des Antilles (UA), Station marine Dinard, Centre De Recherche et d'Enseignement sur les Systèmes Côtiers (CRESCO), Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER), Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER), Patrimoine naturel (PatriNat), Muséum national d'Histoire naturelle (MNHN)-Centre National de la Recherche Scientifique (CNRS)-Office français de la biodiversité (OFB), Laboratoire National d’Hydraulique et Environnement (EDF R&D LNHE), EDF R&D (EDF R&D), and EDF (EDF)-EDF (EDF)
Subjects: Conservation policy, Tidal power plant, Hydropower plant, Turbines, [SDV.BA.ZV]Life Sciences [q-bio]/Animal biology/Vertebrate Zoology, Anguilla Anguilla, Acoustic telemetry, Aquatic Science, [SDE.BE]Environmental Sciences/Biodiversity and Ecology, Oceanography, Escapement
Abstract: International audience; Very few tidal power plants exist in the world. The first one was built in the Rance estuary (Brittany, France) in 1966 and the second one in South Korea. However, with the increasing demand in renewable energy, other tidal power plant projects are being studied. These power plants are larger than unidirectional fluvial hydropower plants and strongly modify the natural tidal cycle in estuarine systems. As such, their effect on megafaunal movements might strongly differ from those caused by unidirectional fluvial hydropower plants and should be specifically considered and studied before the development of similar constructions. In this study, an acoustic telemetry array was deployed to track 25 silver eels released 16 km upstream of the Rance tidal power dam. Only 1/3 of the tagged eels passed the dam and reached the sea. Data suggested that eels interrupted their migration up to 5 km upstream of the dam. We assume that the noise and tidal disturbance generated by the dam could lead to a disruption of a high proportion of silver eels' reproductive migration.
Published: 2022

11. Direct habitat descriptors improve the understanding of the organization of fish and macroinvertebrate communities across a large catchment

Author: Coline Picard, Mathieu Floury, Hanieh Seyedhashemi, Maxime Morel, Hervé Pella, Nicolas Lamouroux, Laëtitia Buisson, Florentina Moatar, Anthony Maire, Laboratoire National d’Hydraulique et Environnement (EDF R&D LNHE), EDF R&D (EDF R&D), EDF (EDF)-EDF (EDF), RiverLy - Fonctionnement des hydrosystèmes (RiverLy), Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Laboratoire d'Ecologie des Hydrosystèmes Naturels et Anthropisés (LEHNA), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-École Nationale des Travaux Publics de l'État (ENTPE)-Centre National de la Recherche Scientifique (CNRS), GéoHydrosystèmes COntinentaux (GéHCO EA6293), Université de Tours (UT), Laboratoire Ecologie Fonctionnelle et Environnement (LEFE), Institut Ecologie et Environnement (INEE), Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), and Université de Toulouse (UT)
Subjects: Multidisciplinary, Freshwater fish, Fishes, Water, Surface water, Invertebrates, Habitats, Fish, Rivers, [SDE]Environmental Sciences, Animals, Community ecology, [SDE.BE]Environmental Sciences/Biodiversity and Ecology, Fish biology, Estuaries, Ecosystem, Environmental Monitoring
Abstract: In large-scale aquatic ecological studies, direct habitat descriptors (e.g. water temperature, hydraulics in river reaches) are often approximated by coarse-grain surrogates (e.g. air temperature, discharge respectively) since they are easier to measure or model. However, as biological variability can be very strong at the habitat scale, surrogate variables may have a limited ability to capture all of this variability, which may lead to a lesser understanding of the ecological processes or patterns of interest. In this study, we aimed to compare the capacity of direct habitat descriptors vs. surrogate environmental variables to explain the organization of fish and macroinvertebrate communities across the Loire catchment in France (105 km2). For this purpose, we relied on high-resolution environmental data, extensive biological monitoring data (>1000 sampling stations) and multivariate analyses. Fish and macroinvertebrate abundance datasets were considered both separately and combined to assess the value of a cross-taxa approach. We found that fish and macroinvertebrate communities exhibited weak concordance in their organization and responded differently to the main ecological gradients. Such variations are probably due to fundamental differences in their life-history traits and mobility. Regardless of the biological group considered, direct habitat descriptors (water temperature and local hydraulic variables) consistently explained the organization of fish and macroinvertebrate communities better than surrogate descriptors (air temperature and river discharge). Furthermore, the organization of fish and macroinvertebrate communities was slightly better explained by the combination of direct or surrogate environmental variables when the two biological groups were considered together than when considered separately. Tied together, these results emphasize the importance of using a cross-taxa approach in association with high-resolution direct habitat variables to more accurately explain the organization of aquatic communities.
Published: 2022

12. Optimization of the geopotential heights information used in a rainfall-based weather patterns classification over Austria

Author: Pierre Brigode, Pierre Ribstein, Pietro Bernardara, Federico Garavaglia, Ralf Merz, Joël Gailhard, Laboratoire National d’Hydraulique et Environnement (EDF R&D LNHE), EDF R&D (EDF R&D), EDF (EDF)-EDF (EDF), Structure et fonctionnement des systèmes hydriques continentaux (SISYPHE), Université Pierre et Marie Curie - Paris 6 (UPMC)-École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-MINES ParisTech - École nationale supérieure des mines de Paris, Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS), EDF DTG DMM, EDF (EDF), Department of Catchment Hydrology [UFZ Leipzig], Helmholtz Zentrum für Umweltforschung = Helmholtz Centre for Environmental Research (UFZ), Bourse CIFRE entre le Laboratoire National d'Hydraulique et d'Environnement (LNHE) d'EDF R&D et l'UMR 7619 SISYPHE, Université Pierre et Marie Curie, Université Pierre et Marie Curie - Paris 6 (UPMC)-École Pratique des Hautes Études (EPHE), and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Mines Paris - PSL (École nationale supérieure des mines de Paris)
Subjects: Atmospheric Science, Geopotential, 010504 meteorology & atmospheric sciences, Meteorology, Atmospheric circulation, [SDE.MCG]Environmental Sciences/Global Changes, 0207 environmental engineering, Bottom-up classification, 02 engineering and technology, 01 natural sciences, Austrian heavy rainfall, Position (vector), Physical information, Daily precipitation shape fields, COST733, 020701 environmental engineering, Spatial description, 0105 earth and related environmental sciences, 13. Climate action, [SDU.STU.CL]Sciences of the Universe [physics]/Earth Sciences/Climatology, Climatology, Weather patterns, Geopotential height field, Environmental science, Spatial extent
Abstract: Classifications of atmospheric circulation patterns are useful tools to improve the description of the climate of a given region and the analysis of meteorological situations. In particular, weather pattern (WP) classifications could be used to improve the description of spatial heavy rainfall. Here, a bottom-up approach, previously used to build WP classification in France, is applied for the definition of a WP classification useful for the description of Austrian heavy rainfall. The optimal spatial extent and the optimal position of the geopotential fields to be taken into account for a WP classification is studied. The proposed WP classification is shown to be coherent with the general knowledge on synoptic situations responsible for heavy rainfall over Austria. Moreover, the classification has good performances in terms of heavy rainfall spatial description compared to 152 COST 733 classifications defined in the same region. In particular, we show that the choice of spatial extent of the geopotential fields, their position and their characteristics is relevant for capturing physical information on synoptic situations responsible for heavy rainfall and that it can improve WP classification performances. Copyright © 2012 Royal Meteorological Society
Published: 2012

13. HABBY : A New Open-Source Software to Estimate Hydraulic Habitat Suitability

Author: Royer, Quentin, Gunten, Diane, Le Coarer, Yann, Lamouroux, Nicolas, Capra, Hervé, Sagnes, Pierre, Zaoui, Fabrice, Risques, Ecosystèmes, Vulnérabilité, Environnement, Résilience (RECOVER), Aix Marseille Université (AMU)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), RiverLy - Fonctionnement des hydrosystèmes (RiverLy), Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Office français de la biodiversité - Pôle Ecohydraulique OFB - IMFT - P' (Pôle écohydraulique OFB - IMFT - P'), Institut de mécanique des fluides de Toulouse (IMFT), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Institut Pprime (PPRIME), Université de Poitiers-ENSMA-Centre National de la Recherche Scientifique (CNRS)-Université de Poitiers-ENSMA-Centre National de la Recherche Scientifique (CNRS)-Office français de la biodiversité (OFB), Université de Toulouse (UT), Laboratoire National d’Hydraulique et Environnement (EDF R&D LNHE), EDF R&D (EDF R&D), EDF (EDF)-EDF (EDF), and zaoui, fabrice
Subjects: [SDE.BE] Environmental Sciences/Biodiversity and Ecology, Hydraulic models, Ecohydraulics, [SDE.BE]Environmental Sciences/Biodiversity and Ecology, Fish and Invertebrate, Ecological flow, Habitat modelling
Abstract: International audience; The life of aquatic fauna in streams and rivers depends on hydrological variability with considerable emphasis on minimum discharge in flow regulated reaches. One of the methods used to define ecologically suitable minimum discharges is the physical habitat simulation method (habitat model) which converts the outputs of a hydrodynamic river model into habitat suitability for different aquatic taxa, based on their estimated hydraulic preferences. The application of this method requires the use of dedicated software. One of the current computer programs for habitat simulations in France (EVHA) is not technically up-to-date and had to be replaced. Much more than an update of existing software, HABBY is a new free and open-source program, which will be very useful to estimate ecological flows through aquatic habitat availability and suitability. Compatible with MS-Windows, macOS, and GNU/Linux, HABBY is developed in Python. It does not contain any internal hydrodynamic model but accepts, as inputs, the output files of several commonly used models. It also incorporates three statistical habitat models, including Estimhab, a popular statistical model in France. Moreover, a system of scripts helps to store past studies and facilitates the implementation of complex case studies.
Published: 2022

14. SPH simulation of the 2007 Chehalis Lake landslide and subsequent tsunami

Author: Philip L.-F. Liu, Alex Ghaïtanellis, Thomas Viard, Damien Violeau, Laboratoire National d’Hydraulique et Environnement (EDF R&D LNHE), EDF R&D (EDF R&D), and EDF (EDF)-EDF (EDF)
Subjects: 0208 environmental biotechnology, Landslide, 02 engineering and technology, 01 natural sciences, Physics::Geophysics, 010305 fluids & plasmas, 020801 environmental engineering, Condensed Matter::Soft Condensed Matter, Smoothed-particle hydrodynamics, 0103 physical sciences, Geotechnical engineering, [PHYS.MECA.MEFL]Physics [physics]/Mechanics [physics]/Fluid mechanics [physics.class-ph], ComputingMilieux_MISCELLANEOUS, Geology, Water Science and Technology, Civil and Structural Engineering
Abstract: A multi-phase smoothed particle hydrodynamics (SPH) formulation in combination with a granular rheological model is applied to simulate the 2007 Chehalis Lake landslide and the subsequent tsunami. ...
Published: 2021

15. Etude de sensibilité globale comparée des modèles hydrologiques GRP et MORDOR-TS

Author: Anne-Laure Tiberi-Wadier, Nicole Goutal, Sophie Ricci, Philippe Sergent, Julie Viatgé, Céline Monteil, François Bouttier, Centre d'Etudes et d'Expertise sur les Risques, l'Environnement, la Mobilité et l'Aménagement - Equipe-projet HA (Cerema Equipe-projet HA), Centre d'Etudes et d'Expertise sur les Risques, l'Environnement, la Mobilité et l'Aménagement (Cerema), Laboratoire d'Hydraulique Saint-Venant / Saint-Venant laboratory for Hydraulics (LHSV), Avant création Cerema, Centre d'Etudes et d'Expertise sur les Risques, l'Environnement, la Mobilité et l'Aménagement - Direction Eau Mer et Fleuves (Cerema Direction Eau Mer et Fleuves), Hydrosystèmes continentaux anthropisés : ressources, risques, restauration (UR HYCAR), Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Laboratoire National d’Hydraulique et Environnement (EDF R&D LNHE), EDF R&D (EDF R&D), EDF (EDF)-EDF (EDF), Centre national de recherches météorologiques (CNRM), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), and Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS)
Subjects: [SDU.STU.ME]Sciences of the Universe [physics]/Earth Sciences/Meteorology, [SDU.STU.HY]Sciences of the Universe [physics]/Earth Sciences/Hydrology, ComputingMilieux_MISCELLANEOUS
Abstract: International audience
Published: 2021

16. Bypass discharge, approach velocities and bar spacing: the three key-parameters to efficiently protect silver eels with inclined racks

Author: Sylvie Tomanova, Laurence Tissot, Stéphane Tétard, Sylvain Richard, Olivier Mercier, Vincent Mataix, Aurélien Frey, Thierry Lagarrigue, Pablo A. Tedesco, Dominique Courret, Office français de la biodiversité - Pôle Ecohydraulique OFB - IMFT - P' (Pôle écohydraulique OFB - IMFT - P'), Institut de mécanique des fluides de Toulouse (IMFT), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Institut Pprime (PPRIME), Université de Poitiers-ENSMA-Centre National de la Recherche Scientifique (CNRS)-Université de Poitiers-ENSMA-Centre National de la Recherche Scientifique (CNRS)-Office français de la biodiversité (OFB), Université de Toulouse (UT), Laboratoire National d’Hydraulique et Environnement (EDF R&D LNHE), EDF R&D (EDF R&D), EDF (EDF)-EDF (EDF), ICEO Environnement, EDF CIH, Etudes et Conseils en Gestion de l'Environnement Aquatique - ECOGEA (FRANCE), Evolution et Diversité Biologique (EDB), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), and Université de Toulouse (UT)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Ecology, surface bypass, Hydropower plant, downstream passage, [PHYS.MECA.MEFL]Physics [physics]/Mechanics [physics]/Fluid mechanics [physics.class-ph], Management, Monitoring, Policy and Law, Aquatic Science, fish protection, Nature and Landscape Conservation, Water Science and Technology
Abstract: Hydropower energy can contribute to achieve the carbon neutrality goals, but also needs to reach environmental sustainability. Hydropower plants (HPP) constitute barriers to fish migrations that are essential for accomplishing their complete biological cycle. Fish downstream passage solutions (FDPS) have to be implemented to maximize their survival, guiding them away from the turbine intakes towards a safe passage alternative. Recent telemetry studies confirmed the efficiency of 26° inclined low bar spacing (20 mm) rack associated to surface bypasses, installed upstream HPPs, to protect downstream migrating Atlantic salmon smolts. Here we tested the efficiency of such FDPS for eel protection using radiotelemetry at four successive HPPs (with intake capacities from 28 to 45 m3.s−1) in the Ariège River (southern France). Between 52 and 74 eels, longer than 550 mm, entered the HPP intakes and 100% of them were protected from turbine passage. All eels crossed the HPP water intake using the surface bypasses, and the great majority in few minutes from their first presentation in front of the rack. These results showed that in such rack configuration, it is not necessary to add a specific bottom bypass, usually recommended for eels. We also showed the importance of optimal hydraulic conditions, mainly tangential (parallel to the rack) velocity and bypass discharge, to efficiently guide the eels towards the surface bypasses, reducing their passage time. Overall, our study provided key elements to water managers for designing an efficient FDPS for eels.
Published: 2023

17. A comparison of process synthesis approaches for multistage separation processes by gas permeation

Author: Thibaut Neveux, Bernardetta Addis, Christophe Castel, Veronica Piccialli, Eric Favre, Laboratoire National d’Hydraulique et Environnement (EDF R&D LNHE), EDF R&D (EDF R&D), EDF (EDF)-EDF (EDF), Laboratoire Lorrain de Recherche en Informatique et ses Applications (LORIA), Institut National de Recherche en Informatique et en Automatique (Inria)-Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Réactions et Génie des Procédés (LRGP), Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS), Università degli Studi di Roma Tor Vergata [Roma], Montastruc, Ludovic and Negny, Stéphane, OPTImisation Methods for Integrated SysTems (OPTIMIST), Department of Networks, Systems and Services (LORIA - NSS), Institut National de Recherche en Informatique et en Automatique (Inria)-Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS)-Laboratoire Lorrain de Recherche en Informatique et ses Applications (LORIA), and Institut National de Recherche en Informatique et en Automatique (Inria)-Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS)
Subjects: [CHIM.GENI]Chemical Sciences/Chemical engineering, confInternatₐcte, [SPI.GPROC]Engineering Sciences [physics]/Chemical and Process Engineering
Abstract: 10.1016/B978-0-323-95879-0.50115-6; International audience
Published: 2022

18. A functional vulnerability framework for biodiversity conservation

Author: Arnaud Auber, Conor Waldock, Anthony Maire, Eric Goberville, Camille Albouy, Adam C. Algar, Matthew McLean, Anik Brind’Amour, Alison L. Green, Mark Tupper, Laurent Vigliola, Kristin Kaschner, Kathleen Kesner-Reyes, Maria Beger, Jerry Tjiputra, Aurèle Toussaint, Cyrille Violle, Nicolas Mouquet, Wilfried Thuiller, David Mouillot, Laboratoire Ressources halieutiques Boulogne sur mer (LRHBL), Halieutique Manche Mer du Nord (HMMN), Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER), Landscape Ecology Group [ETH Zürich], Institute of Terrestrial Ecosystems (ITES), Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich)- Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich), Laboratoire National d’Hydraulique et Environnement (EDF R&D LNHE), EDF R&D (EDF R&D), EDF (EDF)-EDF (EDF), Biologie des Organismes et Ecosystèmes Aquatiques (BOREA), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-Muséum national d'Histoire naturelle (MNHN)-Institut de Recherche pour le Développement (IRD)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université des Antilles (UA), Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER), ARC Centre of Excellence for Coral Reef Studies (CoralCoE), James Cook University (JCU), Ecologie marine tropicale des océans Pacifique et Indien (ENTROPIE [Nouvelle-Calédonie]), Institut de Recherche pour le Développement (IRD [Nouvelle-Calédonie])-Ifremer - Nouvelle-Calédonie, Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Université de la Nouvelle-Calédonie (UNC), Department of Biometry and Environmental System Analysis, Albert-Ludwigs-Universität Freiburg, University of Leeds, University of Queensland [Brisbane], Bjerknes Centre for Climate Research (BCCR), Department of Biological Sciences [Bergen] (BIO / UiB), University of Bergen (UiB)-University of Bergen (UiB), Institute of Ecology and Earth Sciences [Tartu], University of Tartu, Centre d’Ecologie Fonctionnelle et Evolutive (CEFE), Université Paul-Valéry - Montpellier 3 (UPVM)-École Pratique des Hautes Études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud])-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut Agro Montpellier, Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Université de Montpellier (UM), Fondation pour la recherche sur la Biodiversité (FRB), MARine Biodiversity Exploitation and Conservation (UMR MARBEC), Institut de Recherche pour le Développement (IRD)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM), Laboratoire d'Ecologie Alpine (LECA ), and Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)
Subjects: Mammals, Conservation of Natural Resources, Multidisciplinary, Ecology, [SDE.MCG]Environmental Sciences/Global Changes, Fishes, General Physics and Astronomy, Biodiversity, General Chemistry, General Biochemistry, Genetics and Molecular Biology, FOS: Biological sciences, Animals, 570 Life sciences, biology, Community ecology, [SDE.BE]Environmental Sciences/Biodiversity and Ecology, Ecological modelling, Ecosystem
Abstract: Setting appropriate conservation strategies in a multi-threat world is a challenging goal, especially because of natural complexity and budget limitations that prevent effective management of all ecosystems. Safeguarding the most threatened ecosystems requires accurate and integrative quantification of their vulnerability and their functioning, particularly the potential loss of species trait diversity which imperils their functioning. However, the magnitude of threats and associated biological responses both have high uncertainties. Additionally, a major difficulty is the recurrent lack of reference conditions for a fair and operational measurement of vulnerability. Here, we present a functional vulnerability framework that incorporates uncertainty and reference conditions into a generalizable tool. Through in silico simulations of disturbances, our framework allows us to quantify the vulnerability of communities to a wide range of threats. We demonstrate the relevance and operationality of our framework, and its global, scalable and quantitative comparability, through three case studies on marine fishes and mammals. We show that functional vulnerability has marked geographic and temporal patterns. We underline contrasting contributions of species richness and functional redundancy to the level of vulnerability among case studies, indicating that our integrative assessment can also identify the drivers of vulnerability in a world where uncertainty is omnipresent., Nature Communications, 13 (1), ISSN:2041-1723
Published: 2022

19. Invasion impacts and dynamics of a European‐wide introduced species

Author: Phillip J. Haubrock, Danish A. Ahmed, Ross N. Cuthbert, Rachel Stubbington, Sami Domisch, Jaime R. G. Marquez, Ayah Beidas, Giuseppe Amatulli, Jens Kiesel, Longzhu Q. Shen, Ismael Soto, David G. Angeler, Núria Bonada, Miguel Cañedo‐Argüelles, Zoltán Csabai, Thibault Datry, Elvira de Eyto, Alain Dohet, Emma Drohan, Judy England, Maria J. Feio, Marie A. E. Forio, Peter Goethals, Wolfram Graf, Jani Heino, Emma J. Hudgins, Sonja C. Jähnig, Richard K. Johnson, Aitor Larrañaga, Patrick Leitner, Lionel L'Hoste, Marie‐Helene Lizee, Anthony Maire, Jes J. Rasmussen, Ralf B. Schäfer, Astrid Schmidt‐Kloiber, Rudy Vannevel, Gábor Várbíró, Peter Wiberg‐Larsen, Peter Haase, Senckenberg Research Institute and Natural History Museum [Frankfurt], Senckenberg – Leibniz Institution for Biodiversity and Earth System Research - Senckenberg Gesellschaft für Naturforschung, Leibniz Association-Leibniz Association, University of South Bohemia, RiverLy - Fonctionnement des hydrosystèmes (RiverLy), Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Freshwater Centre [Helsinki], Finnish Environment Institute (SYKE), Risques, Ecosystèmes, Vulnérabilité, Environnement, Résilience (RECOVER), Aix Marseille Université (AMU)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Laboratoire National d’Hydraulique et Environnement (EDF R&D LNHE), EDF R&D (EDF R&D), EDF (EDF)-EDF (EDF), Bundesministerium für Bildung und Forschung, Grant/Award Number: 033W034A, Kuwait Foundation for the Advancement of Sciences, Grant/Award Number: PR1914SM- 01Leibniz Competition, Grant/Award Number: J45/2018, Leverhulme Trust, Grant/Award Number: ECF-2021- 001, Alexander von Humboldt Foundation, Gulf University for Science and Technology (GUST), Grant/Award Number: 234597 and 253536, European Project: 871128,eLTER PLUS (2020), Suomen ympäristökeskus, and The Finnish Environment Institute
Subjects: vaeltajakotilo, vaikutukset, [SDE.MCG]Environmental Sciences/Global Changes, Snails, biological invasion, temporal modelling, RESEARCH ARTICLES, RESEARCH ARTICLE, NEW-ZEALAND MUDSNAILS, BIOLOGICAL INVASIONS, MOLLUSK, Animals, Environmental Chemistry, rapid response, Potamopyrgus antipodarum, vieraslajit, PLASTICITY, Eurooppa, early detection, Ecosystem, rapid response/early detection, General Environmental Science, Global and Planetary Change, Ecology, SUCCESS, FRAMEWORK, populaatiodynamiikka, long‐term time series, Europe, COMMUNITY, long-term time series, POTAMOPYRGUS-ANTIPODARUM HYDROBIIDAE, eläinekologia, Earth and Environmental Sciences, [SDE]Environmental Sciences, SPREAD, ZABR, [SDE.BE]Environmental Sciences/Biodiversity and Ecology, Introduced Species, Biologie, leviäminen, New Zealand, RESPONSES
Abstract: International audience; Globalization has led to the introduction of thousands of alien species worldwide. With growing impacts by invasive species, understanding the invasion process remains critical for predicting adverse effects and informing efficient management. Theoretically, invasion dynamics have been assumed to follow an "invasion curve" (S-shaped curve of available area invaded over time), but this dynamic has lacked empirical testing using large-scale data and neglects to consider invader abundances. We propose an "impact curve" describing the impacts generated by invasive species over time based on cumulative abundances. To test this curve's large-scale applicability, we used the data-rich New Zealand mud snail Potamopyrgus antipodarum, one of the most damaging freshwater invaders that has invaded almost all of Europe. Using long-term (1979-2020) abundance and environmental data collected across 306 European sites, we observed that P. antipodarum abundance generally increased through time, with slower population growth at higher latitudes and with lower runoff depth. Fifty-nine percent of these populations followed the impact curve, characterized by first occurrence, exponential growth, then long-term saturation. This behaviour is consistent with boom-bust dynamics, as saturation occurs due to a rapid decline in abundance over time. Across sites, we estimated that impact peaked approximately two decades after first detection, but the rate of progression along the invasion process was influenced by local abiotic conditions. The S-shaped impact curve may be common among many invasive species that undergo complex invasion dynamics. This provides a potentially unifying approach to advance understanding of large-scale invasion dynamics and could inform timely management actions to mitigate impacts on ecosystems and economies.
Published: 2022

20. Simulating wave overtopping on a complex coastal structure using SPH

Author: Damien Violeau, Agnès Leroy, Athanasios Mokos, Remi Carmigniani, Laboratoire National d’Hydraulique et Environnement (EDF R&D LNHE), EDF R&D (EDF R&D), and EDF (EDF)-EDF (EDF)
Subjects: business.industry, Wave propagation, Astrophysics::Instrumentation and Methods for Astrophysics, Structure (category theory), Regular wave, Astrophysics::Cosmology and Extragalactic Astrophysics, Mechanics, Computational fluid dynamics, 01 natural sciences, 010305 fluids & plasmas, Physics::Fluid Dynamics, 010101 applied mathematics, Smoothed-particle hydrodynamics, 0103 physical sciences, Meshfree methods, Coastal engineering, [PHYS.MECA.MEFL]Physics [physics]/Mechanics [physics]/Fluid mechanics [physics.class-ph], Astrophysics::Earth and Planetary Astrophysics, 0101 mathematics, business, ComputingMilieux_MISCELLANEOUS, Astrophysics::Galaxy Astrophysics, Geology, Water Science and Technology, Wave simulation
Abstract: This paper investigates the applicability of Smoothed Particle Hydrodynamics (SPH) for regular wave overtopping. The best practices for creating a 3-D wave simulation using SPH are investigated, fo...
Published: 2020

21. Determination of monochloramine dissipation kinetics in various surface water qualities under relevant environmental conditions - Consequences regarding environmental risk assessment

Author: Bertille Richard-Tanaka, Adrien Roumiguières, Aziz Kinani, Michael Merklinger, Franck Marolleau, Said Kinani, Pia Gerstner, Stephany Layousse, Astrid Thoma, Riadh Ata, Stéphane Bouchonnet, Frank Sacher, DVGW-Technologiezentrum Wasser (TZW), Deutsche Verein des Gas- und Wasserfaches (DVGW), Laboratoire National d’Hydraulique et Environnement (EDF R&D LNHE), EDF R&D (EDF R&D), EDF (EDF)-EDF (EDF), Laboratoire de chimie moléculaire (LCM), and Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-École polytechnique (X)
Subjects: Environmental Engineering, 010504 meteorology & atmospheric sciences, Lag, Kinetics, Extrapolation, Sampling (statistics), Sediment, 010501 environmental sciences, Dissipation, 01 natural sciences, Pollution, 6. Clean water, 13. Climate action, Environmental chemistry, Environmental Chemistry, Degradation (geology), Environmental science, [CHIM.OTHE]Chemical Sciences/Other, Waste Management and Disposal, Surface water, ComputingMilieux_MISCELLANEOUS, 0105 earth and related environmental sciences
Abstract: A total 190 experiments were performed to study the dissipation kinetics of monochloramine (NH2Cl, CAS no 10599-90-3) in surface water samples from six rivers (Loire, Rhone, Meuse, Garonne, Seine and Moselle) and an artificial reservoir (Mirgenbach), all located in France. Experiments were conducted in an open reactor, under relevant controlled environmental conditions. The impact of various parameters such as initial NH2Cl concentration, temperature, pH, presence of sediments, sampling site and collection period was investigated. It was found that NH2Cl dissipated rapidly without any lag phase, and that decay follows an apparent first-order kinetics (r2 > 0.99). Presence of sediment greatly accelerated decay. Half-lives were generally
Published: 2019

22. An innovative bivariate approach to detect joint temporal trends in environmental conditions: Application to large French rivers and diadromous fish

Author: Eric Sauquet, Bertrand Villeneuve, Stéphane Tétard, Hilaire Drouineau, Elorri Arevalo, Géraldine Lassalle, Patrick Lambert, Alexis Paumier, Anthony Maire, Ecosystèmes aquatiques et changements globaux (UR EABX), Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Laboratoire National d’Hydraulique et Environnement (EDF R&D LNHE), EDF R&D (EDF R&D), EDF (EDF)-EDF (EDF), Riverly (Riverly), and HYNES program (IRSTEA - EDF RD) -Electricite de France (EDF)
Subjects: Environmental Engineering, 010504 meteorology & atmospheric sciences, [SDE.MCG]Environmental Sciences/Global Changes, Context (language use), Bivariate analysis, 010501 environmental sciences, 01 natural sciences, Upstream and downstream (DNA), Trend analysis, [SDV.EE.ECO]Life Sciences [q-bio]/Ecology, environment/Ecosystems, Rivers, Diadromous species, Environmental Chemistry, Animals, Humans, Ecosystem, 14. Life underwater, Waste Management and Disposal, Global change, 0105 earth and related environmental sciences, Fish migration, Discharge, Fishes, Pollution, Multivariate analysis, 13. Climate action, Water temperature, Environmental science, Physical geography, Seasons, Environmental Monitoring
Abstract: International audience; Most key life-events of organisms are synchronized by complex interactions of several environmental cues to ensure optimal survival and growth of individuals and their offspring. However, global change is known to affect multiple components of ecosystems and cues at the same time. Therefore, detecting joint trends in covariate time series is a crucial challenge in global change ecology that has rarely been addressed so far. In this context, we designed an innovative combination of kernel density estimations and Mann-Kendall trend tests to detect joint temporal trends in a pair of environmental variables. This methodological framework was tested on >30 years (1976–2019) of water temperature and discharge data for 6 large French rivers (the Garonne, Dordogne, Rhône, Rhine, Loire and Vienne rivers). The implications of such trends in both temperature and discharge for diadromous species key life-cycle processes were then explored by checking if significant bivariate environmental changes occurred during seasons of upstream and downstream migration, and reproductive activities. Results were contrasted between rivers and seasons: many rivers displayed an increase in the number of days with high water temperature and low river discharge, but local discharge regulation measures could have mitigated the trend in discharge. Our findings showed that species migrating or spawning in spring were likely to be strongly impacted by the new environmental conditions in the Garonne, Loire and Rhône rivers, given the marked changes in water temperature and discharge associations detected by our new method. Conditions experienced by fall-running and spawning species have been strongly affected in all the rivers studied. This innovative methodology was implemented in a new R package, ChocR, for application to other environments and ecosystems.
Published: 2021

23. A Lossy Compression Experiment of Telemac Data

Author: Zaoui, Fabrice, Laboratoire National d’Hydraulique et Environnement (EDF R&D LNHE), EDF R&D (EDF R&D), EDF (EDF)-EDF (EDF), TELEMAC-MASCARET Core Group, and zaoui, fabrice
Subjects: [SDE] Environmental Sciences, [SDE]Environmental Sciences, Hydrodynamik (532.5), [INFO]Computer Science [cs], [INFO] Computer Science [cs]
Abstract: International audience; The Telemac-Mascaret system can require or produce large amount of data to address complex problems in geoscience or industry. This statement is verified with the availability of new databases and the increase of problem sizes solved by numerical simulation nowadays. But how to efficiently deal with such data when file sizes can range from several gigabytes to terabytes, or more? Dealing with a vast volume of data is not always possible. Copy, transfer or storage of large files can quickly become an issue to carry out a study in a short period of time. The high memory usage is mainly due to the double precision floating point representation of billions of real numbers, which can hardly be avoided except with doing a compromise between necessity and feasibility. For example, the latter can be the frequency of saving results in file which may differ from the calculation time step. In this paper, another compromise is presented. It is the possibility of reducing the insignificant part of the information by compressing the data with a lossy algorithm. The acceptance of a loss of accuracy may have meaning in view of the uncertainty present in data especially if it is linked to the definition of error values that cannot be exceeded. To this end, the lossy compressor SZ is tested on hydrodynamic data coming from very large Selafin files. This tool can highly decrease the size of the data with compression ratio values directly depending on the user's choice for the error bounds. Some limitations and perspectives of this experiment are also discussed. I.
Published: 2021

24. The Navier-Stokes system with temperature and salinity for free surface flows. Numerical scheme and validation

Author: Boittin, Léa, Bouchut, François, Bristeau, Marie-Odile, Mangeney, Anne, Sainte-Marie, Jacques, Souillé, Fabien, Numerical Analysis, Geophysics and Ecology (ANGE), Inria de Paris, Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria)-Laboratoire Jacques-Louis Lions (LJLL (UMR_7598)), Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP), Laboratoire Analyse et Mathématiques Appliquées (LAMA), Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Centre National de la Recherche Scientifique (CNRS)-Université Gustave Eiffel, Centre d'Etudes et d'Expertise sur les Risques, l'Environnement, la Mobilité et l'Aménagement - Direction Centre-Est (Cerema Direction Centre-Est), Centre d'Etudes et d'Expertise sur les Risques, l'Environnement, la Mobilité et l'Aménagement (Cerema), Laboratoire National d’Hydraulique et Environnement (EDF R&D LNHE), EDF R&D (EDF R&D), EDF (EDF)-EDF (EDF), The authors acknowledge the Inria Project Lab 'Algae in Silico' for its financial support. This research is also supported by the ERC SLIDEQUAKES ERC-CG-2013-PE10-617472., Sainte-Marie, Jacques, and Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité)
Subjects: Layer-averaged formulation, Free surface flows, Finite volume scheme, [PHYS.MECA.MEFL] Physics [physics]/Mechanics [physics]/Fluid mechanics [physics.class-ph], Variable density flows, [INFO.INFO-MO] Computer Science [cs]/Modeling and Simulation, [PHYS.MECA.MEFL]Physics [physics]/Mechanics [physics]/Fluid mechanics [physics.class-ph], [MATH.MATH-NA] Mathematics [math]/Numerical Analysis [math.NA], Navier-Stokes equations, [INFO.INFO-MO]Computer Science [cs]/Modeling and Simulation, [MATH.MATH-NA]Mathematics [math]/Numerical Analysis [math.NA]
Abstract: In this paper, we propose a numerical scheme for the layer-averaged Euler with variable density and the Navier-Stokes-Fourier systems presented in part I (Boittin et al., 2018). These systems model hydrostatic free surface flows with density variations. We show that the finite volume scheme presented is well balanced with regards to the steady state of the lake at rest and preserves the positivity of the water height. A maximum principle on the density is also proved as well as a discrete entropy inequality in the case of the Euler system with variable density. Some numerical validations are finally shown with comparisons to 3D analytical solutions and experiments.
Published: 2021

25. Experimental and numerical characterization of swell type waves effect on wind sea growth with fetch

Author: Villefer, Antoine, Benoit, Michel, Violeau, Damien, Teles, Maria, Jeffreys, Harris, Branger, Hubert, Luneau, Christopher, Laboratoire d'Hydraulique Saint-Venant / Saint-Venant laboratory for Hydraulics (Saint-Venant), École des Ponts ParisTech (ENPC)-Centre d'Etudes et d'Expertise sur les Risques, l'Environnement, la Mobilité et l'Aménagement (Cerema)-EDF R&D (EDF R&D), EDF (EDF)-EDF (EDF), Laboratoire National d’Hydraulique et Environnement (EDF R&D LNHE), EDF R&D (EDF R&D), Institut de Recherche sur les Phénomènes Hors Equilibre (IRPHE), Centre National de la Recherche Scientifique (CNRS)-Aix Marseille Université (AMU)-École Centrale de Marseille (ECM), Institut Pythéas (OSU PYTHEAS), Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Branger, Hubert, Laboratoire d'Hydraulique Saint-Venant / Saint-Venant laboratory for Hydraulics (LHSV), and Aix Marseille Université (AMU)-École Centrale de Marseille (ECM)-Centre National de la Recherche Scientifique (CNRS)
Subjects: [SDU.OCEAN]Sciences of the Universe [physics]/Ocean, Atmosphere, [SDU.OCEAN] Sciences of the Universe [physics]/Ocean, Atmosphere, [PHYS.MECA.MEFL] Physics [physics]/Mechanics [physics]/Fluid mechanics [physics.class-ph], [PHYS.MECA.MEFL]Physics [physics]/Mechanics [physics]/Fluid mechanics [physics.class-ph], ComputingMilieux_MISCELLANEOUS
Abstract: International audience
Published: 2021

26. The dimensionality and structure of species trait spaces

Author: Brian J. McGill, Wilfried Thuiller, Cyrille Violle, Anthony Maire, David Mouillot, Maya Guéguen, Nicolas Casajus, Brian S. Maitner, Sébastien Villéger, Nicolas Loiseau, Pierre Denelle, Arnaud Auber, François Munoz, Marc W. Cadotte, Matthias Grenié, Adam C. Algar, Michele Allegra, Matthew McLean, Nicolas Mouquet, MARine Biodiversity Exploitation and Conservation (UMR MARBEC), Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Institut de Recherche pour le Développement (IRD), Institut de Recherche pour le Développement (IRD)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Centre d’Ecologie Fonctionnelle et Evolutive (CEFE), Université Paul-Valéry - Montpellier 3 (UPVM)-École Pratique des Hautes Études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud])-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut Agro - Montpellier SupAgro, Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro), Institut de Neurosciences de la Timone (INT), Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS), Centre de Synthèse et d’Analyse sur la Biodiversité (CESAB), Fondation pour la recherche sur la Biodiversité (FRB), Laboratoire d'Ecologie Alpine (LECA ), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA), Laboratoire National d’Hydraulique et Environnement (EDF R&D LNHE), EDF R&D (EDF R&D), EDF (EDF)-EDF (EDF), Laboratoire Interdisciplinaire de Physique [Saint Martin d’Hères] (LIPhy ), Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA), and Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)
Subjects: 0106 biological sciences, Ecology (disciplines), functional ecology, Biology, 010603 evolutionary biology, 01 natural sciences, species clustering, hypervolume, complexity, species uniqueness, Ecology, Phenotype, Research Design, Biodiversity, Ecosystem, Ecology, Evolution, Behavior and Systematics, ComputingMilieux_MISCELLANEOUS, Functional ecology, 010604 marine biology & hydrobiology, Robustness (evolution), 15. Life on land, Variable (computer science), Evolutionary biology, Trait, Species richness, [SDE.BE]Environmental Sciences/Biodiversity and Ecology, Curse of dimensionality, Global biodiversity
Abstract: Trait- based ecology aims to understand the processes that generate the overarching diversity of organismal traits and their influence on ecosystem functioning. Achieving this goal requires simplifying this complexity in synthetic axes defining a trait space and to cluster species based on their traits while identifying those with unique combinations of traits. However, so far, we know little about the dimensionality, the robustness to trait omission and the structure of these trait spaces. Here, we propose a unified framework and a synthesis across 30 trait datasets representing a broad variety of taxa, ecosystems and spatial scales to show that a common trade- off between trait space quality and operationality appears between three and six dimensions. The robustness to trait omission is generally low but highly variable among datasets. We also highlight invariant scaling relationships, whatever organismal complexity, between the number of clusters, the number of species in the dominant cluster and the number of unique species with total species richness. When species richness increases, the number of unique species saturates, whereas species tend to disproportionately pack in the richest cluster. Based on these results, we propose some rules of thumb to build species trait spaces and estimate subsequent functional diversity indices.
Published: 2021

27. Influence of swell on wind-wave growth with fetch: an experimental and numerical study

Author: Villefer, Antoine, Teles, Maria, Benoit, Michel, Violeau, Damien, Harris, Jeffrey C., Branger, Hubert, Laboratoire d'Hydraulique Saint-Venant / Saint-Venant laboratory for Hydraulics (Saint-Venant), École des Ponts ParisTech (ENPC)-Centre d'Etudes et d'Expertise sur les Risques, l'Environnement, la Mobilité et l'Aménagement (Cerema)-EDF R&D (EDF R&D), EDF (EDF)-EDF (EDF), Laboratoire National d’Hydraulique et Environnement (EDF R&D LNHE), EDF R&D (EDF R&D), Institut de Recherche sur les Phénomènes Hors Equilibre (IRPHE), Centre National de la Recherche Scientifique (CNRS)-Aix Marseille Université (AMU)-École Centrale de Marseille (ECM), Laboratoire d'Hydraulique Saint-Venant / Saint-Venant laboratory for Hydraulics (LHSV), and Aix Marseille Université (AMU)-École Centrale de Marseille (ECM)-Centre National de la Recherche Scientifique (CNRS)
Subjects: [SDU.OCEAN]Sciences of the Universe [physics]/Ocean, Atmosphere, [PHYS.MECA.MEFL]Physics [physics]/Mechanics [physics]/Fluid mechanics [physics.class-ph], ComputingMilieux_MISCELLANEOUS
Abstract: International audience
Published: 2021

28. Trend of stream temperature and its drivers over the past 55 years in a large European River basin

Author: Florentina Moatar, Céline Monteil, Dominique Thiéry, Hanieh Seyedhashemi, Jean-Philippe Vidal, Frédéric Hendrickx, Riverly (Riverly), Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), GéoHydrosystèmes COntinentaux (GéHCO EA6293), Université de Tours, Bureau de Recherches Géologiques et Minières (BRGM) (BRGM), Laboratoire National d’Hydraulique et Environnement (EDF R&D LNHE), EDF R&D (EDF R&D), EDF (EDF)-EDF (EDF), and Université de Tours (UT)
Subjects: Hydrology, geography, geography.geographical_feature_category, 13. Climate action, Drainage basin, Environmental science, [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces, environment, Stream temperature
Abstract: Air temperature has been increasing all around the world over the past decades. Owing to its sensitivity to air temperature, it is consequently expected that stream temperature experiences an increase as well. However, due to paucity of long-term stream temperature data, assessments of the magnitude of such trends in relation with landscape and hydrological changes have remained scarce.The present study used a physically-based thermal model (T-NET: Temperature-NETwork), coupled with a semi-distributed hydrological model (EROS) to reconstruct past daily stream temperatures and discharges at the scale of the Loire River basin in France (105 km2 with 52278 reaches). The ability of both models to reconstruct long-term trends was assessed at 44 gauging stations and 11 stream temperature stations. T-NET simulations over the 1963-2017 period show that there has been a significant increasing trend in stream temperatures for at least 70% of reaches in all seasons (median=0.36 °C/decade). Significantly increasing trends are more prominent in spring (Mar-May) and summer (Jun-Aug) with a median increase of 0.37 °C (0.11 to 0.8°C) and 0.42°C (0.14 to 1 °C) per decade, respectively. For 81 % of reaches, annual stream temperature trends are greater than annual air temperature trends (median ratio=1.21; interquartile ranges: 1.06-1.44). Greater increases in stream temperature in spring and summer are found in the south of the basin, mostly in the Massif Central (up to 1°C/decade) where greater increase in air temperature (up to 0.67 °C/decade) and greater decrease in discharge (up to -16%/decade) occur jointly. The increase of stream temperature is also higher in large rivers compared to small rivers where riparian vegetation shading mitigate the increase in temperature. For the majority of reaches, changes in stream temperature, air temperature, and discharge significantly intensified in the late 1980s.These climate-induced changes in the annual and seasonal stream temperature could help us to explain shifts in the phenology and geographical distribution of cold-water fish especially in the south of the basin where trends are more pronounced.
Published: 2021

29. Joint temporal trends in river thermal and hydrological conditions can threaten the downstream migration of the critically endangered European eel

Author: Anthony Maire, Elorri Arevalo, Hilaire Drouineau, W. Russell Poole, Caroline M. F. Durif, Stéphane Tétard, Ola Håvard Diserud, Ecosystèmes aquatiques et changements globaux (UR EABX), Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Laboratoire National d’Hydraulique et Environnement (EDF R&D LNHE), EDF R&D (EDF R&D), EDF (EDF)-EDF (EDF), Austevoll Research Station (IMR), Institute of Marine Research [Bergen] (IMR), University of Bergen (UiB)-University of Bergen (UiB), NORWEGIAN INSTITUTE FOR NATURE RESEARCH TRONDHEIM NOR, Partenaires IRSTEA, Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA), and MARINE INSTITUTE FURNACE NEWPORT CO MAYO IRELAND GBR
Subjects: 0106 biological sciences, River water temperature, endocrine system, animal structures, Behavioural ecology, Science, [SDV]Life Sciences [q-bio], Climate Change, VDP::Zoologiske og botaniske fag: 480, Climate change, Animal migration, 010603 evolutionary biology, 01 natural sciences, Article, Critically endangered, Downstream (manufacturing), Rivers, Sargasso sea, Animals, 14. Life underwater, Multidisciplinary, Norway, Conservation biology, 010604 marine biology & hydrobiology, Endangered Species, Climate-change ecology, Temperature, Anguilla, Fishery, Habitat, Period (geology), Environmental science, VDP::Zoology and botany: 480, Medicine, Freshwater ecology, Ireland
Abstract: Climate change is modifying the hydrological and thermal regimes of rivers worldwide, threatening the triggering of organisms’ key life-cycle processes. European eel (Anguilla anguilla) is a critically endangered fish species that migrates over several thousand kilometres between its rearing habitats in continental waters of Europe and North Africa and its spawning area in the Sargasso Sea. Downstream migration of adult eels occurs during periods of decreasing river water temperature associated with high discharge but changes in these environmental cues may affected eel migratory conditions. An innovative multivariate method was developed to analyse long-term datasets of daily water temperature, discharge and eel passage in two European rivers. Over the past 50 years, water temperature and discharge increased in both rivers during the downstream migration period from August to November. Silver eels preferentially migrated at temperatures between 10 and 20 °C combined with high discharge. Environmental changes have resulted in the migration of silver eels under warmer water temperatures. This example illustrates how the changes in environmental cues have led to a growing mismatch between the migratory conditions preferentially selected and those actually used, which may threaten the completion of the eel’s life cycle and ultimately the persistence of this already critically endangered species.
Published: 2021

30. Otolith shape analysis and daily increment validation during ontogeny of larval and juvenile European chub Squalius cephalus

Author: Vincent Gennotte, Anthony Maire, Bernadette Bounket, Pierre Gibert, Fabien Morat, Georges Carrel, Maxime Logez, Christine Argillier, Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA), Risques, Ecosystèmes, Vulnérabilité, Environnement, Résilience (RECOVER), Aix Marseille Université (AMU)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA), PSL Research University (PSL), Centre de recherches insulaires et observatoire de l'environnement (CRIOBE), Université de Perpignan Via Domitia (UPVD)-École pratique des hautes études (EPHE)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Excellence CORAIL (LabEX CORAIL), Université des Antilles (UA)-Institut d'écologie et environnement-Université de la Nouvelle Calédonie (UNC)-Université de la Polynésie Française (UPF)-Université de La Réunion (UR)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-École pratique des hautes études (EPHE)-École des hautes études en sciences sociales (EHESS)-Université des Antilles et de la Guyane (UAG)-Institut de Recherche pour le Développement (IRD), Laboratoire National d’Hydraulique et Environnement (EDF R&D LNHE), EDF R&D (EDF R&D), EDF (EDF)-EDF (EDF), Institut méditerranéen de biodiversité et d'écologie marine et continentale (IMBE), Avignon Université (AU)-Aix Marseille Université (AMU)-Institut de recherche pour le développement [IRD] : UMR237-Centre National de la Recherche Scientifique (CNRS), Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Aix Marseille Université (AMU), Université Paris sciences et lettres (PSL), Université de Perpignan Via Domitia (UPVD)-École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS), Université des Antilles (UA)-Institut d'écologie et environnement-Université de la Nouvelle-Calédonie (UNC)-Université de la Polynésie Française (UPF)-Université de La Réunion (UR)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École des hautes études en sciences sociales (EHESS)-Université des Antilles et de la Guyane (UAG)-Institut de Recherche pour le Développement (IRD), Université de Perpignan Via Domitia (UPVD)-École Pratique des Hautes Études (EPHE), Institut de Recherche pour le Développement (IRD)-Université des Antilles et de la Guyane (UAG)-École des hautes études en sciences sociales (EHESS)-École Pratique des Hautes Études (EPHE), and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Université de La Réunion (UR)-Université de la Polynésie Française (UPF)-Université de la Nouvelle-Calédonie (UNC)-Institut d'écologie et environnement-Université des Antilles (UA)
Subjects: Male, 0106 biological sciences, animal structures, European chub, Ontogeny, Cyprinidae, Zoology, Aquatic Science, Sagitta, Otolith, 010603 evolutionary biology, 01 natural sciences, Otolithic Membrane, Age, medicine, Animals, Cluster Analysis, Juvenile, 14. Life underwater, Ecology, Evolution, Behavior and Systematics, Analysis of Variance, Principal Component Analysis, Fourier Analysis, biology, Squalius, Hatching, [SDV.BA]Life Sciences [q-bio]/Animal biology, 010604 marine biology & hydrobiology, Age Factors, technology, industry, and agriculture, Discriminant Analysis, Shape, Increment, biology.organism_classification, Lapilli, Fourier, medicine.anatomical_structure, Larva, Linear Models, Female, sense organs
Abstract: [Departement_IRSTEA]Eaux [TR1_IRSTEA]QUASARE [ADD1_IRSTEA]Dynamique et fonctionnement des écosystèmes; International audience; This assesses features of otoliths from laboratory-reared embryos, larvae and juvenile European chub Squalius cephalus from hatching to 180 days post-hatching (dph). We observed the development of the three pairs of otoliths (lapilli, sagittae and asterisci) and more precisely shape changes, as well as timing and deposition rate of increments of the lapilli. The lapilli and the sagittae were present at hatching, whereas the asterisci formed between 20 and 30 dph. The lapillus and sagitta shapes were round until 20 dph. From 60 dph the anterior and the posterior rostra of the sagittae were well developed, but very thin, making this otolith too fragile to manipulate for further studies of shape and validation of otolith increment deposition rate. The lapilli provided reliable age estimates for free embryos, larvae and juveniles up to 120 dph. However, caution should be taken when ageing fish older than 150 dph as an underestimation was noticeable. The regression of the number of otolith increments on age showed a slope and an intercept not significantly different from 1 and 0, respectively , which indicated that otolith growth increments were deposited on a daily basis, with the first microincrement occurring at hatching. Increment counts were consistent between three interpreters, indicating a consistent and reliable age estimate. This study validates that the otolith increment deposition rate can be used to assess hatching dates and daily growth of wild S. cephalus under 150 dph and in environments similar to the conditions used in this study.
Published: 2019

31. A simple SPH model of a free surface water wave pump: waves above a submerged plate

Author: Damien Violeau, Remi Carmigniani, Agnès Leroy, Laboratoire National d’Hydraulique et Environnement (EDF R&D LNHE), EDF R&D (EDF R&D), and EDF (EDF)-EDF (EDF)
Subjects: Work (thermodynamics), Materials science, 010504 meteorology & atmospheric sciences, 010505 oceanography, Ocean Engineering, Mechanics, 01 natural sciences, Physics::Fluid Dynamics, Simple (abstract algebra), Modeling and Simulation, Free surface, [PHYS.MECA.MEFL]Physics [physics]/Mechanics [physics]/Fluid mechanics [physics.class-ph], ComputingMilieux_MISCELLANEOUS, Physics::Atmospheric and Oceanic Physics, 0105 earth and related environmental sciences, Civil and Structural Engineering
Abstract: In this work, the SPH method is used in 2D to evaluate the pump characteristics of free surface water waves above a submerged plate. The configuration considered here consists of an infinite wave t...
Published: 2019

32. A comprehensive code-to-code comparison study with the modified IEA15MW-UMaine Floating Wind Turbine for H2020 HIPERWIND project

Author: Taeseong Kim, Anand Natarajan, Anaïs Lovera, Emricka Julan, Christophe Peyrard, Matteo Capaldo, Guillaume Huwart, Pauline Bozonnet, Martin Guiton, DTU Wind Energy, EDF Lab Saclay, Laboratoire National d’Hydraulique et Environnement (EDF R&D LNHE), EDF R&D (EDF R&D), EDF (EDF)-EDF (EDF), IFP Energies nouvelles (IFPEN), and European Project: 101006689,HIPERWIND
Subjects: History, benchmark, [SDE.MCG]Environmental Sciences/Global Changes, aero-servo-hydro-elastic model, [SDE]Environmental Sciences, [SPI.NRJ]Engineering Sciences [physics]/Electric power, IEA 15MW, [MATH]Mathematics [math], FOWT, semisubmersible, Computer Science Applications, Education
Abstract: An extensive code-to-code comparison among DIEGO, DLW and HAWC2 has been performed on a floating wind turbine (modified version of UMaine floater with IEAWIND 15MW wind turbine). In total, 10 cases are compared, and a few key results of this comparison are reported in this paper. From the comparisons, it is clearly seen that the results predicted by the three codes are generally agreed well despite some differences in specific degrees of freedom like roll, sway and yaw for the extreme load case, which requires additional investigations.
Published: 2022

33. Single-phase SPH modelling of plunge pool dynamic pressures at a near-prototype scale

Author: Damien Violeau, Pedro Manso, Francisco Taveira-Pinto, Andreia Moreira, Laboratoire National d’Hydraulique et Environnement (EDF R&D LNHE), EDF R&D (EDF R&D), and EDF (EDF)-EDF (EDF)
Subjects: smoothed particle hydrodynamics, Scale (ratio), Astrophysics::High Energy Astrophysical Phenomena, 0208 environmental biotechnology, 02 engineering and technology, 01 natural sciences, Physics::Geophysics, 010305 fluids & plasmas, Physics::Fluid Dynamics, Smoothed-particle hydrodynamics, 0103 physical sciences, Mathematics::Metric Geometry, [PHYS.MECA.MEFL]Physics [physics]/Mechanics [physics]/Fluid mechanics [physics.class-ph], Single phase, Plunge pool, Hydropower, ComputingMilieux_MISCELLANEOUS, Water Science and Technology, Civil and Structural Engineering, plunging jets, Jet (fluid), dynamic pressures, business.industry, Turbulence, sph, Mechanics, 020801 environmental engineering, Physics::Space Physics, Compressibility, business, Geology, spillways
Abstract: The turbulent plunging jet of a nearly incompressible fluid into a stagnant fluid is of great importance in many practical applications, especially for the engineering of hydropower. As an example, the dynamic load exerted by the impact of turbulent high-velocity jets into a pool must be estimated to evaluate the potential destabilization of a rock bed or dam's structure. Modelling plunging jets in the laboratory presents a challenge due to the complex two-phase environment, which requires models to be built at near-prototype scales. This paper deals with the application of a three-dimensional weakly compressible smoothed particle hydrodynamics (SPH) model to study a circular jet impinging into a water flat pool, at a near-prototype scale. To identify the level of reliability of the computed parameters, validation of the pool bottom pressures is carried out by comparison with existing experimental data. The self-similarity of the jet's centreline velocity is correctly reproduced and the computed maximum dynamic pressures near the stagnation point are reasonably accurate. The differences observed are mainly attributed to the non-consideration of the air phase.
Published: 2021

34. Modélisation non-linéaire de champs multidimensionnels guidée par la donnée : application aux écoulements côtiers hydromorphodynamiques

Author: Mouradi, Rem-Sophia, Climat, Environnement, Couplages et Incertitudes [Toulouse] (CECI), CERFACS-Centre National de la Recherche Scientifique (CNRS), Laboratoire National d’Hydraulique et Environnement (EDF R&D LNHE), EDF R&D (EDF R&D), EDF (EDF)-EDF (EDF), Institut national polytechnique de Toulouse (INPT), Olivier Thual, Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE), and MOURADI, Rem-Sophia
Subjects: uncertainty quantification, Physically-based data-driven modelling, transport sédimentaire, geosciences, physically-based data-driven modelling, hydrodynamique, [STAT.OT]Statistics [stat]/Other Statistics [stat.ML], assimilation de données, sediment transport, sensitivity analysis, [PHYS.MECA.MEFL] Physics [physics]/Mechanics [physics]/Fluid mechanics [physics.class-ph], [PHYS.MECA.MEFL]Physics [physics]/Mechanics [physics]/Fluid mechanics [physics.class-ph], data assimilation, Uncertainty quantification, quantification d'incertitudes, modélisation physique guidée par la donnée, apprentissage statistique, Sediment transport, coastal intake, [STAT.OT] Statistics [stat]/Other Statistics [stat.ML], Statistical learning, [STAT] Statistics [stat], [STAT]Statistics [stat], statistical learning, chenaux côtiers, Data assimilation, hydrodynamics, Hydrodynamics, data-based prediction, Data-based prediction, Sensitivity analysis, prédiction à base de données, Geosciences, analyse de sensibilité
Abstract: This thesis contributions belong to the general framework of data-based and physically-based data-driven modelling. An efficient approach for Machine Learning (ML), as well as a speed-up technique for Data Assimilation (DA), have been developed. For this purpose, Dimensionality Reduction (DR) and stochastic spectral modelling were used. In particular, a coupling between Proper Orthogonal Decomposition (POD) and Polynomial Chaos Expansion (PCE) is at the center of this thesis contributions. POD and PCE have widely proved their worth in their respective frameworks, and the idea was to combine them for optimal field measurement based forecasting, and ensemble-based acceleration technique for variational DA. For this purpose, (i) a physically interpretable POD-PCE ML for non-linear multidimensional fields was developed in the Neural Networks (NN) paradigm and (ii) a hybrid ensemble-variational DA approach for parametric calibration was proposed with adapted calculations of POD-PCE metamodelling error covariance matrix. The proposed techniques were assessed in the context of an industrial application, for the study of sedimentation in a coastal power plant's water intake. Water intakes ensure plant cooling via a pumping system. They can be subject to sediment accumulation, which represents a clogging risk and requires costly dredging operations. For monitoring and safety reasons, the power plant stakeholders asked for a predictive tool that could be run in operational conditions. Data collected during many years of monitoring in the study area were provided. The objective was then to achieve comprehensive analysis of the flow and sediment dynamics, as well as to develop an optimal model in terms of forecasting accuracy, physical meaning, and required computational time. Uncertainty reduction and computational efficiency were therefore starting points for all proposed contributions. In addition to the previously proposed methods, Uncertainty Quantificiation (UQ) studies were undertaken. Specifically, (i) uncertainties related to tidal hydrodynamic modelling, resulting from common modelling choices (domain size, empirical closures) were investigated. POD patterns resulting from measurements and numerical scenarios were compared; (ii) UQ study of the sediment transport modelling in the intake, in a highdimensional framework, was achieved. Investigations were based on appropriate DR. Infact, POD patterns of Boundary Conditions (BC) and Initial Conditions (IC), resulting from hydrodynamic simulations outputs and from bathymetry measurements respectively, were used. A perspective of this work would be to implement a hybrid POD-PCE model, using both measured and numerically emulated data, to better understand and predict complex physical processes. This approach would offer a complete, fast and efficient tool for operational predictions., Les contributions de cette thèse figurent dans le cadre général de la modélisation à base de données et des approches physiques guidées par des données. Une méthode d'apprentissage statistique, ainsi qu'une technique d'accélération pour l'Assimilation de Données (AD), ont été développées. Pour cela, la Réduction de Dimension et la modélisation stochastique spectrale sont utilisées. En particulier, un couplage entre Décomposition en modes Propres Orthogonaux (POD) et Expansion par Polynômes du Chaos (PCE), est au centre des différentes contributions. Les techniques POD et PCE sont toutes deux largement reconnues. L'idée ici estde les combiner pour mettre en place une prédiction optimale à base de données de mesures, et accélérer les techniques d'Assimilation de Données variationnelle sur la base d'une approche d'ensemble. Pour cela, (i) un modèle de Machine Learning POD-PCE, interprétable physiquement, et adapté aux champs multidimensionnels non-linéaires, a été développé dans un paradigme de Réseaux de Neurones et (ii) une approche ensembliste variationnelle hybride d'AD, pour la calibration paramétrique a été proposée, avec un calcul adapté de la matrice de covariance d'erreur du métamodèle POD-PCE. Les approches proposées ont été motivées par une problématique industrielle, avec une question physique complexe : la sédimentation dans un chenal d'amenée bord-de-merd'une centrale électrique. Les chenaux d'amenée assurent le refroidissement des centrales à travers un système de pompage. Ils peuvent être sujets à une accumulation de sédiments, ce qui représente un risque de colmatage et requiert des opérations de dragage coûteuses. Pour des raisons de gestion et de sécurité, l'industriel opérant la centrale d'intérêt demande un outil prédictif pour des conditions opérationnelles. Les données collectées durant plusieurs années de gestion ont été fournies. L'objectif est d'analyser la dynamique observée, ainsi que de développer un modèle optimal, à la fois prédictif, physiquement interprétable, et à coût de calcul limité. La réduction de l'incertitude et la diminution du temps de simulation ont donc été un point de départ pour toutes les contributions proposées. En supplément des méthodes citées précédemment, des études de Quantification d'Incertitudes (UQ) ont été menées. Plus précisément, (i) les incertitudes liées à la modélisation hydrodynamique de la marée, résultant de choix de modélisation communs (taille de domaine, lois empiriques), ont été investiguées. Les motifs POD des mesures et des scénarios numériques ont été comparés ; (ii) l'étude UQ de la modélisation du transport sédimentaire dans le chenal, dans un cadre à haute-dimension, a été réalisée. Les investigations se sont basées sur une Réduction de Dimension appropriée. En effet, les motifs POD des Conditions aux Limites, et ceux des Conditions Initiales, résultant de simulations hydrodynamiques et de mesures bathymétriques respectivement, ont été utilisées. Une perspective de ce travail serait d'implémenter un modèle POD-PCE hybride, utilisant à la fois des données de mesures et des données simulées numériquement, pourmieux comprendre et prédire des processus physiques complexes. Cette approche offrirait un outil complet, rapide et efficace pour des prédictions opérationnelles.
Published: 2021

35. Physically interpretable machine learning algorithm on multidimensional non-linear fields

Author: Cédric Goeury, Pablo Tassi, Fabrice Zaoui, Rem-Sophia Mouradi, Olivier Thual, EDF R&D (EDF R&D), EDF (EDF), Laboratoire National d’Hydraulique et Environnement (EDF R&D LNHE), EDF (EDF)-EDF (EDF), Climat, Environnement, Couplages et Incertitudes [Toulouse] (CECI), CERFACS-Centre National de la Recherche Scientifique (CNRS), Institut de mécanique des fluides de Toulouse (IMFT), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées, Laboratoire d'Hydraulique Saint-Venant / Saint-Venant laboratory for Hydraulics (Saint-Venant), École des Ponts ParisTech (ENPC)-Centre d'Etudes et d'Expertise sur les Risques, l'Environnement, la Mobilité et l'Aménagement (Cerema)-EDF R&D (EDF R&D), CECI, CERFACS / CNRS (CECI), Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique - CNRS (FRANCE), EDF (FRANCE), Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), Centre d'études et d'expertise sur les risques, l'environnement, la mobilité et l'aménagement - CEREMA (FRANCE), Centre Européen de Recherche et Formation Avancées en Calcul Scientifique - CERFACS (FRANCE), Ecole des Ponts ParisTech (FRANCE), and MOURADI, Rem-Sophia
Subjects: [SDE] Environmental Sciences, FOS: Computer and information sciences, Computer Science - Machine Learning, Physics and Astronomy (miscellaneous), Computer science, Mécanique des fluides, 010103 numerical & computational mathematics, computer.software_genre, 01 natural sciences, Field (computer science), Machine Learning (cs.LG), [SPI.MECA.MEFL]Engineering Sciences [physics]/Mechanics [physics.med-ph]/Fluids mechanics [physics.class-ph], [SPI]Engineering Sciences [physics], [STAT.ML]Statistics [stat]/Machine Learning [stat.ML], Statistics - Machine Learning, Numerical Analysis, [STAT.ME] Statistics [stat]/Methodology [stat.ME], Polynomial chaos, Applied Mathematics, Machine Learning (ML), Computational Physics (physics.comp-ph), Computer Science Applications, 010101 applied mathematics, Computational Mathematics, Modeling and Simulation, [SDE]Environmental Sciences, Pattern recognition (psychology), Physics - Computational Physics, [STAT.ME]Statistics [stat]/Methodology [stat.ME], Data compression, [SPI] Engineering Sciences [physics], FOS: Physical sciences, Context (language use), Machine Learning (stat.ML), Machine learning, Methodology (stat.ME), Geoscieces, Data-Driven Model (DDM), 0101 mathematics, Uncertainty quantification, Statistics - Methodology, Polynomial Chaos Expansion (PCE), business.industry, Dimensionality reduction, [STAT.ML] Statistics [stat]/Machine Learning [stat.ML], Proper Orthogonal Decomposition (POD), Physics - Data Analysis, Statistics and Probability, Data quality, Dimensionality Reduction (DM), Artificial intelligence, business, computer, Data Analysis, Statistics and Probability (physics.data-an)
Abstract: International audience; In an ever-increasing interest for Machine Learning (ML) and a favorable data development context, we here propose an original methodology for data-based prediction of two-dimensional physical fields. Polynomial Chaos Expansion (PCE), widely used in the Uncertainty Quantification community (UQ), has long been employed as a robust representation for probabilistic input-to-output mapping. It has been recently tested in a pure ML context, and shown to be as powerful as classical ML techniques for point-wise prediction. Some advantages are inherent to the method, such as its explicitness and adaptability to small training sets, in addition to the associated probabilistic framework. Simultaneously, Dimensionality Reduction (DR) techniques are increasingly used for pattern recognition and data compression and have gained interest due to improved data quality. In this study, the interest of Proper Orthogonal Decomposition (POD) for the construction of a statistical predictive model is demonstrated. Both POD and PCE have amply proved their worth in their respective frameworks. The goal of the present paper was to combine them for a field-measurement-based forecasting. The described steps are also useful to analyze the data. Some challenging issues encountered when using multidimensional field measurements are addressed, for example when dealing with few data. The POD-PCE coupling methodology is presented, with particular focus on input data characteristics and training-set choice. A simple methodology for evaluating the importance of each physical parameter is proposed for the PCE model and extended to the POD-PCE coupling.
Published: 2021

36. Temporary turbine and reservoir level management to improve downstream migration of juvenile salmon through a hydropower complex

Author: Dominique Courret, Romain Roy, Stéphane Tétard, Nils Teichert, Jocelyn Rancon, Centre National de la Recherche Scientifique - CNRS (FRANCE), EDF (FRANCE), Ecole Nationale Supérieure de Mécanique et d'Aérotechnique - ENSMA (FRANCE), Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE), Sorbonne Université (FRANCE), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), Université de Caen Basse-Normandie (FRANCE), Université de Poitiers (FRANCE), Office français de la biodiversité - OFB (FRANCE), Conservatoire National du Saumon Sauvage - CNSS (FRANCE), Ingénierie Conseil Expertise - ICEO (FRANCE), Museum National d'Histoire Naturelle - MNHN (FRANCE), Université des Antilles et de la Guyane (FRANCE), Laboratoire National d'Hydraulique et d'Environnement - LNHE (Chatou, France), Institut de Mécanique des Fluides de Toulouse - IMFT (Toulouse, France), ISAE-ENSMA Ecole Nationale Supérieure de Mécanique et d'Aérotechnique (FRANCE), ICEO - Ingénierie et du Criblage d’Enzymes Originales (TBI-ICEO), Toulouse Biotechnology Institute (TBI), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Laboratoire National d’Hydraulique et Environnement (EDF R&D LNHE), EDF R&D (EDF R&D), EDF (EDF)-EDF (EDF), Biologie des Organismes et Ecosystèmes Aquatiques (BOREA), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-Muséum national d'Histoire naturelle (MNHN)-Institut de Recherche pour le Développement (IRD)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université des Antilles (UA), Conservatoire National du Saumon Sauvage (CNSS), Institut de mécanique des fluides de Toulouse (IMFT), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées, Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Université de Toulouse (UT)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), and Université de Toulouse (UT)
Subjects: 0106 biological sciences, Atlantic salmon, Shutdown, Biodiversité et Ecologie, Mécanique des fluides, operational management, Turbine shutdown, Ingénierie de l'environnement, Management, Monitoring, Policy and Law, Aquatic Science, Residence time (fluid dynamics), 010603 evolutionary biology, 01 natural sciences, Turbine, lcsh:Aquaculture. Fisheries. Angling, [SPI.MECA.MEFL]Engineering Sciences [physics]/Mechanics [physics.med-ph]/Fluids mechanics [physics.class-ph], migratory delay, [SDV.EE.ECO]Life Sciences [q-bio]/Ecology, environment/Ecosystems, Downstream (manufacturing), Telemetry, Juvenile, 14. Life underwater, Hydropower, Nature and Landscape Conservation, Water Science and Technology, Operational management, lcsh:SH1-691, Ecology, turbine shutdown, [SDE.IE]Environmental Sciences/Environmental Engineering, business.industry, downstream migration, 010604 marine biology & hydrobiology, 6. Clean water, Migratory delay, Fishery, Ecosystèmes, atlantic salmon, Environmental science, Downstream migration, [SDE.BE]Environmental Sciences/Biodiversity and Ecology, business
Abstract: International audience; Developing management rules to improve downstream migration of salmon smolts in large hydropower plants is essential to limit mortality and migration delay. A 2-year telemetry study was conducted to assess the efficiency of temporary measures to enhance the safety and speed of juvenile salmon passage through the Poutès dam (Allier River, France). 124 smolts were tracked through the reservoir and downstream of the dam, during implementation of turbine modulation and/or shutdown during night and reservoir level lowering. Level lowering significantly reduced median residence time from 3.4 days to 4.4 hours. However, even with high spill during turbine modulation, the risk of smolt being drawn toward the turbines was increased at low reservoir level due to the site’s configuration, greater proximity to the surface and weak repulsive effect of the rack. Moreover, results revealed that a substantial proportion of smolts can migrate during daytime and twilight during floods, even at the beginning of the migration period. Thus targeted turbine shutdown has a good potential to protect smolts, but implementation requires studies taking account of site specificities and a flexible approach.
Published: 2021

37. Strategies for hydrologic ensemble generation and calibration: On the merits of using model-based predictors

Author: Anne-Laure Tiberi-Wadier, Philippe Sergent, Maxime Taillardat, Céline Monteil, Sophie Ricci, François Bouttier, Nicole Goutal, Centre d'Etudes et d'Expertise sur les Risques, l'Environnement, la Mobilité et l'Aménagement (Cerema), EDF R&D (EDF R&D), EDF (EDF), Centre Européen de Recherche et de Formation Avancée en Calcul Scientifique (CERFACS), Météo-France Direction Interrégionale Sud-Est (DIRSE), Météo-France, Centre national de recherches météorologiques (CNRM), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Laboratoire National d’Hydraulique et Environnement (EDF R&D LNHE), EDF (EDF)-EDF (EDF), Météo France-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), CERFACS, and Météo France
Subjects: Quantile Regression Forest, 010504 meteorology & atmospheric sciences, Calibration (statistics), 0207 environmental engineering, Ensemble Prediction System, 02 engineering and technology, [SDU.STU.ME]Sciences of the Universe [physics]/Earth Sciences/Meteorology, 01 natural sciences, Standard deviation, Copula (probability theory), Global Sensitivity Analysis, Statistics, Hydrometeorology, 2010 MSC: 00-01, 99-00, [SDU.STU.HY]Sciences of the Universe [physics]/Earth Sciences/Hydrology, 020701 environmental engineering, 0105 earth and related environmental sciences, Water Science and Technology, Mathematics, MORDOR-TS, Odet catchment, Quantile regression, 13. Climate action, Trajectory, Hydrologic Ensemble Forecast, Smoothing, Quantile
Abstract: International audience; This paper investigates the hydrometeorological chain with an ensemble approach. The objective is the generation of Hydrologic Ensemble Forecasts (HEF) on the Odet catchment (France, Brittany), using the Quantile Regression Forest (QRF) method usually applied for the ensemble calibration of meteorological forecats. First, a Global Sensitivity Analysis (GSA) in the distributed MORDOR-TS model is carried out taking into account uncertainty in forecasted rain with AromeEPS-RR1 and in model parameters. GSA highlights the role and importance of the different hydrologic model parameters during rain events and allows to only take into account the most influent parameters for the generation of an Hydrologic Ensemble Forecast (HEF). Three strategies for the generation of HEF are then compared. First (i), a raw ensemble is built with a model-based only approach using the deterministic forecast rainfall Expert-RR3 and perturbed model parameters, without further statistical calibration. Then, the QRF calibration method is used to generate two ensembles of quantiles: (ii) the observation-based approach uses only predictors that are independent from hydrology, whereas (iii) the combined model and observation approach combines these predictors with statistics of the raw hydrologic ensemble (mean, standard deviation). This latter approach was shown to outperfom the previous ones, enhancing the importance of the choice of the predictors in the QRF method. In the prospect of using the hydrologic ensemble as input for hydraulic simulation, the Ensemble Copula Coupling method (ECC) and a trajectory smoothing procedure is then applied on (iii). This step slightly deteriorates the reliability of hourly streamflows, yet Continuous Ranked Probability Score (CRPS) and forecast skills on the cumulated or maximum streamflows are improved.
Published: 2021

38. Rebound in functional distinctiveness following warming and reduced fishing in the North Sea

Author: Nicolas Loiseau, Juliette Murgier, Anthony Maire, David Mouillot, Arnaud Auber, Cyrille Violle, François Munoz, Matthew McLean, Université Bourgogne Franche-Comté [COMUE] (UBFC), Dalhousie University [Halifax], Laboratoire National d’Hydraulique et Environnement (EDF R&D LNHE), EDF R&D (EDF R&D), EDF (EDF)-EDF (EDF), MARine Biodiversity Exploitation and Conservation (UMR MARBEC), Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Institut de Recherche pour le Développement (IRD), Toxicologie Intégrative & Métabolisme (ToxAlim-TIM), ToxAlim (ToxAlim), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Ecole Nationale Vétérinaire de Toulouse (ENVT), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Ecole d'Ingénieurs de Purpan (INPT - EI Purpan), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Laboratoire Interdisciplinaire de Physique [Saint Martin d’Hères] (LIPhy ), Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA), Centre d’Ecologie Fonctionnelle et Evolutive (CEFE), Université Paul-Valéry - Montpellier 3 (UPVM)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud])-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Laboratoire Ressources halieutiques Manche Mer du nord, IFREMER Centre Manche Mer du Nord, (HMMN), Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER), Institut de Recherche pour le Développement (IRD)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Université de Toulouse (UT)-Université de Toulouse (UT)-Ecole Nationale Vétérinaire de Toulouse (ENVT), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Ecole d'Ingénieurs de Purpan (INPT - EI Purpan), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Université Paul-Valéry - Montpellier 3 (UPVM)-École Pratique des Hautes Études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud])-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut Agro - Montpellier SupAgro, Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro), Laboratoire Ressources halieutiques Boulogne sur mer (LRHBL), Halieutique Manche Mer du Nord (HMMN), and Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)
Subjects: 0106 biological sciences, Climate Change, [SDE.MCG]Environmental Sciences/Global Changes, Fishing, vulnerability, Fishing in the North Sea, Biology, 010603 evolutionary biology, 01 natural sciences, General Biochemistry, Genetics and Molecular Biology, diversity, Common species, Abundance (ecology), IUCN Red List, Animals, Humans, rarity, Ecosystem, 14. Life underwater, global change, General Environmental Science, General Immunology and Microbiology, trait, Ecology, 010604 marine biology & hydrobiology, international trawling effort, conservation, r-selection, General Medicine, functional diversity, fishes, fisheries, ecosystem functioning, Threatened species, climate-change, Ecosystem management, Sharks, community, North Sea, ecology, ecological trait, [SDE.BE]Environmental Sciences/Biodiversity and Ecology, General Agricultural and Biological Sciences, Research Article
Abstract: WOS:000617658000001; International audience; Functionally distinct species (i.e. species with unique trait combinations in the community) can support important ecological roles and contribute disproportionately to ecosystem functioning. Yet, how functionally distinct species have responded to recent climate change and human exploitation has been widely overlooked. Here, using ecological traits and long-term fish data in the North Sea, we identified functionally distinct and functionally common species, and evaluated their spatial and temporal dynamics in relation to environmental variables and fishing pressure. Functionally distinct species were characterized by late sexual maturity, few, large offspring, and high parental care, many being sharks and skates that play critical roles in structuring food webs. Both functionally distinct and functionally common species increased in abundance as ocean temperatures warmed and fishing pressure decreased over the last three decades; however, functionally distinct species increased throughout the North Sea, but primarily in southern North Sea where fishing was historically most intense, indicating a rebound following fleet decommissioning and reduced harvesting. Yet, some of the most functionally distinct species are currently listed as threatened by the IUCN and considered highly vulnerable to fishing pressure. Alarmingly these species have not rebounded. This work highlights the relevance and potential of integrating functional distinctiveness into ecosystem management and conservation prioritization.
Published: 2021

39. Coupling 3D hydraulic simulation and fish telemetry data to characterize the behavior of migrating smolts approaching a bypass

Author: Eric De Oliveira, Remi Carmigniani, Hilaire Drouineau, Hervé Capra, Noor Ben Jebria, Stéphane Tétard, Laboratoire National d’Hydraulique et Environnement (EDF R&D LNHE), EDF R&D (EDF R&D), and EDF (EDF)-EDF (EDF)
Subjects: 0106 biological sciences, [SDV.EE]Life Sciences [q-bio]/Ecology, environment, [SDE.IE]Environmental Sciences/Environmental Engineering, 010604 marine biology & hydrobiology, Fish species, Fragmentation (computing), 010603 evolutionary biology, 01 natural sciences, 6. Clean water, Fishery, Coupling (computer programming), Telemetry, Hydraulic simulation, Environmental science, %22">Fish , 14. Life underwater, ComputingMilieux_MISCELLANEOUS
Abstract: Human-induced river fragmentation is a major threat to migratory fish species. Restoring river connectivity requires the construction of fish passage solutions, such as fishways for upstream and do...
Published: 2021

40. Consistent but secondary influence of hydropeaking on stream fish assemblages in space and time

Author: Nicolas Lamouroux, Hervé Capra, A. Barillier, Anthony Maire, Clarisse Judes, V. Gouraud, Riverly (Riverly), Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), EDF R&D LNHE - Laboratoire National d’Hydraulique et Environnement, Chatou Cedex, France, HYNES team (INRAE-EDF E&D), Chatou, France, and EDF CIH, Savoie Technolac, La Motte Servolex, France
Subjects: 0106 biological sciences, Hydrology, [SDV.EE]Life Sciences [q-bio]/Ecology, environment, 010504 meteorology & atmospheric sciences, business.industry, 010604 marine biology & hydrobiology, high flow variations, fish community structure, Electricity demand, 01 natural sciences, flow management, Habitat, Flow velocity, 13. Climate action, Flow management, Environmental science, %22">Fish , 14. Life underwater, business, Hydropower, 0105 earth and related environmental sciences, hydraulic habitat
Abstract: International audience; Hydropeaking corresponds to rapid artificial discharge variations, designed to address sub-daily peaks in electricity demand. It generates rapid changes in physical habitat (e.g., flow velocity and water depth) with potential impacts on stream assemblages. For assessing the generality of hydropeaking effects on fish assemblages, we present an original combination of spatial (among 45 reaches, including six groups of nearby reaches) and temporal (over 3-17 years) analyses of these effects. Our analyses involved descriptions of natural and artificial hydraulic variations in reaches, obtained after translating hourly discharge data into hydraulics. We found that the influence of hydropeaking was secondary compared to well-known spatial variations in fish assemblage structure along longitudinal gradients, and negative influences of floods on annual densities. However, the spatial and temporal analyses consistently suggested that hydropeaking may disfavour fish species typical of medium-sized streams relative to species of headwater streams (Salmo trutta, Phoxinus phoxinus, Cottus gobio). The magnitude of hydropeaking effects observed here, as well as an apparent weaker effect of ramping rates than the frequency of hydropeaks, may be due to lower ramping rates in our data set than in other studies.
Published: 2021

41. Cosmogenic tsunamic risk assessment: a first application to the European Atlantic coasts

Author: Damien Violeau, Laboratoire National d’Hydraulique et Environnement (EDF R&D LNHE), EDF R&D (EDF R&D), and EDF (EDF)-EDF (EDF)
Subjects: Return period, 021110 strategic, defence & security studies, Atmospheric Science, geography, Hydrogeology, geography.geographical_feature_category, 010504 meteorology & atmospheric sciences, Continental shelf, 0211 other engineering and technologies, Probabilistic logic, 02 engineering and technology, Shoaling and schooling, Geodesy, 01 natural sciences, Upper and lower bounds, Numerical integration, 13. Climate action, Natural hazard, Earth and Planetary Sciences (miscellaneous), [PHYS.MECA.MEFL]Physics [physics]/Mechanics [physics]/Fluid mechanics [physics.class-ph], Geology, ComputingMilieux_MISCELLANEOUS, 0105 earth and related environmental sciences, Water Science and Technology
Abstract: We address the question of cosmogenic tsunamis, i.e., tsunamis due to the fall of an asteroid in the ocean, in particular on the Atlantic coasts of Europe. We apply Ward and Asphaug's method (Deep-Sea Res II 49:1073–1079, 2002) for assessing this probabilistic return period of tsunami waves, with simplifying assumptions allowing writing their results in the form of analytic formulae, some of them involving simple integrals to be computed by numerical quadrature. We also account for uncertainties, (still following Ward and Asphaug (Deep-Sea Res II 49:1073–1079, 2002) on a simplified line. An upper bound of continental shelf shoaling is estimated ad hoc. The influence of several parameters is also analyzed, in particular the effect of tide is briefly addressed.
Published: 2021

42. Effect of water warming on the structure of biofilm-dwelling communities

Author: Anthony Maire, Nabil Majdi, Jana Uthoff, Walter Traunspurger, Pascal Laffaille, Universität Bielefeld = Bielefeld University, Laboratoire Ecologie Fonctionnelle et Environnement (LEFE), Institut Ecologie et Environnement (INEE), Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT), Laboratoire National d’Hydraulique et Environnement (EDF R&D LNHE), EDF R&D (EDF R&D), EDF (EDF)-EDF (EDF), Laboratoire Ecologie Fonctionnelle et Environnement (ECOLAB), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut Ecologie et Environnement (INEE), Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS), and EDF (EDF)
Subjects: 0106 biological sciences, Bacterivore, River ecosystem, Evolution, Population, General Decision Sciences, Context (language use), 010501 environmental sciences, 010603 evolutionary biology, 01 natural sciences, Behavior and Systematics, 14. Life underwater, education, Ecology, Evolution, Behavior and Systematics, 0105 earth and related environmental sciences, Invertebrate, Trophic level, Biomass (ecology), education.field_of_study, Ecology, Aquatic ecosystem, 15. Life on land, 13. Climate action, [SDE]Environmental Sciences, Environmental science
Abstract: Water warming, either resulting from global or local drivers, is of growing concern for aquatic environments. Changes in thermal regimes may alter the functioning and the trophic dynamics of river ecosystems as most aquatic biota like micro-algae, invertebrates, or fish are poikilotherms. Because biofilms integrate basal and intermediate components of aquatic food webs, examination of their responses to warming should contribute to a better understanding of the effects of ongoing climate change on river ecosystems. In this study, we considered sites that were or were not exposed directly to thermal effluents from a nuclear power plant as “in situ laboratories” of the effect of climate change and water warming. To compare the structure of algal and invertebrate communities dwelling in epilithic biofilms subjected to different thermal regimes in the Garonne River, sets of concrete tiles were placed in the river and the biofilm growing on these standard substrates was sampled after two months of colonisation. The site located within the thermal plume directly downstream of the thermal effluents showed warmer average water temperature (mean ΔT of about 1.5 °C over the study period) and greater daily temperature fluctuations in comparison to the control site. Algal and invertebrate biomass did not differ significantly, but the structure of communities differed markedly between sites. At the heated site, the proportion of cyanobacteria was higher, while there were fewer micro-crustaceans and larvae of insects and bivalves. However, the population of chironomids showed a greater proportion of relatively large individuals. Interestingly, nematodes were more abundant, and their communities comprised more species at the heated site. Their feeding-types were also more diverse showing a greater proportion of algivores, large-sized omnivorous and predatory species. Changes in the abundance and age structure further showed that some bacterivore species, such as Eumonhystera vulgaris, thrived especially well at the heated site, whereas another bacterivore, Monhystrella paramacrura, thrived well at the control site. In the context of climate change, our results highlight that warmer and more fluctuating water temperatures have the potential to alter the body-size spectrum, species composition, distribution of feeding specialisations and age structure within biofilm-dwelling communities.
Published: 2020

43. The Navier-Stokes system with temperature and salinity for free surface flows Part II: Numerical scheme and validation

Author: Boittin, Léa, Bouchut, François, Bristeau, Marie-Odile, Mangeney, Anne, Sainte Marie, Jacques, Souillé, Fabien, Numerical Analysis, Geophysics and Ecology (ANGE), Inria de Paris, Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria)-Laboratoire Jacques-Louis Lions (LJLL (UMR_7598)), Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP), Université Gustave Eiffel (UNIV GUSTAVE EIFFEL), Institut de Physique du Globe de Paris (IPGP), Institut national des sciences de l'Univers (INSU - CNRS)-IPG PARIS-Université de La Réunion (UR)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP), Laboratoire National d’Hydraulique et Environnement (EDF R&D LNHE), EDF R&D (EDF R&D), EDF (EDF)-EDF (EDF), The authors acknowledge the Inria Project Lab 'Algae in Silico' for its financial support. This research is also supported by the ERC SLIDEQUAKES ERC-CG-2013-PE10-617472., European Project: 617472,EC:FP7:ERC,ERC-2013-CoG,SLIDEQUAKE(2014), Laboratoire Analyse et Mathématiques Appliquées (LAMA), Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Centre National de la Recherche Scientifique (CNRS)-Université Gustave Eiffel, Centre d'Etudes et d'Expertise sur les Risques, l'Environnement, la Mobilité et l'Aménagement - Direction Centre-Est (Cerema Direction Centre-Est), Centre d'Etudes et d'Expertise sur les Risques, l'Environnement, la Mobilité et l'Aménagement (Cerema), Université Paris Diderot - Paris 7 (UPD7)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), and Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Centre National de la Recherche Scientifique (CNRS)-Université Gustave Eiffel (UNIV GUSTAVE EIFFEL)
Subjects: [SDU.OCEAN]Sciences of the Universe [physics]/Ocean, Atmosphere, [SPI]Engineering Sciences [physics], Layer-averaged formulation, [PHYS.MECA.MEFL]Physics [physics]/Mechanics [physics]/Mechanics of the fluids [physics.class-ph], Free surface flows, Finite volume scheme, Variable density flows, [PHYS.MECA.MEFL]Physics [physics]/Mechanics [physics]/Fluid mechanics [physics.class-ph], Navier-Stokes equations, [INFO.INFO-MO]Computer Science [cs]/Modeling and Simulation, [MATH.MATH-NA]Mathematics [math]/Numerical Analysis [math.NA], [SPI.MECA.MEFL]Engineering Sciences [physics]/Mechanics [physics.med-ph]/Fluids mechanics [physics.class-ph]
Abstract: In this paper, we propose a numerical scheme for the layer-averaged Euler with variable density and the Navier-Stokes-Fourier systems presented in part I (Boittin et al., 2018). These systems model hydrostatic free surface flows with density variations. We show that the finite volume scheme presented is well balanced with regards to the steady state of the lake at rest and preserves the positivity of the water height. A maximum principle on the density is also proved as well as a discrete entropy inequality in the case of the Euler system with variable density. Some numerical validations are finally shown with comparisons to 3D analytical solutions and experiments.
Published: 2020

44. Active Acoustic Signature Extraction by Machine Learning Data Analysis for Underwater Fish Counters

Author: Eric de Oliveira, Franck Hieramente, Alexandre Girard, Gabriel Vasile, Guy d'Urso, Olivier Philippe, GIPSA - Signal Images Physique (GIPSA-SIGMAPHY), GIPSA Pôle Sciences des Données (GIPSA-PSD), Grenoble Images Parole Signal Automatique (GIPSA-lab), Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP ), Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP ), Université Grenoble Alpes (UGA)-Grenoble Images Parole Signal Automatique (GIPSA-lab), Université Grenoble Alpes (UGA), Laboratoire National d’Hydraulique et Environnement (EDF R&D LNHE), EDF R&D (EDF R&D), EDF (EDF)-EDF (EDF), OSEAN S.A.S [Le Pradet], and Osean
Subjects: 0106 biological sciences, business.industry, Computer science, fish classification, Ultrasound, 0211 other engineering and technologies, Pattern recognition, 02 engineering and technology, 010603 evolutionary biology, 01 natural sciences, Ultrasonic imaging, underwater acoustics, machine learning, Acoustic signature, %22">Fish , Extraction (military), 14. Life underwater, Artificial intelligence, Underwater, business, [SPI.SIGNAL]Engineering Sciences [physics]/Signal and Image processing, 021101 geological & geomatics engineering
Abstract: International audience; This paper illustrates our recent advances in terms of supervised classification of different acoustics signatures employed for fish monitoring by the ACOUEAU active ultrasound system. The obtained results are analyzed, both qualitatively and quantitatively, by taking into consideration five target types.
Published: 2020

45. Solid/liquid ratios of trace elements and radionuclides during a Nuclear Power Plant liquid discharge in the Seine River: Field measurements vs geochemical modeling

Author: Beatriz Lourino-Cabana, Alexandre Gélabert, Yann Sivry, Svetlana M Ilina, Laura Marang, Frederic Coppin, Marc F. Benedetti, Frédérique Eyrolle, Patrick Boyer, Institut de Physique du Globe de Paris, Laboratoire National d’Hydraulique et Environnement (EDF R&D LNHE), EDF R&D (EDF R&D), EDF (EDF)-EDF (EDF), Institut de Radioprotection et de Sûreté Nucléaire (IRSN), Laboratoire de Radioécologie et d'Ecotoxicologie (DEI/SECRE/LRE), Université de Paris (1896-1970), Institut de Physique du Globe de Paris (IPGP), and Institut national des sciences de l'Univers (INSU - CNRS)-IPG PARIS-Université de La Réunion (UR)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP)
Subjects: 010504 meteorology & atmospheric sciences, Health, Toxicology and Mutagenesis, Alkalinity, Analytical chemistry, 010501 environmental sciences, partition coefficient, 01 natural sciences, Adsorption, Radiation Monitoring, [SDU.STU.GC]Sciences of the Universe [physics]/Earth Sciences/Geochemistry, Dissolved organic carbon, Environmental Chemistry, Waste Management and Disposal, radionuclides, 0105 earth and related environmental sciences, Geochemical modeling, River, Radionuclide, Trace elements, Trace element, General Medicine, Particulates, Pollution, 6. Clean water, Partition coefficient, 13. Climate action, Nuclear Power Plants, Environmental science, France, Water Pollutants, Chemical, Environmental Monitoring
Abstract: International audience; This study focuses on the determination of field solid/liquid ratios (Rd) values of trace element (TE) and radionuclide (RN) in the Seine River (France) during a concerted low radioactivity level liquid regulatory discharge performed by a Nuclear Power Plant (NPP) and their confrontation with Kd values calculated from geochemical modeling. This research focuses on how field Rd measurements of TE and RN can be representative of Kd values and how Kd models should be improved.For this purpose 5 sampling points of the Seine River during a NPP’s liquid discharge were investigated: upstream from the discharge in order to assess the natural background values in the area of effluent discharge, the total river water mixing distance (with transect sampling), and 2 points downstream from this last area. The main parameters required determining field Rd of TE and RN and their geochemical modeling (Kd) were ac- quired. Filtered waters were analyzed for alkalinity, anions, cations, dissolved organic carbon (DOC), TE, and RN concentrations. Suspended particulate matter (SPM) was analyzed for particulate organic carbon (POC), TE and RN concentrations and mineralogical composition. Field Rd and Kd values are in good agreement for stable Cd, Cu, Ni, Pb and Zn and for 7Be. Conversely, measured field Rd for stable Ag, Ba, Sr, Co and Cs are systematically higher than modeled Kd values. Even if only the lowest possible values were obtained for 137Cs and 60Co Rd measurements, these estimated limits are higher than calculated Kd for 137Cs and in good agreement for 60Co. Finally, only two RN exhibit field Rd lower than calculated Kd: 234Th and 210Pb.Comparison of field Rd vs. modeled Kd values for TE and RN allows the identification, for each element, of the main involved adsorption phases and geochemical mechanisms controlling their fate and partitioning in river systems.
Published: 2020

46. A framework for pre-processing individual location telemetry data for freshwater fish in a river section

Author: Hervé Pella, Anthony Maire, Hervé Capra, Dominique Lamonica, Hilaire Drouineau, Riverly (Riverly), Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Institute of Landscape and Plant Ecology, University of Hohenheim, Stuttgart, Germany, Ecosystèmes aquatiques et changements globaux (UR EABX), and EDF R&D, LNHE (Laboratoire National d’Hydraulique et Environnement), HYNES (Irstea - EDF R&D), 6 quai Watier, Chatou Cedex 78401, France
Subjects: 0106 biological sciences, State-space representation, Computer science, Estimation theory, 010604 marine biology & hydrobiology, Ecological Modeling, Bayesian inference, State-space model, Missing data, computer.software_genre, 010603 evolutionary biology, 01 natural sciences, Switching behaviour, Animal location data, Trajectory, Parameter estimation, 14. Life underwater, Data mining, [SDE.BE]Environmental Sciences/Biodiversity and Ecology, Scale (map), Raw data, computer, Movement model, Interpolation
Abstract: International audience; Animal movement study often relies on individual tracking. The data scale (in time and space) varies according to the species, the environment where individuals live, or the exogenous processes that drive movement. To explore freshwater fish movement in rivers, fine-scale data are needed. Also, in rivers, recorded telemetry frequently shows missing data and location errors. The irregular time-steps, huge amount of data, environmental complexity (river section) and how fish move in such anisotropic environments undermine the use of statistical frameworks such as state-space models. To deal with these specificities, data pre-treatment can be required. We propose a generic method of telemetry data pre-processing, which can be transposed to other datasets. This framework includes interpolation to handle trajectories at fine time scales and performs data analysis within a state-space model. We combined analyses on observed and simulated data at various interpolation time-steps to choose the one that best preserves the general movement while reducing the total amount of data required. First, we directly compared raw and interpolated data, and the results of parameter inference of a simple state-space model using the interpolated data. The state-space model infers behavioural state based on speed and turning angle between successive locations in animal trajectories. We also included two additional variables computed from raw data: a quantitative indicator of the correspondence between the interpolated trajectory and the raw data, and the variance of turning angles of raw data within the interpolation time-step. We were finally able to determine the most appropriate time-step to obtain locations that were regularly spaced in time and to reduce the amount of data while maintaining the precision of the raw data. Computational time was reduced 12-fold by using a 30-second time-step to interpolate data simulated at 3-second intervals. The inclusion of the two variables derived from raw data compensated for the loss of information in interpolated trajectories and allowed more efficient discrimination between behaviours.
Published: 2020

47. Downstream erosion and deposition dynamics of fine suspended sediments due to dam flushing

Author: Magali Jodeau, Benoît Camenen, Michel Esteves, Germain Antoine, Julien Némery, Laboratoire National d’Hydraulique et Environnement (EDF R&D LNHE), EDF R&D (EDF R&D), EDF (EDF)-EDF (EDF), UMR LHSV (UMR LHSV), Avant création Cerema, Riverly (Riverly), Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP ), Université Grenoble Alpes (UGA), and ANR-18-CE01-0020,DEUFI,Détails de l'impact des inondations urbaines(2018)
Subjects: 010504 meteorology & atmospheric sciences, 0207 environmental engineering, Flux, 02 engineering and technology, Detailed data, Local mass balance, 01 natural sciences, Deposition (geology), [SPI.MECA.MEFL]Engineering Sciences [physics]/Mechanics [physics.med-ph]/Fluids mechanics [physics.class-ph], Hydrology (agriculture), Dam flushing, medicine, [SDU.STU.HY]Sciences of the Universe [physics]/Earth Sciences/Hydrology, 020701 environmental engineering, 0105 earth and related environmental sciences, Water Science and Technology, Hydrology, Sediment, Suspended sediment flux, 6. Clean water, 13. Climate action, River network, Erosion, Flushing, Environmental science, Suspended sediment concentration (SSC), medicine.symptom, Impounded Alpine river
Abstract: International audience; Fine sediment dynamics downstream dams is a key issue when dealing with environmental impact of hydraulic flushing. This paper presents an analysis of six field campaigns carried out during dam flushing events (in June 2006, 2007, 2009, 2010, 2011, and 2012) in the Arc- Isere river system in the Northern French Alps. Suspended sediment concentrations (SSC) and discharges were evaluated using direct measurements or/and 1D hydraulic modelling at up to 14 locations along the 120 kilometres-long river channel. The total suspended sediment flux (SSF) is analysed along the Arc and Isere rivers for each Arc dam flushing event. Uncertainties were quantified based on a propagation method of both measurement and modelling errors. The resulting confidence interval provides elements of discussion on the significance of the sediment mass balance between two consecutive measurement sites. Whereas the discharge time-series of each flushing event is roughly the same, the quantity of fine sediments removed from the reservoirs varied from 10,000 tons in 2007 to 40,000 tons in 2006. Also, a significant erosion is observed in the river system for some events (20,000 tons in 2007) while the SSF barely varied for other events (in 2009 and 2011). This detailed data set allows to identify specific locations in the river network where deposition or erosion occurred. This dynamics is closely related to both the hydrology in the upper Isere River and the morphology of the Arc and Isere rivers, which have been affected by the 2008 and 2010 floods.
Published: 2020

48. A new criterion for the evaluation of the velocity field for rainfall-runoff modelling using a shallow-water model

Author: Germain Antoine, Olivier Delestre, Florent Taccone, Nicole Goutal, Laboratoire National d’Hydraulique et Environnement (EDF R&D LNHE), EDF R&D (EDF R&D), EDF (EDF)-EDF (EDF), Laboratoire d'Hydraulique Saint-Venant / Saint-Venant laboratory for Hydraulics (Saint-Venant), École des Ponts ParisTech (ENPC)-Centre d'Etudes et d'Expertise sur les Risques, l'Environnement, la Mobilité et l'Aménagement (Cerema)-EDF R&D (EDF R&D), LJAD, Laboratoire Jean Alexandre Dieudonné (JAD), Université Côte d'Azur (UCA)-Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Centre National de la Recherche Scientifique (CNRS)-Université Côte d'Azur (UCA)-Université Nice Sophia Antipolis (... - 2019) (UNS), and COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Watershed, 010504 meteorology & atmospheric sciences, [SDE.IE]Environmental Sciences/Environmental Engineering, 0208 environmental biotechnology, Soil science, Hydrograph, 02 engineering and technology, 01 natural sciences, 6. Clean water, 020801 environmental engineering, [SPI.MECA.MEFL]Engineering Sciences [physics]/Mechanics [physics.med-ph]/Fluids mechanics [physics.class-ph], Waves and shallow water, Infiltration (hydrology), Test case, 13. Climate action, Vector field, Surface runoff, Shallow water equations, Geology, [MATH.MATH-NA]Mathematics [math]/Numerical Analysis [math.NA], 0105 earth and related environmental sciences, Water Science and Technology
Abstract: International audience; The aim of this work is to evaluate the accuracy of physically based models using the 2D Shallow Water Equations (SWE) for the simulation of rain-induced runoff. A key expectation of these models is to be able to reproduce properly both hydrograph at the outlet of the watershed and the associated velocity field within the spatial domain for a given rain event. However, this ability can be very challenging in mountainous environments, which include heterogeneous and high values of bottom slope and transient rain inputs. In this paper, we focused on both the error due to the numerical resolution of the SWE for low water depths runoff on steep slopes and that due to the physical representation of friction on the bottom for various water depth to roughness height ratios. Four test cases have been used, at different scales, to evaluate the model in comparison with experimental data. The first test case (from [Kirstetter et al., 2015]) was a rain induced flow in a straight channel. It allows to evaluate the error made for the chosen numerical resolution of the SWE and its impact on the velocity distribution in the domain (metric scale). A criterion defining an acceptable numerical error has been proposed. A second test case (from [Cea et al., 2014]), has been chosen for being also metric scaled and in the right range of the numerical error criterion. It allowed to evaluate the ability of a new friction law (adapted from [Lawrence, 1997]) to represent the measured velocity field in several inundation regimes at the metric scale. The third test case was a 40 m 2 real plot studied by [Tatard et al., 2008]. On this test case, measured velocities have been compared with the simulated ones. Thanks to an infiltration source term added to the mass conservation equation, hydrographs at the outlet of the plot have been well reproduced, as well as the main part (including the highest values) of the measured velocities. In particular, the velocities are well represented when the criterion given in the first test case is satisfied. Finally, the model is applied to a real watershed with an area of 1 km 2 on which hydrographs at the outlet have been successfully reproduced for two extreme rainy events [Le Bouteiller et al., 2015]. It appeared that both physical and numerical error were low in the hydrographic network and that the local velocities are correctly reproduced there, unlike in the hillslopes where the velocities are not well reproduced even if the mass fluxes are correct.
Published: 2020

49. Interpretation of interannual variability in long-term aquatic ecological surveys

Author: Bernard Cazelles, Hervé Capra, Sophie Cauvy-Fraunié, Martin Daufresne, Verena M. Trenkel, Jean-Michel Olivier, Nicolas Lamouroux, Anthony Maire, Jérémy Lobry, RiverLy (UR Riverly), Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA), Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER), Risques, Ecosystèmes, Vulnérabilité, Environnement, Résilience (RECOVER), Aix Marseille Université (AMU)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Laboratoire National d’Hydraulique et Environnement (EDF R&D LNHE), EDF R&D (EDF R&D), EDF (EDF)-EDF (EDF), Laboratoire d'Ecologie des Hydrosystèmes Naturels et Anthropisés (LEHNA), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-École Nationale des Travaux Publics de l'État (ENTPE)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Ecosystèmes aquatiques et changements globaux (UR EABX), Institut de biologie de l'ENS Paris (UMR 8197/1024) (IBENS), Département de Biologie - ENS Paris, École normale supérieure - Paris (ENS Paris)-École normale supérieure - Paris (ENS Paris)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Unité de modélisation mathématique et informatique des systèmes complexes [Bondy] (UMMISCO), Institut de la francophonie pour l'informatique-Université Cheikh Anta Diop [Dakar, Sénégal] (UCAD)-Université Gaston Bergé (Saint-Louis, Sénégal)-Universtié Yaoundé 1 [Cameroun]-Université Cadi Ayyad [Marrakech] (UCA)-Sorbonne Université (SU)-Institut de Recherche pour le Développement (IRD [France-Nord]), RiverLy - Fonctionnement des hydrosystèmes (RiverLy), Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Équipe 1 - Biodiversité et Adaptation dans les Hydrosystèmes (BAH), Université de Lyon-Université de Lyon-École Nationale des Travaux Publics de l'État (ENTPE)-Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-École Nationale des Travaux Publics de l'État (ENTPE)-Centre National de la Recherche Scientifique (CNRS), Institut de biologie de l'ENS Paris (IBENS), École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Université de Yaoundé I-Institut de la francophonie pour l'informatique-Université Cheikh Anta Diop [Dakar, Sénégal] (UCAD)-Université Gaston Bergé (Saint-Louis, Sénégal)-Université Cadi Ayyad [Marrakech] (UCA)-Sorbonne Université (SU)-Institut de Recherche pour le Développement (IRD [France-Nord]), ANR-11-LABX-0010,DRIIHM / IRDHEI,Dispositif de recherche interdisciplinaire sur les Interactions Hommes-Milieux(2011), Riverly (Riverly), Lyvet, Nathalie, Dispositif de recherche interdisciplinaire sur les Interactions Hommes-Milieux - - DRIIHM / IRDHEI2011 - ANR-11-LABX-0010 - LABX - VALID, École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS Paris), Institut de Recherche pour le Développement (IRD [France-Nord])-Institut de la francophonie pour l'informatique-Université Cheikh Anta Diop [Dakar, Sénégal] (UCAD)-Université Gaston Bergé (Saint-Louis, Sénégal)-Université Cadi Ayyad [Marrakech] (UCA)-Université de Yaoundé I-Sorbonne Université (SU), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-École Nationale des Travaux Publics de l'État (ENTPE)-Université Claude Bernard Lyon 1 (UCBL), and Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-École Nationale des Travaux Publics de l'État (ENTPE)
Subjects: 0106 biological sciences, Ecology, 010604 marine biology & hydrobiology, Interpretation (philosophy), Sampling (statistics), Aquatic Science, 010603 evolutionary biology, 01 natural sciences, Term (time), [SDE.BE] Environmental Sciences/Biodiversity and Ecology, 13. Climate action, Environmental science, 14. Life underwater, [SDE.BE]Environmental Sciences/Biodiversity and Ecology, Ecology, Evolution, Behavior and Systematics, ComputingMilieux_MISCELLANEOUS
Abstract: [Departement_IRSTEA]Eaux [TR1_IRSTEA]QUASARE [ADD1_IRSTEA]Systèmes aquatiques soumis à des pressions multiples; International audience; Long-term ecological surveys (LTES) often exhibit strong variability among sampling dates. The use and interpretation of such interannual variability is challenging due to the combination of multiple processes involved and sampling uncertainty. Here, we analysed the interannual variability in ~30 years of species-density (fish and invertebrate) and environmental observation time series in four aquatic-systems (stream, river, estuary, and marine continental shelf) with different sampling efforts to identify the information provided by this variability. We tested, using two empirical methods, whether we could observe simultaneous fluctuation between detrended time series corresponding to widely acknowledged assumptions about aquatic population dynamics: spatial effects, cohort effects, and environmental effects. We found a low number of significant results (36, 9, 0% for spatial, cohort, and environmental effects), suggesting that sampling uncertainty overrode the effects of biological processes. Our study does not question the relevance of LTES for detecting important trends, but clearly indicated that the statistical power to interpret interannual variations in aquatic-species densities is low, especially in large systems where the degree of sampling effort is always limited.
Published: 2020

50. The Navier-Stokes system with temperature and salinity for free surface flows Part I: Low-Mach approximation & layer-averaged formulation

Author: Boittin, Léa, Bouchut, François, Bristeau, Marie-Odile, Mangeney, Anne, Sainte-Marie, Jacques, Souillé, Fabien, Numerical Analysis, Geophysics and Ecology (ANGE), Inria de Paris, Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria)-Laboratoire Jacques-Louis Lions (LJLL (UMR_7598)), Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP), Laboratoire Analyse et Mathématiques Appliquées (LAMA), Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Centre National de la Recherche Scientifique (CNRS)-Université Gustave Eiffel, Centre d'Etudes et d'Expertise sur les Risques, l'Environnement, la Mobilité et l'Aménagement (Cerema), Institut de Physique du Globe de Paris, The authors acknowledge the Inria Project Lab 'Algae in Silico' for its financial support. This research is also supported by the ERC SLIDEQUAKES ERC-CG-2013-PE10-617472, Université Gustave Eiffel (UNIV GUSTAVE EIFFEL), Institut de Physique du Globe de Paris (IPGP), Institut national des sciences de l'Univers (INSU - CNRS)-IPG PARIS-Université de La Réunion (UR)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP), Laboratoire National d’Hydraulique et Environnement (EDF R&D LNHE), EDF R&D (EDF R&D), EDF (EDF)-EDF (EDF), The authors acknowledge the Inria Project Lab 'Algae in Silico' for its financial support. This research is also supported by the ERC SLIDEQUAKES ERC-CG-2013-PE10-617472., European Project: 617472,EC:FP7:ERC,ERC-2013-CoG,SLIDEQUAKE(2014), Université Paris Diderot - Paris 7 (UPD7)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Analyse et de Mathématiques Appliquées (LAMA), and Université Paris-Est Marne-la-Vallée (UPEM)-Fédération de Recherche Bézout-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Centre National de la Recherche Scientifique (CNRS)
Subjects: [SDU.OCEAN]Sciences of the Universe [physics]/Ocean, Atmosphere, [PHYS.MECA.MEFL]Physics [physics]/Mechanics [physics]/Mechanics of the fluids [physics.class-ph], Free surface flows, [INFO.INFO-MO]Computer Science [cs]/Modeling and Simulation, Physics::Fluid Dynamics, Low-Mach approximation, Free sur- face flows, Layer-averaged formulation, Compressible and incompressible fluids, [MATH.MATH-AP]Mathematics [math]/Analysis of PDEs [math.AP], Variable density flows, [PHYS.MECA.MEFL]Physics [physics]/Mechanics [physics]/Fluid mechanics [physics.class-ph], Navier-Stokes equations, [MATH.MATH-NA]Mathematics [math]/Numerical Analysis [math.NA]
Abstract: We are interested in free surface flows where density variations coming e.g. from temperature or salinity differences play a significant role in the hydrody-namic regime. In water, acoustic waves travel much faster than gravity and internal waves, hence the study of models arising from compressible fluid mechanics often requires a decoupling between these waves. Starting from the compressible Navier-Stokes system, we derive the so-called Navier-Stokes-Fourier system in an "incompressible" regime using the low-Mach scaling, hence filtering the acoustic waves, neglecting the density dependency on the fluid pressure but keeping its variations in terms of temperature and salinity. A slightly modified low-Mach asymptotics is proposed to obtain a model with thermo-mechanical compatibility. The case when the density depends only on the temperature is studied first. Then the variations of the fluid density with respect to temperature and salinity are 1 considered, and it seems to be the first time that salinity dependency is considered in this low Mach limit. We give a layer-averaged formulation of the obtained models in an hydrostatic context, allowing to derive numerical schemes endowed with strong stability properties that are presented in a companion paper. Several stability properties of the layer-averaged Navier-Stokes-Fourier system are proved.
Published: 2020

Catalog

Books, media, physical & digital resources

See catalog results

Searchworks

Select search scope, currently: Articles Catalog books, media & more in Jio Institute collections Articles journal articles & other e-resources

Search

Search Constraints

Refine your results

Search Limiters

Topic

Publication Year Range

Language

Publication Type

Journal

Region

Database

Publisher

248 results on '"Laboratoire National d’Hydraulique et Environnement (EDF R'

Search Results

Catalog

Select search scope, currently: Articles

Catalog

books, media & more in Jio Institute collections

Articles

journal articles & other e-resources