Articles | Volume 25, issue 5
https://doi.org/10.5194/hess-25-2491-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/hess-25-2491-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Spatio-temporal controls of C–N–P dynamics across headwater catchments of a temperate agricultural region from public data analysis
Stella Guillemot
UMR SAS, INRAE, Institut Agro, 35000 Rennes, France
Université de Tours, EA 6293 GéHCO, 37200 Tours, France
UMR SAS, INRAE, Institut Agro, 35000 Rennes, France
Chantal Gascuel-Odoux
UMR SAS, INRAE, Institut Agro, 35000 Rennes, France
Gérard Gruau
OSUR, Geosciences Rennes, CNRS, Université Rennes 1, 35000 Rennes, France
Antoine Casquin
UMR SAS, INRAE, Institut Agro, 35000 Rennes, France
Florence Curie
Université de Tours, EA 6293 GéHCO, 37200 Tours, France
Camille Minaudo
EPFL, Physics of Aquatic Systems Laboratory, 1015 Lausanne,
Switzerland
Laurent Strohmenger
UMR SAS, INRAE, Institut Agro, 35000 Rennes, France
Florentina Moatar
INRAE, RIVERLY, 69625 Villeurbanne, France
Université de Tours, EA 6293 GéHCO, 37200 Tours, France
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Guillaume Evin, Benoit Hingray, Guillaume Thirel, Agnès Ducharne, Laurent Strohmenger, Lola Corre, Yves Tramblay, Jean-Philippe Vidal, Jérémie Bonneau, François Colleoni, Joël Gailhard, Florence Habets, Frédéric Hendrickx, Louis Héraut, Peng Huang, Matthieu Le Lay, Claire Magand, Paola Marson, Céline Monteil, Simon Munier, Alix Reverdy, Jean-Michel Soubeyroux, Yoann Robin, Jean-Pierre Vergnes, Mathieu Vrac, and Eric Sauquet
EGUsphere, https://doi.org/10.5194/egusphere-2025-2727, https://doi.org/10.5194/egusphere-2025-2727, 2025
This preprint is open for discussion and under review for Hydrology and Earth System Sciences (HESS).
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Explore2 provides hydrological projections for 1,735 French catchments. Using QUALYPSO, this study assesses uncertainties, including internal variability. By the end of the century, low flows are projected to decline in southern France under high emissions, while other indicators remain uncertain. Emission scenarios and regional climate models are key uncertainty sources. Internal variability is often as large as climate-driven changes.
Camille Minaudo, Andras Abonyi, Carles Alcaraz, Jacob Diamond, Nicholas J. K. Howden, Michael Rode, Estela Romero, Vincent Thieu, Fred Worrall, Qian Zhang, and Xavier Benito
Earth Syst. Sci. Data, 17, 3411–3430, https://doi.org/10.5194/essd-17-3411-2025, https://doi.org/10.5194/essd-17-3411-2025, 2025
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Many waterbodies undergo nutrient decline, called oligotrophication, globally, but a comprehensive dataset to understand ecosystem responses is lacking. The OLIGOTREND database comprises multi-decadal chlorophyll a and nutrient time series from rivers, lakes, and estuaries with 4.3 million observations from 1894 unique measurement locations. The database provides empirical evidence for oligotrophication responses with a spatial and temporal coverage that exceeds previous efforts.
Nicolai Brekenfeld, Solenn Cotel, Mikael Faucheux, Colin Fourtet, Yannick Hamon, Patrice Petitjean, Arnaud Blanchouin, Celine Bouillis, Marie-Claire Pierret, Hocine Henine, Anne-Catherine Pierson-Wickmann, Sophie Guillon, Paul Floury, and Ophelie Fovet
Hydrol. Earth Syst. Sci., 29, 2615–2631, https://doi.org/10.5194/hess-29-2615-2025, https://doi.org/10.5194/hess-29-2615-2025, 2025
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In the last decade, the development of on-site field laboratories to measure water chemistry at sub-hourly measurement intervals has drastically advanced, while there is no literature that provides detailed technical, organisational and operational guidelines in running such equipment. Based on our experiences of running three French field laboratories over 7 years, we share the main stages in the deployment of this tool in the field, the difficulties encountered and the proposed solutions.
Eric Sauquet, Guillaume Evin, Sonia Siauve, Ryma Aissat, Patrick Arnaud, Maud Bérel, Jérémie Bonneau, Flora Branger, Yvan Caballero, François Colléoni, Agnès Ducharne, Joël Gailhard, Florence Habets, Frédéric Hendrickx, Louis Héraut, Benoît Hingray, Peng Huang, Tristan Jaouen, Alexis Jeantet, Sandra Lanini, Matthieu Le Lay, Claire Magand, Louise Mimeau, Céline Monteil, Simon Munier, Charles Perrin, Olivier Robelin, Fabienne Rousset, Jean-Michel Soubeyroux, Laurent Strohmenger, Guillaume Thirel, Flore Tocquer, Yves Tramblay, Jean-Pierre Vergnes, and Jean-Philippe Vidal
EGUsphere, https://doi.org/10.5194/egusphere-2025-1788, https://doi.org/10.5194/egusphere-2025-1788, 2025
This preprint is open for discussion and under review for Hydrology and Earth System Sciences (HESS).
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The Explore2 project has provided an unprecedented set of hydrological projections in terms of the number of hydrological models used and the spatial and temporal resolution. The results have been made available through various media. Under the high-emission scenario, the hydrological models mostly agree on the decrease in seasonal flows in the south of France, confirming its hotspot status, and on the decrease in summer flows throughout France, with the exception of the northern part of France.
Yves Tramblay, Guillaume Thirel, Laurent Strohmenger, Guillaume Evin, Lola Corre, Louis Heraut, and Eric Sauquet
EGUsphere, https://doi.org/10.5194/egusphere-2025-1635, https://doi.org/10.5194/egusphere-2025-1635, 2025
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How climate change impacts floods in France? Using simulations for 3000 rivers in climate projections, results show that flood trends vary depending on the region. In the north, floods may become more severe, but in many other areas, the trends are mixed. Floods from intense rainfall are becoming more frequent, while snowmelt floods are strongly decreasing. Overall, the study shows that understanding what causes floods is key to predicting how they are likely to change with the climate.
An Truong Nguyen, Gwenaël Abril, Jacob S. Diamond, Raphaël Lamouroux, Cécile Martinet, and Florentina Moatar
EGUsphere, https://doi.org/10.5194/egusphere-2025-1478, https://doi.org/10.5194/egusphere-2025-1478, 2025
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This 32-year study of France’s Loire River shows cleaner water reduced carbon dioxide emissions by 62 %, despite increased contributions from aquatic plant activity. Seasonal emissions were higher in autumn than spring, while long-term declines were driven by reduced external carbon inputs from groundwater and soils. Results highlight how ecosystem changes influence rivers' role in global carbon cycles and climate management.
Jordy Salmon-Monviola, Ophélie Fovet, and Markus Hrachowitz
Hydrol. Earth Syst. Sci., 29, 127–158, https://doi.org/10.5194/hess-29-127-2025, https://doi.org/10.5194/hess-29-127-2025, 2025
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To increase the predictive power of hydrological models, it is necessary to improve their consistency, i.e. their physical realism, which is measured by the ability of the model to reproduce observed system dynamics. Using a model to represent the dynamics of water and nitrate and dissolved organic carbon concentrations in an agricultural catchment, we showed that using solute-concentration data for calibration is useful to improve the hydrological consistency of the model.
Nicolai Brekenfeld, Solenn Cotel, Mikaël Faucheux, Paul Floury, Colin Fourtet, Jérôme Gaillardet, Sophie Guillon, Yannick Hamon, Hocine Henine, Patrice Petitjean, Anne-Catherine Pierson-Wickmann, Marie-Claire Pierret, and Ophélie Fovet
Hydrol. Earth Syst. Sci., 28, 4309–4329, https://doi.org/10.5194/hess-28-4309-2024, https://doi.org/10.5194/hess-28-4309-2024, 2024
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The proposed methodology consists of simultaneously analysing the concentration variation of solute pairs during a storm event by plotting the concentration variation of one solute against the variation of another solute. This can reveal whether two or more end-members contribute to streamflow during a storm event. Furthermore, the variation of the solute ratios during the events can indicate which catchment processes are dominant and which are negligible.
Giulia Bruno, Laurent Strohmenger, and Doris Duethmann
EGUsphere, https://doi.org/10.5194/egusphere-2024-2678, https://doi.org/10.5194/egusphere-2024-2678, 2024
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Decreases in streamflow during dry periods threaten ecosystems and society, and increases in evapotranspiration may contribute to them. From data for small catchments in Germany, summer low flows decreased over 1970–2019 and increases in evapotranspiration relevantly contributed. Stronger-than-expected decreases in streamflow during the 1989–1993 drought occurred in catchments with increases in evapotranspiration. Increases in evapotranspiration need full consideration for streamflow prediction.
Laurent Strohmenger, Eric Sauquet, Claire Bernard, Jérémie Bonneau, Flora Branger, Amélie Bresson, Pierre Brigode, Rémy Buzier, Olivier Delaigue, Alexandre Devers, Guillaume Evin, Maïté Fournier, Shu-Chen Hsu, Sandra Lanini, Alban de Lavenne, Thibault Lemaitre-Basset, Claire Magand, Guilherme Mendoza Guimarães, Max Mentha, Simon Munier, Charles Perrin, Tristan Podechard, Léo Rouchy, Malak Sadki, Myriam Soutif-Bellenger, François Tilmant, Yves Tramblay, Anne-Lise Véron, Jean-Philippe Vidal, and Guillaume Thirel
Hydrol. Earth Syst. Sci., 27, 3375–3391, https://doi.org/10.5194/hess-27-3375-2023, https://doi.org/10.5194/hess-27-3375-2023, 2023
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We present the results of a large visual inspection campaign of 674 streamflow time series in France. The objective was to detect non-natural records resulting from instrument failure or anthropogenic influences, such as hydroelectric power generation or reservoir management. We conclude that the identification of flaws in flow time series is highly dependent on the objectives and skills of individual evaluators, and we raise the need for better practices for data cleaning.
Hanieh Seyedhashemi, Florentina Moatar, Jean-Philippe Vidal, and Dominique Thiéry
Earth Syst. Sci. Data, 15, 2827–2839, https://doi.org/10.5194/essd-15-2827-2023, https://doi.org/10.5194/essd-15-2827-2023, 2023
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This paper presents a past and future dataset of daily time series of discharge and stream temperature for 52 278 reaches over the Loire River basin (100 000 km2) in France, using thermal and hydrological models. Past data are provided over 1963–2019. Future data are available over the 1976–2100 period under different future climate change models (warm and wet, intermediate, and hot and dry) and scenarios (optimistic, intermediate, and pessimistic).
Baibaswata Bhaduri, Ophelie Fovet, Sekhar Muddu, and Laurent Ruiz
Hydrol. Earth Syst. Sci. Discuss., https://doi.org/10.5194/hess-2023-112, https://doi.org/10.5194/hess-2023-112, 2023
Publication in HESS not foreseen
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Lumped conceptual groundwater transit time models are widely used for their computational simplicity. But their parameters being empirical, these models are often criticized for their calibration reliance. This study mathematically links lumped conceptual parameters to measurable hydrodynamic properties of a groundwater catchment. This kind of direct parameterization gives lumped models a forward modelling potential, and also improves the choice of parameter constraints in calibration exercises.
Artur Safin, Damien Bouffard, Firat Ozdemir, Cintia L. Ramón, James Runnalls, Fotis Georgatos, Camille Minaudo, and Jonas Šukys
Geosci. Model Dev., 15, 7715–7730, https://doi.org/10.5194/gmd-15-7715-2022, https://doi.org/10.5194/gmd-15-7715-2022, 2022
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Reconciling the differences between numerical model predictions and observational data is always a challenge. In this paper, we investigate the viability of a novel approach to the calibration of a three-dimensional hydrodynamic model of Lake Geneva, where the target parameters are inferred in terms of distributions. We employ a filtering technique that generates physically consistent model trajectories and implement a neural network to enable bulk-to-skin temperature conversion.
Aurélien Beaufort, Jacob S. Diamond, Eric Sauquet, and Florentina Moatar
Hydrol. Earth Syst. Sci., 26, 3477–3495, https://doi.org/10.5194/hess-26-3477-2022, https://doi.org/10.5194/hess-26-3477-2022, 2022
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We developed one of the largest stream temperature databases to calculate a simple, ecologically relevant metric – the thermal peak – that captures the magnitude of summer thermal extremes. Using statistical models, we extrapolated the thermal peak to nearly every stream in France, finding the hottest thermal peaks along large rivers without forested riparian zones and groundwater inputs. Air temperature was a poor proxy for the thermal peak, highlighting the need to grow monitoring networks.
Hanieh Seyedhashemi, Jean-Philippe Vidal, Jacob S. Diamond, Dominique Thiéry, Céline Monteil, Frédéric Hendrickx, Anthony Maire, and Florentina Moatar
Hydrol. Earth Syst. Sci., 26, 2583–2603, https://doi.org/10.5194/hess-26-2583-2022, https://doi.org/10.5194/hess-26-2583-2022, 2022
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Stream temperature appears to be increasing globally, but its rate remains poorly constrained due to a paucity of long-term data. Using a thermal model, this study provides a large-scale understanding of the evolution of stream temperature over a long period (1963–2019). This research highlights that air temperature and streamflow can exert joint influence on stream temperature trends, and riparian shading in small mountainous streams may mitigate warming in stream temperatures.
Nataline Simon, Olivier Bour, Mikaël Faucheux, Nicolas Lavenant, Hugo Le Lay, Ophélie Fovet, Zahra Thomas, and Laurent Longuevergne
Hydrol. Earth Syst. Sci., 26, 1459–1479, https://doi.org/10.5194/hess-26-1459-2022, https://doi.org/10.5194/hess-26-1459-2022, 2022
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Groundwater discharge into streams plays a major role in the preservation of stream ecosystems. There were two complementary methods, both based on the use of the distributed temperature sensing technology, applied in a headwater catchment. Measurements allowed us to characterize the spatial and temporal patterns of groundwater discharge and quantify groundwater inflows into the stream, opening very promising perspectives for a novel characterization of the groundwater–stream interface.
Danlu Guo, Camille Minaudo, Anna Lintern, Ulrike Bende-Michl, Shuci Liu, Kefeng Zhang, and Clément Duvert
Hydrol. Earth Syst. Sci., 26, 1–16, https://doi.org/10.5194/hess-26-1-2022, https://doi.org/10.5194/hess-26-1-2022, 2022
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We investigate the impact of baseflow contribution on concentration–flow (C–Q) relationships across the Australian continent. We developed a novel Bayesian hierarchical model for six water quality variables across 157 catchments that span five climate zones. For sediments and nutrients, the C–Q slope is generally steeper for catchments with a higher median and a greater variability of baseflow contribution, highlighting the key role of variable flow pathways in particulate and solute export.
Justine Louis, Anniet M. Laverman, Emilie Jardé, Alexandrine Pannard, Marine Liotaud, Françoise Andrieux-Loyer, Gérard Gruau, Florian Caradec, Emilie Rabiller, Nathalie Lebris, and Laurent Jeanneau
Biogeosciences Discuss., https://doi.org/10.5194/bg-2021-318, https://doi.org/10.5194/bg-2021-318, 2021
Preprint withdrawn
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This work has described the variability in sedimentary organic matter composition through a broad sampling campaign of marine mudflats at the regional scale (Brittany Region), and made the link with sediment potential biodegradability and nutrient release. In these coastal ecosystems affected by the eutrophication, the potential impact of human activities on the nutrient dynamics at the sediment-water interface was highlighted.
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Short summary
This study investigates the drivers of spatial variations in stream water quality in poorly studied headwater catchments and includes multiple elements involved in major water quality issues, such as eutrophication. We used a regional public dataset of monthly stream water concentrations monitored for 10 years over 185 agricultural catchments. We found a spatial and seasonal opposition between carbon and nitrogen concentrations, while phosphorus concentrations showed another spatial pattern.
This study investigates the drivers of spatial variations in stream water quality in poorly...