Articles | Volume 29, issue 23
https://doi.org/10.5194/hess-29-6885-2025
© Author(s) 2025. 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-29-6885-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Will groundwater-borne nutrients affect river eutrophication in the future? A multi-tracer study along the Elbe River
Julia Zill
CORRESPONDING AUTHOR
Dept. Catchment Hydrology, Helmholtz Centre for Environmental Research (UFZ), Halle (Saale), 06120, Germany
Axel Suckow
CSIRO Land and Water, Urrbrae (SA), 5064, Australia
Ulf Mallast
Dept. Monitoring- and Exploration Technologies, Helmholtz Centre for Environmental Research (UFZ), Leipzig, 04318, Germany
Jürgen Sültenfuß
Institute of Environmental Physics, University of Bremen, Otto-Hahn-Allee 1, 28359, Bremen, Germany
Axel Schmidt
Ref. G4 Radiology and Water Monitoring, Federal Institute of Hydrology (BfG), Koblenz 56068, Germany
Christian Siebert
CORRESPONDING AUTHOR
Dept. Catchment Hydrology, Helmholtz Centre for Environmental Research (UFZ), Halle (Saale), 06120, Germany
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EGUsphere, https://doi.org/10.5194/egusphere-2025-5666, https://doi.org/10.5194/egusphere-2025-5666, 2025
This preprint is open for discussion and under review for Hydrology and Earth System Sciences (HESS).
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Groundwater is Germany’s main source of drinking water but is under stress from climate change and growing use. We used a frequency domain approach to study how quickly groundwater reacts to changes in precipitation (recharge) by analyzing groundwater levels from almost 200 wells in southern Germany. Most systems responded within 50 to 300 days. Areas with slower response times tend to handle dry periods better. These results can help manage groundwater more safely in the future.
Céline Heuzé, Oliver Huhn, Maren Walter, Natalia Sukhikh, Salar Karam, Wiebke Körtke, Myriel Vredenborg, Klaus Bulsiewicz, Jürgen Sültenfuß, Ying-Chih Fang, Christian Mertens, Benjamin Rabe, Sandra Tippenhauer, Jacob Allerholt, Hailun He, David Kuhlmey, Ivan Kuznetsov, and Maria Mallet
Earth Syst. Sci. Data, 15, 5517–5534, https://doi.org/10.5194/essd-15-5517-2023, https://doi.org/10.5194/essd-15-5517-2023, 2023
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Gases dissolved in the ocean water not used by the ecosystem (or "passive tracers") are invaluable to track water over long distances and investigate the processes that modify its properties. Unfortunately, especially so in the ice-covered Arctic Ocean, such gas measurements are sparse. We here present a data set of several passive tracers (anthropogenic gases, noble gases and their isotopes) collected over the full ocean depth, weekly, during the 1-year drift in the Arctic during MOSAiC.
Damian L. Arévalo-Martínez, Amir Haroon, Hermann W. Bange, Ercan Erkul, Marion Jegen, Nils Moosdorf, Jens Schneider von Deimling, Christian Berndt, Michael Ernst Böttcher, Jasper Hoffmann, Volker Liebetrau, Ulf Mallast, Gudrun Massmann, Aaron Micallef, Holly A. Michael, Hendrik Paasche, Wolfgang Rabbel, Isaac Santos, Jan Scholten, Katrin Schwalenberg, Beata Szymczycha, Ariel T. Thomas, Joonas J. Virtasalo, Hannelore Waska, and Bradley A. Weymer
Biogeosciences, 20, 647–662, https://doi.org/10.5194/bg-20-647-2023, https://doi.org/10.5194/bg-20-647-2023, 2023
Short summary
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Groundwater flows at the land–ocean transition and the extent of freshened groundwater below the seafloor are increasingly relevant in marine sciences, both because they are a highly uncertain term of biogeochemical budgets and due to the emerging interest in the latter as a resource. Here, we discuss our perspectives on future research directions to better understand land–ocean connectivity through groundwater and its potential responses to natural and human-induced environmental changes.
Helene M. Hoffmann, Mackenzie M. Grieman, Amy C. F. King, Jenna A. Epifanio, Kaden Martin, Diana Vladimirova, Helena V. Pryer, Emily Doyle, Axel Schmidt, Jack D. Humby, Isobel F. Rowell, Christoph Nehrbass-Ahles, Elizabeth R. Thomas, Robert Mulvaney, and Eric W. Wolff
Clim. Past, 18, 1831–1847, https://doi.org/10.5194/cp-18-1831-2022, https://doi.org/10.5194/cp-18-1831-2022, 2022
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The WACSWAIN project (WArm Climate Stability of the West Antarctic ice sheet in the last INterglacial) investigates the fate of the West Antarctic Ice Sheet during the last warm period on Earth (115 000–130 000 years before present). Within this framework an ice core was recently drilled at Skytrain Ice Rise. In this study we present a stratigraphic chronology of that ice core based on absolute age markers and annual layer counting for the last 2000 years.
Amanda T. Nylund, Lars Arneborg, Anders Tengberg, Ulf Mallast, and Ida-Maja Hassellöv
Ocean Sci., 17, 1285–1302, https://doi.org/10.5194/os-17-1285-2021, https://doi.org/10.5194/os-17-1285-2021, 2021
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Acoustic and satellite observations of turbulent ship wakes show that ships can mix the water column down to 30 m depth and that a temperature signature of the wake can last for tens of kilometres after ship passage. Turbulent wakes deeper than 12 m were frequently detected, which is deeper than previously reported. The observed extent of turbulent ship wakes implies that in areas with intensive ship traffic, ship mixing should be considered when assessing environmental impacts from shipping.
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Short summary
Groundwater in agricultural regions can transport nutrients and contaminants into rivers, affecting water quality. This study examines nutrient flux in the German Elbe River using multi-environmental tracers. Groundwater takes a few decades to reach the river, mostly infiltrating after 1985. This means that massive nutrient inputs from past fertilization have peaked and will decline in the future. These findings guide management strategies to reduce eutrophication and protect aquatic ecosystems.
Groundwater in agricultural regions can transport nutrients and contaminants into rivers,...