Articles | Volume 29, issue 20
https://doi.org/10.5194/hess-29-5835-2025
© 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-29-5835-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
28 Oct 2025
Research article |
| 28 Oct 2025
| 28 Oct 2025
Changes in water quality and ecosystem processes at extreme summer low flow of 2018 with high-frequency sensors
Department of Aquatic Ecosystem Analysis, Helmholtz Centre for Environmental Research – UFZ, Brueckstrasse 3a, 39114 Magdeburg, Germany
Chair of Hydrology and River Basin Management, Technical University of Munich, Arcisstrasse 21, 80333 Munich, Germany
Dietrich Borchardt
Department of Aquatic Ecosystem Analysis, Helmholtz Centre for Environmental Research – UFZ, Brueckstrasse 3a, 39114 Magdeburg, Germany
Michael Rode
Department of Aquatic Ecosystem Analysis, Helmholtz Centre for Environmental Research – UFZ, Brueckstrasse 3a, 39114 Magdeburg, Germany
Institute of Environmental Science and Geography, University of Potsdam, Karl-Liebknecht-Strasse 24–25, 14476 Potsdam-Golm, Germany
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Short summary
Climate change is increasing low flows, yet how streams respond remains poorly understood. Using sensors in a German stream during the extreme 2018 drought, we found hotter water, more algae, and lower oxygen and nitrate levels. Daily oxygen swings intensified, and algae on the riverbed boosted gross primary productivity. Nitrate removal got more efficient. These changes highlight risks to water quality and ecosystems as droughts worsen, aiding efforts to protect rivers in a warming world.
Climate change is increasing low flows, yet how streams respond remains poorly understood. Using...
