Articles | Volume 30, issue 6
https://doi.org/10.5194/hess-30-1523-2026
© Author(s) 2026. 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-30-1523-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Different tracer, different bias: using radon to reveal flow paths beyond the Window of Detection
Johanna Bacher
Department of Geosciences, University of Tübingen, Tübingen, Germany
Department of Geography, University of Bonn, Bonn, Germany
Julian Klaus
Department of Geography, University of Bonn, Bonn, Germany
Adam S. Ward
Department of Biological and Ecological Engineering, Oregon State University, Corvallis, OR, USA
Jasmine Krause
Department of Biological and Ecological Engineering, Oregon State University, Corvallis, OR, USA
Catalina Segura
Forest Engineering, Resources, and Management, Oregon State University, Corvallis, OR, USA
Department of Geography, University of Bonn, Bonn, Germany
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Short summary
Understanding solute transport often relies on slug tracer experiments. These experiments are biassed toward capturing faster flow paths and miss longer timescales. We explore integrating a slug-injected tracer with naturally occurring radon to quantify flow paths across different timescales at the reach scale. We show that jointly calibrating a transient storage model with both tracers strengthens parameter constraints and improves solute transport estimates in future studies.
Understanding solute transport often relies on slug tracer experiments. These experiments are...