Articles | Volume 30, issue 13
https://doi.org/10.5194/hess-30-4209-2026
© 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-30-4209-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
06 Jul 2026
Research article |
| 06 Jul 2026
| 06 Jul 2026
Combining traditional nutrient load analysis with storm hydrograph separation reveals concealed patterns in event-driven nutrient export in a rural headwater catchment
Department of Hydrology and Substance Balance, University of Kassel, Kassel, 34125, Germany
Caroline Spill
Department of Hydrology and Substance Balance, University of Kassel, Kassel, 34125, Germany
Matthias Gassmann
Department of Hydrology and Substance Balance, University of Kassel, Kassel, 34125, Germany
Related authors
Lukas Ditzel, Caroline Spill, and Matthias Gassmann
EGUsphere, https://doi.org/10.5194/egusphere-2024-230, https://doi.org/10.5194/egusphere-2024-230, 2024
Preprint archived
Short summary
Short summary
High temporal resolution in-situ measurements were used to detect changes in the patterns of dissolved organic carbon (DOC) quality and DOC export. DOC export dynamics shows the yearly DOC export is by a factor of ten smaller than expected. Hysteresis analysis implicates an activation of distant DOC sources during events in winter. Changes in the DOC quality seems to be controlled by factors such as season and the change of land use especially the rotation of crops on the near river farmlands.
Lukas Ditzel, Caroline Spill, and Matthias Gassmann
EGUsphere, https://doi.org/10.5194/egusphere-2024-230, https://doi.org/10.5194/egusphere-2024-230, 2024
Preprint archived
Short summary
Short summary
High temporal resolution in-situ measurements were used to detect changes in the patterns of dissolved organic carbon (DOC) quality and DOC export. DOC export dynamics shows the yearly DOC export is by a factor of ten smaller than expected. Hysteresis analysis implicates an activation of distant DOC sources during events in winter. Changes in the DOC quality seems to be controlled by factors such as season and the change of land use especially the rotation of crops on the near river farmlands.
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Short summary
The analysis of nutrient dynamics during precipitation events using normalised cumulative loads (NCL) is a classic and frequently used method of water quality analysis. Our approach combines the classical pollutograph with hydrograph separation using stable water isotopes. The pollutograph is set up for each of the separated runoff components (pre-event water and event water) and the export dynamics of the runoff components of an event are compared.
The analysis of nutrient dynamics during precipitation events using normalised cumulative loads...
