Articles | Volume 18, issue 16
https://doi.org/10.5194/bg-18-4705-2021
© 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/bg-18-4705-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
18 Aug 2021
Research article |
| 18 Aug 2021
| 18 Aug 2021
Diel patterns in stream nitrate concentration produced by in-stream processes
Jan Greiwe
CORRESPONDING AUTHOR
Hydrology, University of Freiburg, Friedrichstraße 39, 79098
Freiburg, Germany
Markus Weiler
Hydrology, University of Freiburg, Friedrichstraße 39, 79098
Freiburg, Germany
Jens Lange
Hydrology, University of Freiburg, Friedrichstraße 39, 79098
Freiburg, Germany
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This preprint is open for discussion and under review for Hydrology and Earth System Sciences (HESS).
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Using a dense 400 sensor network over 2.5 years, we studied how tree types influence forest soil moisture. We found soil moisture varies largely in space and time. In pure tree plots, the moisture variability peaks during intermediate wetness – when vegetation influence is strongest – but remains low during dry and wet phases. Consistently wet and dry zones indicate that spatial pattern are temporally stable. This work highlights small-scale spatiotemporal variability of forest water fluxes.
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This preprint is open for discussion and under review for Hydrology and Earth System Sciences (HESS).
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When it rains, much of the water reaching a stream has been stored in the soil for a long time, but why was unclear. We sprinkled two forested slopes with labelled water and used electrical imaging to watch it move. Only a small share moved quickly to the slope base; most of the outflow was older water pushed out by the pressure of the new rain. Much of the new water stayed in the topsoil and was released weeks later, affecting how soils carry nutrients and pollutants to streams.
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Hydrol. Earth Syst. Sci., 30, 4405–4436, https://doi.org/10.5194/hess-30-4405-2026, https://doi.org/10.5194/hess-30-4405-2026, 2026
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Subsurface stormflow (SSF) is a key runoff mechanism in upland environments. The analysis of SSF at two trenched hillslopes showed that SSF volume was controlled by total rainfall and initial wetness. Peakflow depended on rainfall amount, with initial wetness and rainfall intensity being important for small and large events, respectively. The rate at which SSF increased was linked to rainfall intensity and amount.
Heinke Paulsen and Markus Weiler
Hydrol. Earth Syst. Sci., 30, 4305–4319, https://doi.org/10.5194/hess-30-4305-2026, https://doi.org/10.5194/hess-30-4305-2026, 2026
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Using 12 Forest floor (FF) lysimeters at three beech‑dominated sites, we recorded 1570 rain events and measured throughfall, drainage, and evaporation. Initial retention depended on pre‑event moisture, not litter thickness. Low‑intensity, long‑duration rains filled the FF more efficiently than brief, intense storms. Evaporation was low and consistent across sites, showing the FF protects the soil. Spatial data revealed frequent water redistribution, creating heterogeneous flow paths.
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Hydrol. Earth Syst. Sci., 30, 3245–3261, https://doi.org/10.5194/hess-30-3245-2026, https://doi.org/10.5194/hess-30-3245-2026, 2026
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Hydrol. Earth Syst. Sci., 30, 779–795, https://doi.org/10.5194/hess-30-779-2026, https://doi.org/10.5194/hess-30-779-2026, 2026
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Jonas Pyschik and Markus Weiler
Hydrol. Earth Syst. Sci., 30, 485–501, https://doi.org/10.5194/hess-30-485-2026, https://doi.org/10.5194/hess-30-485-2026, 2026
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Yining Zang, Pauline C. Treble, Kei Yoshimura, Jayson Gabriel Pinza, Fengbo Zhang, Kübra Özdemir Çallı, Xiaojun Mei, Admin Husic, Alena Gessert, Andrej Stroj, Bartolomé Andreo, Bernard Ladouche, Christine Stumpp, Diana Mance, Eleni Zagana, Fen Huang, Giuseppe Sappa, Harald Kunstmann, Heike Brielmann, Hong Zhou, Huaying Wu, Jakob Garvelmann, James Berglund, Jean-Baptiste Charlier, Jens Lange, Juan Antonio Barberá Fornell, Junbing Pu, Konstantina Katsanou, Kun Ren, Laura Toran, Laurence Gill, Maria Filippini, Martin Kralik, Matías Mudarra Martínez, Min Zhao, Mingming Luo, Nico Goldscheider, Nikolaos Lambrakis, Pantaleone De Vita, Qiong Xiao, Shi Yu, Silvia Iacurto, Silvio Coda, Ted McCormack, Vincenzo Allocca, W. George Darling, Walter D’Alessandro, Xulei Guo, Yundi Hu, Zhijun Wang, Eva Kaminsky, Jiří Faimon, Marek Lang, Pavel Pracný, and Andreas Hartmann
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Hydrol. Earth Syst. Sci., 29, 2309–2319, https://doi.org/10.5194/hess-29-2309-2025, https://doi.org/10.5194/hess-29-2309-2025, 2025
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Jonas Pyschik, Stefan Seeger, Barbara Herbstritt, and Markus Weiler
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Barbara Herbstritt, Benjamin Gralher, Stefan Seeger, Michael Rinderer, and Markus Weiler
Hydrol. Earth Syst. Sci., 27, 3701–3718, https://doi.org/10.5194/hess-27-3701-2023, https://doi.org/10.5194/hess-27-3701-2023, 2023
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We present a method to collect water vapor samples into bags in the field without an in-field analyser, followed by isotope analysis in the lab. This new method resolves even fine-scaled natural isotope variations. It combines low-cost and lightweight components for maximum spatial and temporal flexibility regarding environmental setups. Hence, it allows for sampling even in terrains that are rather difficult to access, enabling future extended isotope datasets in soil sciences and ecohydrology.
Stefan Seeger and Markus Weiler
Hydrol. Earth Syst. Sci., 27, 3393–3404, https://doi.org/10.5194/hess-27-3393-2023, https://doi.org/10.5194/hess-27-3393-2023, 2023
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This study proposes a low-budget method to quantify the radial distribution of water transport velocities within trees at a high spatial resolution. We observed a wide spread of water transport velocities within a tree stem section, which were on average 3 times faster than the flux velocity. The distribution of transport velocities has implications for studies that use water isotopic signatures to study root water uptake and usually assume uniform or even implicitly infinite velocities.
Andreas Hänsler and Markus Weiler
Hydrol. Earth Syst. Sci., 26, 5069–5084, https://doi.org/10.5194/hess-26-5069-2022, https://doi.org/10.5194/hess-26-5069-2022, 2022
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Spatially explicit quantification of design storms is essential for flood risk assessment and planning. However, available datasets are mainly based on spatially interpolated station-based design storms. Since the spatial interpolation of the data inherits a large potential for uncertainty, we develop an approach to be able to derive spatially explicit design storms on the basis of weather radar data. We find that our approach leads to an improved spatial representation of design storms.
Anne Hartmann, Markus Weiler, Konrad Greinwald, and Theresa Blume
Hydrol. Earth Syst. Sci., 26, 4953–4974, https://doi.org/10.5194/hess-26-4953-2022, https://doi.org/10.5194/hess-26-4953-2022, 2022
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Analyzing the impact of soil age and rainfall intensity on vertical subsurface flow paths in calcareous soils, with a special focus on preferential flow occurrence, shows how water flow paths are linked to the organization of evolving landscapes. The observed increase in preferential flow occurrence with increasing moraine age provides important but rare data for a proper representation of hydrological processes within the feedback cycle of the hydro-pedo-geomorphological system.
Nils Hinrich Kaplan, Theresa Blume, and Markus Weiler
Hydrol. Earth Syst. Sci., 26, 2671–2696, https://doi.org/10.5194/hess-26-2671-2022, https://doi.org/10.5194/hess-26-2671-2022, 2022
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This study is analyses how characteristics of precipitation events and soil moisture and temperature dynamics during these events can be used to model the associated streamflow responses in intermittent streams. The models are used to identify differences between the dominant controls of streamflow intermittency in three distinct geologies of the Attert catchment, Luxembourg. Overall, soil moisture was found to be the most important control of intermittent streamflow in all geologies.
Benjamin Gralher, Barbara Herbstritt, and Markus Weiler
Hydrol. Earth Syst. Sci., 25, 5219–5235, https://doi.org/10.5194/hess-25-5219-2021, https://doi.org/10.5194/hess-25-5219-2021, 2021
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We scrutinized the quickest currently available method for stable isotope analysis of matrix-bound water. Simulating common procedures, we demonstrated the limits of certain materials currently used and identified a reliable and cost-efficient alternative. Further, we calculated the optimum proportions of important protocol aspects critical for precise and accurate analyses. Our unifying protocol suggestions increase data quality and comparability as well as the method's general applicability.
Felicia Linke, Oliver Olsson, Frank Preusser, Klaus Kümmerer, Lena Schnarr, Marcus Bork, and Jens Lange
Hydrol. Earth Syst. Sci., 25, 4495–4512, https://doi.org/10.5194/hess-25-4495-2021, https://doi.org/10.5194/hess-25-4495-2021, 2021
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We used a two-step approach with limited sampling effort in existing storm water infrastructure to illustrate the risk of biocide emission in a 2 ha urban area 13 years after construction had ended. First samples at a swale confirmed the overall relevance of biocide pollution. Then we identified sources where biocides were used for film protection and pathways where transformation products were formed. Our results suggest that biocide pollution is a also continuous risk in aging urban areas.
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Short summary
We analyzed variability in diel nitrate patterns at three locations in a lowland stream. Comparison of time lags between monitoring sites with water travel time indicated that diel patterns were created by in-stream processes rather than transported downstream from an upstream point of origin. Most of the patterns (70 %) could be explained by assimilatory nitrate uptake. The remaining patterns suggest seasonally varying dominance and synchronicity of different biochemical processes.
We analyzed variability in diel nitrate patterns at three locations in a lowland stream....
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