Articles | Volume 30, issue 2
https://doi.org/10.5194/hess-30-485-2026
© 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-30-485-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
30 Jan 2026
Research article |
| 30 Jan 2026
| 30 Jan 2026
Detecting the occurrence of preferential flow in soils with stable water isotopes
Jonas Pyschik
CORRESPONDING AUTHOR
Department of Hydrology, University of Freiburg, Freiburg, Germany
Invited contribution by Jonas Pyschik, recipient of the EGU Hydrological Sciences Outstanding Student Poster and PICO Award 2023.
Markus Weiler
Department of Hydrology, University of Freiburg, Freiburg, Germany
Related authors
No articles found.
Heinke Paulsen and Markus Weiler
EGUsphere, https://doi.org/10.5194/egusphere-2026-284, https://doi.org/10.5194/egusphere-2026-284, 2026
This preprint is open for discussion and under review for Hydrology and Earth System Sciences (HESS).
Short summary
Short summary
Using 12 Forest floor (FF) lysimeters at three beech‑dominated sites, we recorded 1,570 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.
Emanuel Thoenes, Theresa Blume, Markus Weiler, Bernhard Kohl, Luisa Hopp, and Stefan Achleitner
EGUsphere, https://doi.org/10.5194/egusphere-2025-5110, https://doi.org/10.5194/egusphere-2025-5110, 2025
Short summary
Short summary
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, with threshold behaviour observed at one site. 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.
Jasmin Tesch, Kathrin Kühnhammer, Delon Wagner, Andreas Christen, Carsten Dormann, Julian Frey, Rüdiger Grote, Teja Kattenborn, Markus Sulzer, Ulrike Wallrabe, Markus Weiler, Christiane Werner, Samaneh Baghbani, Julian Brzozon, Laura Maria Comella, Lea Dedden, Stefanie Dumberger, Yasmina Frey, Matthias Gassilloud, Timo Gerach, Anna Göritz, Simon Haberstroh, Johannes Klüppel, Luis Kremer, Jürgen Kreuzwieser, Hojin Lee, Joachim Maack, Julian Müller, Oswald Prucker, Sanam Kumari Rajak, Jürgen Rühe, Stefan J. Rupitsch, Helmer Schack-Kirchner, Christian Scharinger, Uttunga Shinde, Till Steinmann, Clara Stock, and Josef Strack
EGUsphere, https://doi.org/10.5194/egusphere-2025-4979, https://doi.org/10.5194/egusphere-2025-4979, 2025
This preprint is open for discussion and under review for Geoscientific Instrumentation, Methods and Data Systems (GI).
Short summary
Short summary
In the ECOSENSE forest, we developed a robust infrastructure for distributed forest sensing. Reliable power supply, stable network connection, and smart data collection systems enable the operation of hundreds of sensors under challenging conditions. By detailing the infrastructure design and implementation, we provide a transferable blueprint for building complex monitoring sites that support high-resolution, long-term ecosystem observations.
Sebastian Gnann, Bailey J. Anderson, and Markus Weiler
EGUsphere, https://doi.org/10.5194/egusphere-2025-4527, https://doi.org/10.5194/egusphere-2025-4527, 2025
Short summary
Short summary
The extent to which streamflow varies in response to variability in precipitation and potential evaporation is essential for understanding climate change impacts on water resources. This so-called streamflow sensitivity is often estimated directly from observational data, but the robustness of these estimates remains unclear. Through systematic examination of existing approaches, we highlight uncertainties inherent in all approaches, discuss their origins, and propose potential alternatives.
Hannes Leistert, Andreas Hänsler, Max Schmit, Andreas Steinbrich, and Markus Weiler
EGUsphere, https://doi.org/10.5194/egusphere-2025-4447, https://doi.org/10.5194/egusphere-2025-4447, 2025
Short summary
Short summary
The newly developed model AccRo (Accumulation-based Runoff and Pluvial Flood Estimation Tool) is a computationally efficient method to derive key parameters for estimating pluvial flood hazards. Here, we compare results of AccRo with the data of two hydrodynamic models for different cases. We find that AccRo is able to represent the simulations of the hydrodynamic models in high quality, but with much lower computational effort, making it a valuable tool for assessing pluvial flood hazards.
Hassane Moutahir, Markus Sulzer, Ralf Kiese, Andreas Christen, Markus Weiler, Lea Dedden, Julian Brzozon, Pia Labenski, Prajwal Khanal, Ladislav Šigut, and Rüdiger Grote
EGUsphere, https://doi.org/10.5194/egusphere-2025-4605, https://doi.org/10.5194/egusphere-2025-4605, 2025
Short summary
Short summary
Eddy covariance (EC) data are vital for studying carbon and water fluxes but often mask species-specific responses in mixed forests. At a Black Forest site with beech and Douglas fir, we combined EC data with ecosystem modeling to separate species contributions. Results show EC fluxes reflect species abundance within flux footprints, though responses vary seasonally. Accounting for these differences is key for gap-filling, accurate budgets, and understanding mixed forests’ climate resilience.
Theresa Blume, Peter Chifflard, Stefan Achleitner, Andreas Hartmann, Stefan Hergarten, Luisa Hopp, Bernhard Kohl, Florian Leese, Ilja van Meerveld, Christian Reinhardt-Imjela, and Markus Weiler
EGUsphere, https://doi.org/10.5194/egusphere-2025-4424, https://doi.org/10.5194/egusphere-2025-4424, 2025
Short summary
Short summary
Subsurface stormflow (SSF) is one of the least studied and therefore least understood runoff generation processes because detecting and quantifying SSF is extremely challenging. We present an ongoing concerted experimental effort to systematically investigate SSF across four catchments using a variety of methods covering different spatial scales. Centerpiece of this effort is the construction of 12 large trenches to capture and monitor SSF.
Lea Dedden and Markus Weiler
EGUsphere, https://doi.org/10.5194/egusphere-2025-4285, https://doi.org/10.5194/egusphere-2025-4285, 2025
Short summary
Short summary
Throughfall in forests varies in space and time creating distinct patterns. We developed a novel throughfall monitoring approach for continuous, automated measurement that features 60 self-built and cost effective throughfall samplers. Collected data show the potential of the approach to capture throughfall variability at small distances, among and within rainfall events and between different trees species.
Heinke Paulsen and Markus Weiler
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
Short summary
Short summary
This technical note describes the development of a weighing forest floor grid lysimeter. The device is needed to investigate the dynamics of the water balance components of the organic layer in forests, quantifying precipitation, drainage, evaporation, and storage. We designed a setup that can be easily rebuilt and that is cost-effective, which allows for customized applications. Performance metrics from laboratory results and initial field data are presented.
Markus Weiler, Julia Krumm, Ingo Haag, Hannes Leistert, Max Schmit, Andreas Steinbrich, and Andreas Hänsler
EGUsphere, https://doi.org/10.5194/egusphere-2025-1519, https://doi.org/10.5194/egusphere-2025-1519, 2025
Short summary
Short summary
Pluvial (flash) floods, caused by intense local rainfall, result in surface runoff and overland flow, making them different from fluvial floods. A new Pluvial Flood Index (PFI) combines precipitation, hydrological, and hydrodynamic processes to assess surface flooding hazards. The PFI, based on flood hazard areas, helps forecast flash floods and supports real-time warning systems, aiding municipal decision-making, preparedness, and planning.
Jonas Pyschik, Stefan Seeger, Barbara Herbstritt, and Markus Weiler
Hydrol. Earth Syst. Sci., 29, 525–534, https://doi.org/10.5194/hess-29-525-2025, https://doi.org/10.5194/hess-29-525-2025, 2025
Short summary
Short summary
We developed a device (named VapAuSa) that automates stable water isotope analysis. Stable water isotopes are a natural tracer that many researchers use to investigate water (re-)distribution processes in environmental systems. VapAuSa helps to analyse such environmental samples by automating a formerly tedious manual process, allowing for higher sample throughput. This enables larger sampling campaigns, as more samples can be processed before reaching their limited storage time.
Robin Schwemmle, Hannes Leistert, Andreas Steinbrich, and Markus Weiler
Geosci. Model Dev., 17, 5249–5262, https://doi.org/10.5194/gmd-17-5249-2024, https://doi.org/10.5194/gmd-17-5249-2024, 2024
Short summary
Short summary
The new process-based hydrological toolbox model, RoGeR (https://roger.readthedocs.io/), can be used to estimate the components of the hydrological cycle and the related travel times of pollutants through parts of the hydrological cycle. These estimations may contribute to effective water resources management. This paper presents the toolbox concept and provides a simple example of providing estimations to water resources management.
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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.
Jan Greiwe, Markus Weiler, and Jens Lange
Biogeosciences, 18, 4705–4715, https://doi.org/10.5194/bg-18-4705-2021, https://doi.org/10.5194/bg-18-4705-2021, 2021
Short summary
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.
Stefan Seeger and Markus Weiler
Biogeosciences, 18, 4603–4627, https://doi.org/10.5194/bg-18-4603-2021, https://doi.org/10.5194/bg-18-4603-2021, 2021
Short summary
Short summary
We developed a setup for fully automated in situ measurements of stable water isotopes in soil and the stems of fully grown trees. We used this setup in a 12-week field campaign to monitor the propagation of a labelling pulse from the soil up to a stem height of 8 m.
We could observe trees shifting their main water uptake depths multiple times, depending on water availability.
The gained knowledge about the temporal dynamics can help to improve water uptake models and future study designs.
Andreas Hänsler and Markus Weiler
Hydrol. Earth Syst. Sci. Discuss., https://doi.org/10.5194/hess-2021-366, https://doi.org/10.5194/hess-2021-366, 2021
Manuscript not accepted for further review
Short summary
Short summary
Spatially explicit quantification on design storms are essential for flood risk assessment. However this information can be only achieved from substantially long records of rainfall measurements, usually only available for a few stations. Hence, design storms estimates from these few stations are then spatially interpolated leading to a major source of uncertainty. Therefore we defined a methodology to extend spatially explicit weather radar data to be used for the estimation of design storms.
Anne Hartmann, Markus Weiler, Konrad Greinwald, and Theresa Blume
Hydrol. Earth Syst. Sci. Discuss., https://doi.org/10.5194/hess-2021-242, https://doi.org/10.5194/hess-2021-242, 2021
Manuscript not accepted for further review
Short summary
Short summary
Our field observation-based examination of flow path evolution, soil formation and vegetation succession across ten millennia on calcareous parent material shows how water flow paths and subsurface water storage are linked to the organization of evolving landscapes. We provide important but rare data and observations for a proper handling of hydrologic processes and their role within the feedback cycle of the hydro-pedo-geomorphological system.
Axel Schaffitel, Tobias Schuetz, and Markus Weiler
Geosci. Model Dev., 14, 2127–2142, https://doi.org/10.5194/gmd-14-2127-2021, https://doi.org/10.5194/gmd-14-2127-2021, 2021
Short summary
Short summary
This paper presents FluSM, an algorithm to derive the water balance from soil moisture and metrological measurements. This data-driven water balance framework uses soil moisture as an input and therefore is applicable for cases with unclear processes and lacking parameters. In a case study, we apply FluSM to derive the water balance of 15 different permeable pavements under field conditions. These findings are of special interest for urban hydrology.
Robin Schwemmle, Dominic Demand, and Markus Weiler
Hydrol. Earth Syst. Sci., 25, 2187–2198, https://doi.org/10.5194/hess-25-2187-2021, https://doi.org/10.5194/hess-25-2187-2021, 2021
Short summary
Short summary
A better understanding of the reasons why model performance is unsatisfying represents a crucial part for meaningful model evaluation. We propose the novel diagnostic efficiency (DE) measure and diagnostic polar plots. The proposed evaluation approach provides a diagnostic tool for model developers and model users and facilitates interpretation of model performance.
Michael Rinderer, Jaane Krüger, Friederike Lang, Heike Puhlmann, and Markus Weiler
Biogeosciences, 18, 1009–1027, https://doi.org/10.5194/bg-18-1009-2021, https://doi.org/10.5194/bg-18-1009-2021, 2021
Short summary
Short summary
We quantified the lateral and vertical subsurface flow (SSF) and P concentrations of three beech forest plots with contrasting soil properties during sprinkling experiments. Vertical SSF was 2 orders of magnitude larger than lateral SSF, and both consisted mainly of pre-event water. P concentrations in SSF were high during the first 1 to 2 h (nutrient flushing) but nearly constant thereafter. This suggests that P in the soil solution was replenished fast by mineral or organic sources.
Merle Koelbing, Tobias Schuetz, and Markus Weiler
Hydrol. Earth Syst. Sci. Discuss., https://doi.org/10.5194/hess-2021-24, https://doi.org/10.5194/hess-2021-24, 2021
Revised manuscript not accepted
Short summary
Short summary
Based on a unique and comprehensive data set of urban micro-meteorological variables, which were observed with a mobile climate station, we developed a new method to transfer mesoscale reference potential evapotranspiration to the urban microscale in street canyons. Our findings can be transferred easily to existing urban hydrologic models to improve modelling results with a more precise estimate of potential evapotranspiration on street level.
Cited articles
Alaoui, A. and Helbling, A.: Evaluation of Soil Compaction Using Hydrodynamic Water Content Variation: Comparison between Compacted and Non-Compacted Soil, Geoderma, 134, 97–108, https://doi.org/10.1016/j.geoderma.2005.08.016, 2006. a, b
Anderson, A. E., Weiler, M., Alila, Y., and Hudson, R. O.: Dye staining and excavation of a lateral preferential flow network, Hydrol. Earth Syst. Sci., 13, 935–944, https://doi.org/10.5194/hess-13-935-2009, 2009a. a
Angermann, L., Jackisch, C., Allroggen, N., Sprenger, M., Zehe, E., Tronicke, J., Weiler, M., and Blume, T.: Form and function in hillslope hydrology: characterization of subsurface flow based on response observations, Hydrol. Earth Syst. Sci., 21, 3727–3748, https://doi.org/10.5194/hess-21-3727-2017, 2017. a, b, c, d, e, f, g, h, i, j
Araguás-Araguás, L., Froehlich, K., and Rozanski, K.: Deuterium and Oxygen-18 Isotope Composition of Precipitation and Atmospheric Moisture, Hydrol. Process., 14, 1341–1355, https://doi.org/10.1002/1099-1085(20000615)14:8<1341::AID-HYP983>3.0.CO;2-Z, 2000. a, b
Bachmair, S. and Weiler, M.: Hillslope characteristics as controls of subsurface flow variability, Hydrol. Earth Syst. Sci., 16, 3699–3715, https://doi.org/10.5194/hess-16-3699-2012, 2012. a, b
Bachmair, S. and Weiler, M.: Interactions and Connectivity between Runoff Generation Processes of Different Spatial Scales: Interactions runoff generation processes of different spatial scales, Hydrol. Process., 28, 1916–1930, https://doi.org/10.1002/hyp.9705, 2014. a
Badorreck, A., Gerke, H. H., and Hüttl, R. F.: Effects of Ground-Dwelling Beetle Burrows on Infiltration Patterns and Pore Structure of Initial Soil Surfaces, Vadose Zone J., 11, https://doi.org/10.2136/vzj2011.0109, 2012. a
Beven, K.: How to Make Advances in Hydrological Modelling, Hydrol. Res., 50, 1481–1494, https://doi.org/10.2166/nh.2019.134, 2019. a
Beven, K. and Germann, P.: Macropores and Water Flow in Soils, Water Resour. Res., 18, 1311–1325, https://doi.org/10.1029/WR018i005p01311, 1982. a, b, c
Beven, K. and Germann, P.: Macropores and Water Flow in Soils Revisited: REVIEW, Water Resour. Res., 49, 3071–3092, https://doi.org/10.1002/wrcr.20156, 2013. a, b, c, d
Blume, T., Zehe, E., and Bronstert, A.: Use of soil moisture dynamics and patterns at different spatio-temporal scales for the investigation of subsurface flow processes, Hydrol. Earth Syst. Sci., 13, 1215–1233, https://doi.org/10.5194/hess-13-1215-2009, 2009. a
Bouma, J.: Comment on “Micro-, Meso-, and Macroporosity of Soil”, Soil Sci. Soc. Am. J., 45, 1244–1245, https://doi.org/10.2136/sssaj1981.03615995004500060050x, 1981. a
Bouma, J. and Dekker, L. W.: A Case Study on Infiltration into Dry Clay Soil I. Morphological Observations, Geoderma, 20, 27–40, https://doi.org/10.1016/0016-7061(78)90047-2, 1978. a, b
Bouma, J., Jongerius, A., Boersma, O., Jager, A., and Schoonderbeek, D.: The Function of Different Types of Macropores During Saturated Flow through Four Swelling Soil Horizons, Soil Sci. Soc. Am. J., 41, 945–950, https://doi.org/10.2136/sssaj1977.03615995004100050028x, 1977. a, b
Cheng, L., Liu, W., Li, Z., and Chen, J.: Study of Soil Water Movement and Groundwater Recharge for the Loess Tableland Using Environmental Tracers, T. ASABE, 23–30, https://doi.org/10.13031/trans.57.10017, 2014. a, b
Cheng, Y., Ogden, F. L., Zhu, J., and Bretfeld, M.: Land Use-Dependent Preferential Flow Paths Affect Hydrological Response of Steep Tropical Lowland Catchments With Saprolitic Soils, Water Resour. Res., 54, 5551–5566, https://doi.org/10.1029/2017WR021875, 2018. a, b
Chifflard, P., Didszun, J., and Zepp, H.: Skalenübergreifende Prozess-Studien zur Abflussbildung in Gebieten mit periglazialen Deckschichten (Sauerland, Deutschland), Grundwasser, 13, 27–41, https://doi.org/10.1007/s00767-007-0058-1, 2008. a
Craig, H.: Isotopic Variations in Meteoric Waters, Science, 133, 1702–1703, https://doi.org/10.1126/science.133.3465.1702, 1961. a
Dansgaard, W.: Stable Isotopes in Precipitation, Tellus, 16, 436–468, https://doi.org/10.3402/tellusa.v16i4.8993, 1964. a
David, K., Timms, W., Hughes, C. E., Crawford, J., and McGeeney, D.: Application of the pore water stable isotope method and hydrogeological approaches to characterise a wetland system, Hydrol. Earth Syst. Sci., 22, 6023–6041, https://doi.org/10.5194/hess-22-6023-2018, 2018. a, b
Demand, D., Blume, T., and Weiler, M.: Spatio-temporal relevance and controls of preferential flow at the landscape scale, Hydrol. Earth Syst. Sci., 23, 4869–4889, https://doi.org/10.5194/hess-23-4869-2019, 2019a. a, b, c
Demand, D., Selker, J. S., and Weiler, M.: Influences of Macropores on Infiltration into Seasonally Frozen Soil, Vadose Zone J., 18, 180147, https://doi.org/10.2136/vzj2018.08.0147, 2019b. a
Eguchi, S. and Hasegawa, S.: Determination and Characterization of Preferential Water Flow in Unsaturated Subsoil of Andisol, Soil Sci. Soc. Am. J., 72, 320–330, https://doi.org/10.2136/sssaj2007.0042, 2008. a
European Space Agency: Copernicus Global Digital Elevation Model GLO-30, OpenTopography, https://doi.org/10.5069/G9028PQB, 2024. a
Gehrels, J. C., Peeters, J. E. M., De Vries, J. J., and Dekkers, M.: The Mechanism of Soil Water Movement as Inferred from 18O Stable Isotope Studies, Hydrolog. Sci. J., 43, 579–594, https://doi.org/10.1080/02626669809492154, 1998. a, b, c
Gimbel, K. F., Puhlmann, H., and Weiler, M.: Does drought alter hydrological functions in forest soils?, Hydrol. Earth Syst. Sci., 20, 1301–1317, https://doi.org/10.5194/hess-20-1301-2016, 2016. a
Govan, E. and Parnell, A.: Simmr: A Stable Isotope Mixing Model, https://cran.r-project.org/web/packages/simmr/index.html (last access: 28 January 2026) 2023. a
Gralher, B., Herbstritt, B., and Weiler, M.: Technical note: Unresolved aspects of the direct vapor equilibration method for stable isotope analysis (δ18O, δ2H) of matrix-bound water: unifying protocols through empirical and mathematical scrutiny, Hydrol. Earth Syst. Sci., 25, 5219–5235, https://doi.org/10.5194/hess-25-5219-2021, 2021. a, b, c
Guan, N., Cheng, J., and Shi, X.: Preferential Flow and Preferential Path Characteristics of the Typical Forests in the Karst Region of Southwest China, Forests, 14, 1248, https://doi.org/10.3390/f14061248, 2023. a
Guo, L., Chen, J., and Lin, H.: Subsurface Lateral Preferential Flow Network Revealed by Time-Lapse Ground-Penetrating Radar in a Hillslope, Water Resour. Res., 50, 9127–9147, https://doi.org/10.1002/2013WR014603, 2014. a, b, c
Heilig, A., Steenhuis, T. S., Walter, M. T., and Herbert, S. J.: Funneled Flow Mechanisms in Layered Soil: Field Investigations, J. Hydrol., 279, 210–223, https://doi.org/10.1016/S0022-1694(03)00179-3, 2003. a, b
Heller, K. and Kleber, A.: Hillslope Runoff Generation Influenced by Layered Subsurface in a Headwater Catchment in Ore Mountains, Germany, Environmental Earth Sciences, 75, 943, https://doi.org/10.1007/s12665-016-5750-y, 2016. a
Holden, J., Burt, T. P., and Vilas, M.: Application of Ground-Penetrating Radar to the Identification of Subsurface Piping in Blanket Peat, Earth Surf. Proc. Land., 27, 235–249, https://doi.org/10.1002/esp.316, 2002. a
Jones, J. A. A.: Soil Piping and Catchment Response, Hydrol. Process., 24, 1548–1566, https://doi.org/10.1002/hyp.7634, 2010. a, b
Katuwal, S., Moldrup, P., Lamandé, M., Tuller, M., and de Jonge, L. W.: Effects of CT Number Derived Matrix Density on Preferential Flow and Transport in a Macroporous Agricultural Soil, Vadose Zone J., 14, vzj2015.01.0002, https://doi.org/10.2136/vzj2015.01.0002, 2015. a
Kelln, C., Barbour, L., and Qualizza, C.: Preferential Flow in a Reclamation Cover: Hydrological and Geochemical Response, Journal of Geotechnical and Geoenvironmental Engineering, 133, 1277–1289, https://doi.org/10.1061/(ASCE)1090-0241(2007)133:10(1277), 2007. a, b, c
Khan, M. R., Koneshloo, M., Knappett, P. S. K., Ahmed, K. M., Bostick, B. C., Mailloux, B. J., Mozumder, R. H., Zahid, A., Harvey, C. F., van Geen, A., and Michael, H. A.: Megacity Pumping and Preferential Flow Threaten Groundwater Quality, Nat. Commun., 7, 12833, https://doi.org/10.1038/ncomms12833, 2016. a
Klaus, J., Zehe, E., Elsner, M., Külls, C., and McDonnell, J. J.: Macropore flow of old water revisited: experimental insights from a tile-drained hillslope, Hydrol. Earth Syst. Sci., 17, 103–118, https://doi.org/10.5194/hess-17-103-2013, 2013. a
Kodešová, R., Němeček, K., Kodeš, V., and Žigová, A.: Using Dye Tracer for Visualization of Preferential Flow at Macro- and Microscales, Vadose Zone J., 11, vzj2011.0088, https://doi.org/10.2136/vzj2011.0088, 2012. a, b, c
Kotikian, M., Parsekian, A. D., Paige, G., and Carey, A.: Observing Heterogeneous Unsaturated Flow at the Hillslope Scale Using Time-Lapse Electrical Resistivity Tomography, Vadose Zone J., 18, 1–16, https://doi.org/10.2136/vzj2018.07.0138, 2019. a
Kuhn, M.: Building Predictive Models in R Using the Caret Package, Journal of Statistical Software, 28, https://doi.org/10.18637/jss.v028.i05, 2008. a
Kung, K.-J. S.: Preferential Flow in a Sandy Vadose Zone: 1. Field Observation, Geoderma, 46, 51–58, https://doi.org/10.1016/0016-7061(90)90006-U, 1990. a, b
Leaney, F. W., Smettem, K. R. J., and Chittleborough, D. J.: Estimating the Contribution of Preferential Flow to Subsurface Runoff from a Hillslope Using Deuterium and Chloride, J. Hydrol., 147, 83–103, https://doi.org/10.1016/0022-1694(93)90076-L, 1993. a, b, c
Leibundgut, C., Maloszewski, P., and Külls, C.: Tracers in Hydrology, Wiley, 1 edn., https://doi.org/10.1002/9780470747148, 2009. a, b, c
Leslie, I. and Heinse, R.: Characterizing Soil–Pipe Networks with Pseudo-Three-Dimensional Resistivity Tomography on Forested Hillslopes with Restrictive Horizons, Vadose Zone J., 12, vzj2012.0200, https://doi.org/10.2136/vzj2012.0200, 2013. a
Liu, Z., Bowen, G. J., and Welker, J. M.: Atmospheric Circulation Is Reflected in Precipitation Isotope Gradients over the Conterminous United States, J. Geophys. Res.-Atmos., 115, https://doi.org/10.1029/2010JD014175, 2010. a
Lu, D., Wang, H., Geng, N., Xia, Y., Xu, C., and Hua, E.: Imaging and Characterization of the Preferential Flow Process in Agricultural Land by Using Electrical Resistivity Tomography and Dual-Porosity Model, Ecol. Indic., 134, 108498, https://doi.org/10.1016/j.ecolind.2021.108498, 2022. a
Luo, L., Lin, H., and Halleck, P.: Quantifying Soil Structure and Preferential Flow in Intact Soil Using X-ray Computed Tomography, Soil Sci. Soc. Am. J., 72, 1058–1069, https://doi.org/10.2136/sssaj2007.0179, 2008. a, b
Małoszewski, P., Maciejewski, S., Stumpp, C., Stichler, W., Trimborn, P., and Klotz, D.: Modelling of Water Flow through Typical Bavarian Soils: 2. Environmental Deuterium Transport, Hydrolog. Sci. J., 51, 298–313, https://doi.org/10.1623/hysj.51.2.298, 2006. a, b
Mathieu, R. and Bariac, T.: An Isotopic Study (2H and 18O) of Water Movements in Clayey Soils Under a Semiarid Climate, Water Resour. Res., 32, 779–789, https://doi.org/10.1029/96WR00074, 1996. a, b
Mueller, M. H., Alaoui, A., Kuells, C., Leistert, H., Meusburger, K., Stumpp, C., Weiler, M., and Alewell, C.: Tracking Water Pathways in Steep Hillslopes by δ18O Depth Profiles of Soil Water, J. Hydrol., 519, 340–352, https://doi.org/10.1016/j.jhydrol.2014.07.031, 2014. a, b
Orlowski, N., Kraft, P., Pferdmenges, J., and Breuer, L.: Exploring water cycle dynamics by sampling multiple stable water isotope pools in a developed landscape in Germany, Hydrol. Earth Syst. Sci., 20, 3873–3894, https://doi.org/10.5194/hess-20-3873-2016, 2016. a
Paradelo, M., Katuwal, S., Moldrup, P., Norgaard, T., Herath, L., and de Jonge, L.: X-Ray CT-Derived Soil Characteristics Explain Varying Air, Water, and Solute Transport Properties across a Loamy Field, Vadose Zone J., 15, https://doi.org/10.2136/vzj2015.07.0104, 2016. a, b
Peralta-Tapia, A., Sponseller, R. A., Tetzlaff, D., Soulsby, C., and Laudon, H.: Connecting Precipitation Inputs and Soil Flow Pathways to Stream Water in Contrasting Boreal Catchments, Hydrol. Process., 29, 3546–3555, https://doi.org/10.1002/hyp.10300, 2015. a
Pinos, J., Flury, M., Latron, J., and Llorens, P.: Routing stemflow water through the soil via preferential flow: a dual-labelling approach with artificial tracers, Hydrol. Earth Syst. Sci., 27, 2865–2881, https://doi.org/10.5194/hess-27-2865-2023, 2023. a
Pyschik, J., Seeger, S., Herbstritt, B., and Weiler, M.: Technical note: A fast and reproducible autosampler for direct vapor equilibration isotope measurements, Hydrol. Earth Syst. Sci., 29, 525–534, https://doi.org/10.5194/hess-29-525-2025, 2025a. a
Pyschik, J., Thoenes, E., Achleitner, S., Kohl, B., and Weiler, M.: Tracing Subsurface Stormflow: Insights into Preferential Flow and Pre-Event Water Contributions from Controlled Sprinkling Experiments, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-10457, https://doi.org/10.5194/egusphere-egu25-10457, 2025b. a
R Core Team: R: A Language and Environment for Statistical Computing, Vienna, Austria, https://www.r-project.org/ (last access: 28 January 2026), 2024. a
Rozanski, K., Araguás-Araguás, L., and Gonfiantini, R.: Isotopic Patterns in Modern Global Precipitation, in: Geophysical Monograph Series, edited by: Swart, P. K., Lohmann, K. C., Mckenzie, J., and Savin, S., American Geophysical Union, Washington, DC, 1–36, https://doi.org/10.1029/GM078p0001, 2013. a
Sammartino, S., Lissy, A.-S., Bogner, C., Bogaert, R., Capowiez, Y., Ruy, S., and Cornu, S.: Identifying the Functional Macropore Network Related to Preferential Flow in Structured Soils, Vadose Zone J., 14, https://doi.org/10.2136/vzj2015.05.0070, 2015. a
Scaini, A., Audebert, M., Hissler, C., Fenicia, F., Gourdol, L., Pfister, L., and Beven, K. J.: Velocity and Celerity Dynamics at Plot Scale Inferred from Artificial Tracing Experiments and Time-Lapse ERT, J. Hydrol., 546, 28–43, https://doi.org/10.1016/j.jhydrol.2016.12.035, 2017. a, b
Selker, J., Leclerq, P., Parlange, J.-Y., and Steenhuis, T.: Fingered Flow in Two Dimensions: 1. Measurement of Matric Potential, Water Resour. Res., 28, 2513–2521, https://doi.org/10.1029/92WR00963, 1992a. a
Selker, J., Parlange, J.-Y., and Steenhuis, T.: Fingered Flow in Two Dimensions: 2. Predicting Finger Moisture Profile, Water Resour. Res., 28, 2523–2528, https://doi.org/10.1029/92WR00962, 1992b. a
Sprenger, M., Volkmann, T. H. M., Blume, T., and Weiler, M.: Estimating flow and transport parameters in the unsaturated zone with pore water stable isotopes, Hydrol. Earth Syst. Sci., 19, 2617–2635, https://doi.org/10.5194/hess-19-2617-2015, 2015. a
Sprenger, M., Erhardt, M., Riedel, M., and Weiler, M.: Historical Tracking of Nitrate in Contrasting Vineyards Using Water Isotopes and Nitrate Depth Profiles, Agr. Ecosyst. Environ., 222, 185–192, https://doi.org/10.1016/j.agee.2016.02.014, 2016a. a, b
Sprenger, M., Leistert, H., Gimbel, K., and Weiler, M.: Illuminating Hydrological Processes at the Soil-Vegetation-Atmosphere Interface with Water Stable Isotopes: Review of Water Stable Isotopes, Rev. Geophys., 54, 674–704, https://doi.org/10.1002/2015RG000515, 2016b. a
Stumpp, C. and Hendry, M. J.: Spatial and Temporal Dynamics of Water Flow and Solute Transport in a Heterogeneous Glacial till: The Application of High-Resolution Profiles of δ18O and δ2H in Pore Waters, J. Hydrol., 438–439, 203–214, https://doi.org/10.1016/j.jhydrol.2012.03.024, 2012. a
Täumer, K., Stoffregen, H., and Wessolek, G.: Seasonal Dynamics of Preferential Flow in a Water Repellent Soil, Vadose Zone J., 5, https://doi.org/10.2136/vzj2005.0031, 2006. a
Thomas, E. M., Lin, H., Duffy, C. J., Sullivan, P. L., Holmes, G. H., Brantley, S. L., and Jin, L.: Spatiotemporal Patterns of Water Stable Isotope Compositions at the Shale Hills Critical Zone Observatory: Linkages to Subsurface Hydrologic Processes, Vadose Zone J., 12, vzj2013.01.0029, https://doi.org/10.2136/vzj2013.01.0029, 2013. a, b, c, d, e
Tromp-van Meerveld, H. J. and McDonnell, J. J.: Threshold Relations in Subsurface Stormflow: 1. A 147-Storm Analysis of the Panola Hillslope: Subsurface Flow Relations, 1, Water Resour. Res., 42, https://doi.org/10.1029/2004WR003778, 2006. a
Uchida, T., Asano, Y., Onda, Y., and Miyata, S.: Are Headwaters Just the Sum of Hillslopes?, Hydrol. Process., 19, 3251–3261, https://doi.org/10.1002/hyp.6004, 2005. a, b
Wassenaar, L., Hendry, M., Chostner, V., and Lis, G.: High Resolution Pore Water δ2H and δ18O Measurements by H2O(Liquid)–H2O(Vapor) Equilibration Laser Spectroscopy, Environ. Sci. Technol., 42, 9262–9267, https://doi.org/10.1021/es802065s, 2008. a
Watson, K. W. and Luxmoore, R. J.: Estimating Macroporosity in a Forest Watershed by Use of a Tension Infiltrometer, Soil Sci. Soc. Am. J., 50, 578–582, https://doi.org/10.2136/sssaj1986.03615995005000030007x, 1986. a
Wessolek, G., Stoffregen, H., and Täumer, K.: Persistency of Flow Patterns in a Water Repellent Sandy Soil – Conclusions of TDR Readings and a Time-Delayed Double Tracer Experiment, J. Hydrol., 375, 524–535, https://doi.org/10.1016/j.jhydrol.2009.07.003, 2009. a, b
Wilson, G. V., Nieber, J. L., Sidle, R. C., and Fox, G. A.: Internal Erosion during Soil Pipeflow: State of the Science for Experimental and Numerical Analysis, T. ASABE, 56, 465–478, https://doi.org/10.13031/2013.42667, 2013. a
Wilson, G. V., Rigby, J. R., Ursic, M., and Dabney, S. M.: Soil Pipe Flow Tracer Experiments: 1. Connectivity and Transport Characteristics, Hydrol. Process., 30, 1265–1279, https://doi.org/10.1002/hyp.10713, 2016. a, b
Zanaga, D., Van De Kerchove, R., De Keersmaecker, W., Souverijns, N., Brockmann, C., Quast, R., Wevers, J., Grosu, A., Paccini, A., Vergnaud, S., Cartus, O., Santoro, M., Fritz, S., Georgieva, I., Lesiv, M., Carter, S., Herold, M., Li, L., Tsendbazar, N.-E., Ramoino, F., and Arino, O.: ESA WorldCover 10 m 2020 V100, https://doi.org/10.5281/ZENODO.5571936, 2021. a
Zhao, P., Tang, X., Zhao, P., Wang, C., and Tang, J.: Identifying the Water Source for Subsurface Flow with Deuterium and Oxygen-18 Isotopes of Soil Water Collected from Tension Lysimeters and Cores, J. Hydrol., 503, 1–10, https://doi.org/10.1016/j.jhydrol.2013.08.033, 2013. a
Short summary
This study introduces a new method of detecting how water moves quickly through certain paths in soil, bypassing the usual, slower flow. By analysing natural water markers in soil samples taken at different depths, we identified unusual flow patterns. Our method is simple and non-invasive, and can be used to cover large areas. This helps us to better understand how water travels through the ground, which is important for managing water resources and protecting the environment.
This study introduces a new method of detecting how water moves quickly through certain paths in...
