Articles | Volume 26, issue 8
https://doi.org/10.5194/hess-26-2073-2022
© Author(s) 2022. 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-26-2073-2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
27 Apr 2022
Research article |
| 27 Apr 2022
| 27 Apr 2022
Xylem water in riparian willow trees (Salix alba) reveals shallow sources of root water uptake by in situ monitoring of stable water isotopes
Jessica Landgraf
CORRESPONDING AUTHOR
Department of Ecohydrology and Biogeochemistry, Leibniz Institute of Freshwater Ecology and Inland Fisheries, Müggelseedamm 310, 12587 Berlin, Germany
Department of Geography, Humboldt-Universität zu Berlin, Rudower Chaussee 16, 12489 Berlin, Germany
Dörthe Tetzlaff
Department of Ecohydrology and Biogeochemistry, Leibniz Institute of Freshwater Ecology and Inland Fisheries, Müggelseedamm 310, 12587 Berlin, Germany
Department of Geography, Humboldt-Universität zu Berlin, Rudower Chaussee 16, 12489 Berlin, Germany
Northern Rivers Institute, University of Aberdeen, St. Mary's Building, Kings College, Old Aberdeen, AB24 3UE, UK
Maren Dubbert
Department of Ecohydrology and Biogeochemistry, Leibniz Institute of Freshwater Ecology and Inland Fisheries, Müggelseedamm 310, 12587 Berlin, Germany
Landscape Functioning, Leibniz Centre for Agricultural Landscape Research, Eberswalder Straße 84, 15374 Müncheberg, Germany
David Dubbert
Department of Ecohydrology and Biogeochemistry, Leibniz Institute of Freshwater Ecology and Inland Fisheries, Müggelseedamm 310, 12587 Berlin, Germany
Aaron Smith
Department of Ecohydrology and Biogeochemistry, Leibniz Institute of Freshwater Ecology and Inland Fisheries, Müggelseedamm 310, 12587 Berlin, Germany
Chris Soulsby
Northern Rivers Institute, University of Aberdeen, St. Mary's Building, Kings College, Old Aberdeen, AB24 3UE, UK
Related authors
Aaron Smith, Doerthe Tetzlaff, Jessica Landgraf, Maren Dubbert, and Chris Soulsby
Biogeosciences, 19, 2465–2485, https://doi.org/10.5194/bg-19-2465-2022, https://doi.org/10.5194/bg-19-2465-2022, 2022
Short summary
Short summary
This research utilizes high-spatiotemporal-resolution soil and vegetation measurements, including water stable isotopes, within an ecohydrological model to partition water flux dynamics and identify flow paths and durations. Results showed high vegetation water use and high spatiotemporal dynamics of vegetation water source and vegetation isotopes. The evaluation of these dynamics further revealed relatively fast flow paths through both shallow soil and vegetation.
Songjun Wu, Doerthe Tetzlaff, Yi Zheng, and Chris Soulsby
EGUsphere, https://doi.org/10.5194/egusphere-2025-3941, https://doi.org/10.5194/egusphere-2025-3941, 2025
This preprint is open for discussion and under review for Geoscientific Model Development (GMD).
Short summary
Short summary
We developed EcoTWIN v1.0, a new fully distributed tracer-aided ecohydrological model that tracks water, isotopes, and nutrients fluxes. The model was successfully tested in 17 large European catchments across diverse geological and climatic backgrounds. As a tracer-aided model, EcoTWIN not only captures flow paths but also estimates water ages/travel times, thus bridging hydrology with water quality. This opens new possibilities for understanding the synergy between water and nitrogen cycles.
John D. Marshall, Maren Dubbert, Teresa E. Gimeno, Ruth-Kristina Magh, Kathrin Kühnhammer, David Dubbert, Paul Koeniger, Matthias Cuntz, and Matthias Beyer
EGUsphere, https://doi.org/10.5194/egusphere-2025-3025, https://doi.org/10.5194/egusphere-2025-3025, 2025
This preprint is open for discussion and under review for Hydrology and Earth System Sciences (HESS).
Short summary
Short summary
Water transport in forest soils occurs partly through roots, both vertically and horizontally. We added a stable isotope label to a small forest plot and monitored its passage vertically into the soil and horizontally into stems of surrounding trees. The labelled water was detected in trees up to 6.7 m away, but was mostly taken up by one tree adjacent to the plot. These results affect how we think about summing over individual trees to describe the water economy of a whole forest.
Maria Magdalena Warter, Dörthe Tetzlaff, Chris Soulsby, Tobias Goldhammer, Daniel Gebler, Kati Vierikko, and Michael T. Monaghan
Hydrol. Earth Syst. Sci., 29, 2707–2725, https://doi.org/10.5194/hess-29-2707-2025, https://doi.org/10.5194/hess-29-2707-2025, 2025
Short summary
Short summary
There is a lack of understanding of how urban aquatic nature-based solutions (aquaNBSs) affect ecohydrology and how they in turn are affected by urbanization and climate change. We use a multi-tracer approach of stable water isotopes, hydrochemistry, and microbial and macrophyte diversity to disentangle the effects of hydroclimate and urbanization. The results show potential limitations of aquaNBSs regarding water quality and biodiversity in response to hydroclimate and urban water sources.
Cong Jiang, Doerthe Tetzlaff, Songjun Wu, Christian Birkel, Hjalmar Laudon, and Chris Soulsby
EGUsphere, https://doi.org/10.5194/egusphere-2025-2533, https://doi.org/10.5194/egusphere-2025-2533, 2025
This preprint is open for discussion and under review for Hydrology and Earth System Sciences (HESS).
Short summary
Short summary
We used a modelling approach supported by stable water isotopes to explore how forest management – such as conifer, broadleaf, and mixed tree–crop systems – affects water distribution and drought resilience in a drought-sensitive region of Germany. By representing forest type, density, and rooting depth, the model helps quantify and show how land use choices affect water availability and supports better land and water management decisions.
Adrian Dahlmann, John D. Marshall, David Dubbert, Mathias Hoffmann, and Maren Dubbert
Atmos. Meas. Tech., 18, 2607–2618, https://doi.org/10.5194/amt-18-2607-2025, https://doi.org/10.5194/amt-18-2607-2025, 2025
Short summary
Short summary
Water-stable isotopes are commonly used in hydrological and ecological research. Until now, measurements have been obtained either destructively or directly in the field. Here, we present a novel, affordable, and easy-to-use approach to measure the stable isotope signatures of soil water. Our gas bag approach demonstrates a high accuracy and extends usability by allowing water vapor samples to be collected and stored in the field without the need for an instrument or a permanent power supply.
Hanwu Zheng, Doerthe Tetzlaff, Christian Birkel, Songjun Wu, Tobias Sauter, and Chris Soulsby
EGUsphere, https://doi.org/10.5194/egusphere-2025-2166, https://doi.org/10.5194/egusphere-2025-2166, 2025
This preprint is open for discussion and under review for Hydrology and Earth System Sciences (HESS).
Short summary
Short summary
Ecohydrological processes in heavily managed catchments are often incorrectly represented in models. We applied a tracer-aided model STARR in an ET-dominated region (the Middle Spree, NE Germany) with major management impacts. Water isotopes were useful in identifying runoff contributions and partitioning ET even at sparse resolution. Trade-offs between discharge- and isotope-based calibrations could be partially mitigated by integrating more process-based conceptualizations into the model.
Ann-Marie Ring, Dörthe Tetzlaff, Christian Birkel, and Chris Soulsby
EGUsphere, https://doi.org/10.5194/egusphere-2025-1444, https://doi.org/10.5194/egusphere-2025-1444, 2025
Short summary
Short summary
During summer drought, a clear sub-daily cycling of atmospheric water vapour isotopes (δv) and plant xylem water isotopes (δxyl) was observed. δv daytime depletion was driven by evaporation and local atmospheric factors (entrainment). δxyl daytime enrichment was consistent with limited sap flow and stomatal regulation of transpiration. Water limitations during drought in urban trees are visible in δxyl and ecohydrological data. This sub-daily dataset can help constrain ecohydrological models.
Wael Al Hamwi, Maren Dubbert, Jörg Schaller, Matthias Lück, Marten Schmidt, and Mathias Hoffmann
Biogeosciences, 21, 5639–5651, https://doi.org/10.5194/bg-21-5639-2024, https://doi.org/10.5194/bg-21-5639-2024, 2024
Short summary
Short summary
We present a fully automatic, low-cost soil–plant enclosure system to monitor CO2 and evapotranspiration fluxes within greenhouse experiments. It operates in two modes: independent, using low-cost sensors, and dependent, where multiple chambers connect to a single gas analyzer via a low-cost multiplexer. This system provides precise, accurate measurements and high temporal resolution, enabling comprehensive monitoring of plant–soil responses to various treatments and conditions.
Maria Magdalena Warter, Dörthe Tetzlaff, Christian Marx, and Chris Soulsby
Nat. Hazards Earth Syst. Sci., 24, 3907–3924, https://doi.org/10.5194/nhess-24-3907-2024, https://doi.org/10.5194/nhess-24-3907-2024, 2024
Short summary
Short summary
Streams are increasingly impacted by droughts and floods. Still, the amount of water needed for sustainable flows remains unclear and contested. A comparison of two streams in the Berlin–Brandenburg region of northeast Germany, using stable water isotopes, shows strong groundwater dependence with seasonal rainfall contributing to high/low flows. Understanding streamflow variability can help us assess the impacts of climate change on future water resource management.
Marco M. Lehmann, Josie Geris, Ilja van Meerveld, Daniele Penna, Youri Rothfuss, Matteo Verdone, Pertti Ala-Aho, Matyas Arvai, Alise Babre, Philippe Balandier, Fabian Bernhard, Lukrecija Butorac, Simon Damien Carrière, Natalie C. Ceperley, Zuosinan Chen, Alicia Correa, Haoyu Diao, David Dubbert, Maren Dubbert, Fabio Ercoli, Marius G. Floriancic, Teresa E. Gimeno, Damien Gounelle, Frank Hagedorn, Christophe Hissler, Frédéric Huneau, Alberto Iraheta, Tamara Jakovljević, Nerantzis Kazakis, Zoltan Kern, Karl Knaebel, Johannes Kobler, Jiří Kocum, Charlotte Koeber, Gerbrand Koren, Angelika Kübert, Dawid Kupka, Samuel Le Gall, Aleksi Lehtonen, Thomas Leydier, Philippe Malagoli, Francesca Sofia Manca di Villahermosa, Chiara Marchina, Núria Martínez-Carreras, Nicolas Martin-StPaul, Hannu Marttila, Aline Meyer Oliveira, Gaël Monvoisin, Natalie Orlowski, Kadi Palmik-Das, Aurel Persoiu, Andrei Popa, Egor Prikaziuk, Cécile Quantin, Katja T. Rinne-Garmston, Clara Rohde, Martin Sanda, Matthias Saurer, Daniel Schulz, Michael Paul Stockinger, Christine Stumpp, Jean-Stéphane Venisse, Lukas Vlcek, Stylianos Voudouris, Björn Weeser, Mark E. Wilkinson, Giulia Zuecco, and Katrin Meusburger
Earth Syst. Sci. Data Discuss., https://doi.org/10.5194/essd-2024-409, https://doi.org/10.5194/essd-2024-409, 2024
Revised manuscript under review for ESSD
Short summary
Short summary
This study describes a unique large-scale isotope dataset to study water dynamics in European forests. Researchers collected data from 40 beech and spruce forest sites in spring and summer 2023, using a standardized method to ensure consistency. The results show that water sources for trees change between seasons and vary by tree species. This large dataset offers valuable information for understanding plant water use, improving ecohydrological models, and mapping water cycles across Europe.
Salim Goudarzi, Chris Soulsby, Jo Smith, Jamie Lee Stevenson, Alessandro Gimona, Scot Ramsay, Alison Hester, Iris Aalto, and Josie Geris
EGUsphere, https://doi.org/10.5194/egusphere-2024-2258, https://doi.org/10.5194/egusphere-2024-2258, 2024
Preprint archived
Short summary
Short summary
Planting trees on farmlands is now considered as one of the potential solutions to climate change. Trees can suck CO2 out of our atmosphere and store it in their trunks and in the soil beneath them. They can promote biodiversity, protect against soil erosion and drought. They can even help reduce flood risk for downstream communities. But we need models that can tell us the likely impact of trees at different locations and scales. Our study provides such a model.
Reena Macagga, Michael Asante, Geoffroy Sossa, Danica Antonijević, Maren Dubbert, and Mathias Hoffmann
Atmos. Meas. Tech., 17, 1317–1332, https://doi.org/10.5194/amt-17-1317-2024, https://doi.org/10.5194/amt-17-1317-2024, 2024
Short summary
Short summary
Using only low-cost microcontrollers and sensors, we constructed a measurement device to accurately and precisely obtain atmospheric carbon dioxide and water fluxes. The device was tested against known concentration increases and high-cost, commercial sensors during a laboratory and field experiment. We additionally tested the device over a longer period in a field study in Ghana during which the net ecosystem carbon balance and water use efficiency of maize cultivation were studied.
Adrian Dahlmann, Mathias Hoffmann, Gernot Verch, Marten Schmidt, Michael Sommer, Jürgen Augustin, and Maren Dubbert
Hydrol. Earth Syst. Sci., 27, 3851–3873, https://doi.org/10.5194/hess-27-3851-2023, https://doi.org/10.5194/hess-27-3851-2023, 2023
Short summary
Short summary
Evapotranspiration (ET) plays a pivotal role in terrestrial water cycling, returning up to 90 % of precipitation to the atmosphere. We studied impacts of soil type and management on an agroecosystem using an automated system with modern modeling approaches. We modeled ET at high spatial and temporal resolution to highlight differences in heterogeneous soils on an hourly basis. Our results show significant differences in yield and smaller differences in ET overall, impacting water use efficiency.
Doerthe Tetzlaff, Aaron Smith, Lukas Kleine, Hauke Daempfling, Jonas Freymueller, and Chris Soulsby
Earth Syst. Sci. Data, 15, 1543–1554, https://doi.org/10.5194/essd-15-1543-2023, https://doi.org/10.5194/essd-15-1543-2023, 2023
Short summary
Short summary
We present a comprehensive set of ecohydrological hydrometric and stable water isotope data of 2 years of data. The data set is unique as the different compartments of the landscape were sampled and the effects of a prolonged drought (2018–2020) captured by a marked negative rainfall anomaly (the most severe regional drought of the 21st century). Thus, the data allow the drought effects on water storage, flux and age dynamics, and persistence of lowland landscapes to be investigated.
Xiaoqiang Yang, Doerthe Tetzlaff, Chris Soulsby, and Dietrich Borchardt
Geosci. Model Dev. Discuss., https://doi.org/10.5194/gmd-2022-239, https://doi.org/10.5194/gmd-2022-239, 2022
Preprint retracted
Short summary
Short summary
We develop the catchment water quality assessment platform HiWaQ v1.0, which is compatible with multiple hydrological model structures. The nitrogen module (HiWaQ-N) and its coupling tests with two contrasting grid-based hydrological models demonstrate the robustness of the platform in estimating catchment N dynamics. With the unique design of the coupling flexibility, HiWaQ can leverage advancements in hydrological modelling and advance integrated catchment water quantity-quality assessments.
Guangxuan Li, Xi Chen, Zhicai Zhang, Lichun Wang, and Chris Soulsby
Hydrol. Earth Syst. Sci., 26, 5515–5534, https://doi.org/10.5194/hess-26-5515-2022, https://doi.org/10.5194/hess-26-5515-2022, 2022
Short summary
Short summary
We developed a coupled flow–tracer model to understand the effects of passive storage on modeling hydrological function and isotope dynamics in a karst flow system. Models with passive storages show improvement in matching isotope dynamics performance, and the improved performance also strongly depends on the number and location of passive storages. Our results also suggested that the solute transport is primarily controlled by advection and hydrodynamic dispersion in the steep hillslope unit.
Aaron Smith, Doerthe Tetzlaff, Jessica Landgraf, Maren Dubbert, and Chris Soulsby
Biogeosciences, 19, 2465–2485, https://doi.org/10.5194/bg-19-2465-2022, https://doi.org/10.5194/bg-19-2465-2022, 2022
Short summary
Short summary
This research utilizes high-spatiotemporal-resolution soil and vegetation measurements, including water stable isotopes, within an ecohydrological model to partition water flux dynamics and identify flow paths and durations. Results showed high vegetation water use and high spatiotemporal dynamics of vegetation water source and vegetation isotopes. The evaluation of these dynamics further revealed relatively fast flow paths through both shallow soil and vegetation.
Bernhard Aichner, David Dubbert, Christine Kiel, Katrin Kohnert, Igor Ogashawara, Andreas Jechow, Sarah-Faye Harpenslager, Franz Hölker, Jens Christian Nejstgaard, Hans-Peter Grossart, Gabriel Singer, Sabine Wollrab, and Stella Angela Berger
Earth Syst. Sci. Data, 14, 1857–1867, https://doi.org/10.5194/essd-14-1857-2022, https://doi.org/10.5194/essd-14-1857-2022, 2022
Short summary
Short summary
Water isotopes were measured along transects and in the form of time series in northeastern German lakes. The spatial patterns within the data and their seasonal variability are related to morphological and hydrological properties of the studied lake systems. They are further useful for the understanding of biogeochemical and ecological characteristics of these lakes.
Aaron J. Neill, Christian Birkel, Marco P. Maneta, Doerthe Tetzlaff, and Chris Soulsby
Hydrol. Earth Syst. Sci., 25, 4861–4886, https://doi.org/10.5194/hess-25-4861-2021, https://doi.org/10.5194/hess-25-4861-2021, 2021
Short summary
Short summary
Structural changes (cover and height of vegetation plus tree canopy characteristics) to forests during regeneration on degraded land affect how water is partitioned between streamflow, groundwater recharge and evapotranspiration. Partitioning most strongly deviates from baseline conditions during earlier stages of regeneration with dense forest, while recovery may be possible as the forest matures and opens out. This has consequences for informing sustainable landscape restoration strategies.
Mikael Gillefalk, Dörthe Tetzlaff, Reinhard Hinkelmann, Lena-Marie Kuhlemann, Aaron Smith, Fred Meier, Marco P. Maneta, and Chris Soulsby
Hydrol. Earth Syst. Sci., 25, 3635–3652, https://doi.org/10.5194/hess-25-3635-2021, https://doi.org/10.5194/hess-25-3635-2021, 2021
Short summary
Short summary
We used a tracer-aided ecohydrological model to quantify water flux–storage–age interactions for three urban vegetation types: trees, shrub and grass. The model results showed that evapotranspiration increased in the order shrub < grass < trees during one growing season. Additionally, we could show how
infiltration hotspotscreated by runoff from sealed onto vegetated surfaces can enhance both evapotranspiration and groundwater recharge.
Youri Rothfuss, Maria Quade, Nicolas Brüggemann, Alexander Graf, Harry Vereecken, and Maren Dubbert
Biogeosciences, 18, 3701–3732, https://doi.org/10.5194/bg-18-3701-2021, https://doi.org/10.5194/bg-18-3701-2021, 2021
Short summary
Short summary
The partitioning of evapotranspiration into evaporation from soil and transpiration from plants is crucial for a wide range of parties, from farmers to policymakers. In this work, we focus on a particular partitioning method, based on the stable isotopic analysis of water. In particular, we aim at highlighting the challenges that this method is currently facing and, in light of recent methodological developments, propose ways forward for the isotopic-partitioning community.
Aaron Smith, Doerthe Tetzlaff, Lukas Kleine, Marco Maneta, and Chris Soulsby
Hydrol. Earth Syst. Sci., 25, 2239–2259, https://doi.org/10.5194/hess-25-2239-2021, https://doi.org/10.5194/hess-25-2239-2021, 2021
Short summary
Short summary
We used a tracer-aided ecohydrological model on a mixed land use catchment in northeastern Germany to quantify water flux–storage–age interactions at four model grid resolutions. The model's ability to reproduce spatio-temporal flux–storage–age interactions decreases with increasing model grid sizes. Similarly, larger model grids showed vegetation-influenced changes in blue and green water partitioning. Simulations reveal the value of measured soil and stream isotopes for model calibration.
Jenna R. Snelgrove, James M. Buttle, Matthew J. Kohn, and Dörthe Tetzlaff
Hydrol. Earth Syst. Sci., 25, 2169–2186, https://doi.org/10.5194/hess-25-2169-2021, https://doi.org/10.5194/hess-25-2169-2021, 2021
Short summary
Short summary
Co-evolution of plant and soil water isotopic composition throughout the growing season in a little-studied northern mixed forest landscape was explored. Marked inter-specific differences in the isotopic composition of xylem water relative to surrounding soil water occurred, despite thin soil cover constraining inter-species differences in rooting depths. We provide potential explanations for differences in temporal evolution of xylem water isotopic composition in this northern landscape.
Lena-Marie Kuhlemann, Doerthe Tetzlaff, Aaron Smith, Birgit Kleinschmit, and Chris Soulsby
Hydrol. Earth Syst. Sci., 25, 927–943, https://doi.org/10.5194/hess-25-927-2021, https://doi.org/10.5194/hess-25-927-2021, 2021
Short summary
Short summary
We studied water partitioning under urban grassland, shrub and trees during a warm and dry growing season in Berlin, Germany. Soil evaporation was highest under grass, but total green water fluxes and turnover time of soil water were greater under trees. Lowest evapotranspiration losses under shrub indicate potential higher drought resilience. Knowledge of water partitioning and requirements of urban green will be essential for better adaptive management of urban water and irrigation strategies.
Cited articles
Barbeta, A. and Peñuelas, J.: Relative contribution of groundwater to plant transpiration estimated with stable isotopes, Sci. Rep., 7, 1–10, https://doi.org/10.1038/s41598-017-09643-x, 2017.
Barbeta, A., Gimeno, T. E., Clavé, L., Fréjaville, B., Jones, S. P., Delvigne, C., Wingate, L., and Ogée, J.: An explanation for the isotopic offset between soil and stem water in a temperate tree species, New Phytol., 227, 766–779, https://doi.org/10.1111/nph.16564, 2020.
Berry, Z. C., Evaristo, J., Moore, G., Poca, M., Steppe, K., Verrot, L., Asbjornsen, H., Borma, L. S., Bretfeld, M., Hervé-Fernández, P., Seyfried, M., Schwendenmann, L., Sinacore, K., De Wispelaere, L., and McDonnell, J.: The two water worlds hypothesis: Addressing multiple working hypotheses and proposing a way forward, Ecohydrology, 11, e1843, https://doi.org/10.1002/eco.1843, 2018.
Beyer, M., Hamutoko, J. T., Wanke, H., Gaj, M., and Koeniger, P.: Examination of deep root water uptake using anomalies of soil water stable isotopes, depth-controlled isotopic labeling and mixing models, J. Hydrol., 566, 122–136, https://doi.org/10.1016/j.jhydrol.2018.08.060, 2018.
Beyer, M., Kühnhammer, K., and Dubbert, M.: In situ measurements of soil and plant water isotopes: a review of approaches, practical considerations and a vision for the future, Hydrol. Earth Syst. Sci., 24, 4413–4440, https://doi.org/10.5194/hess-24-4413-2020, 2020.
Braden-Behrens, J., Markwitz, C., and Knohl, A.: Eddy covariance measurements of the dual-isotope composition of evapotranspiration, Agr. Forest Meteorol., 269, 203–219, https://doi.org/10.1016/j.agrformet.2019.01.035, 2019.
Brinkmann, N., Eugster, W., Zweifel, R., Buchmann, N., and Kahmen, A.: Temperate tree species show identical response in tree water deficit but different sensitivities in sap flow to summer soil drying, Tree Physiol., 36, 1508–1519, https://doi.org/10.1111/nph.15255, 2016.
Brooks, J. R., Barnard, H. R., Coulombe, R., and McDonnell, J. J.: Ecohydrologic separation of water between trees and streams in a Mediterranean climate, Nat. Geosci., 3, 100–104, https://doi.org/10.1038/NGEO722, 2010.
Burba, G.: Eddy covariance method for scientific, industrial, agricultural and regulatory applications: A field book on measuring ecosystem gas exchange and areal emission rates, LI-COR Biosciences, Nebraska, USA, ISBN 978-0-615-76827-4, 2013.
Burgess, S. S., Adams, M. A., Turner, N. C., Beverly, C. R., Ong, C. K., Khan, A. A., and Bleby, T. M.: An improved heat pulse method to measure low and reverse rates of sap flow in woody plants, Tree Physiol., 21, 589–598, https://doi.org/10.1093/treephys/21.9.589, 2001.
Butz, P., Hölscher, D., Cueva, E., and Graefe, S.: Tree water use patterns as influenced by phenology in a dry forest of Southern Ecuador, Front. Plant Sci., 9, 945, https://doi.org/10.3389/fpls.2018.00945, 2018.
Chen, Y., Helliker, B. R., Tang, X., Li, F., Zhou, Y., and Song, X.: Stem water cryogenic extraction biases estimation in deuterium isotope composition of plant source water, P. Natl. Acad. Sci. USA, 117, 33345–33350, https://doi.org/10.1073/pnas.2014422117, 2020.
Cunniff, J., Purdy, S. J., Barraclough, T. J., Castle, M., Maddison, A. L., Jones, L. E., Shield, I. F., Gregory, A. S., and Karp, A.: High yielding biomass genotypes of willow (Salix spp.) show differences in below ground biomass allocation, Biomass Bioenerg., 80, 114–127, https://doi.org/10.1016/j.biombioe.2015.04.020, 2015.
Dansgaard, W.: Stable isotopes in precipitation, Tellus, 16, 436–468, https://doi.org/10.3402/tellusa.v16i4.8993, 1964.
Dawson, T. E. and Ehleringer, J. R.: Streamside trees that do not use stream water, Nature, 350, 335–337, https://doi.org/10.1038/350335a0, 1991.
De Deurwaerder, H. P. T., Visser, M. D., Detto, M., Boeckx, P., Meunier, F., Kuehnhammer, K., Magh, R.-K., Marshall, J. D., Wang, L., Zhao, L., and Verbeeck, H.: Causes and consequences of pronounced variation in the isotope composition of plant xylem water, Biogeosciences, 17, 4853–4870, https://doi.org/10.5194/bg-17-4853-2020, 2020.
Deutscher Wetterdienst: DWD [data set], https://www.dwd.de/DE/leistungen/klimadatendeutschland/vielj_mittelwerte.html, last access: 16 November 2020a.
Deutscher Wetterdienst: DWD [data set], https://opendata.dwd.de/climate_environment/CDC/observations_germany/climate/daily/more_precip/recent/, last access: 16 November 2020b.
Driescher, E., Behrendt, H., Schellenberger, G., and Stellmacher, R.: Lake Müggelsee and its environment – natural conditions and anthropogenic impacts, Internationale Revue der gesamten Hydrobiologie und Hydrographie, 78, 327–343, 1993.
Dubbert, M., Piayda, A., Cuntz, M., Correia, A. C., Costa e Silva, F., Pereira, J. S., and Werner, C.: Stable oxygen isotope and flux partitioning demonstrates understory of an oak savanna contributes up to half of ecosystem carbon and water exchange, Front. Plant Sci., 5, 530, https://doi.org/10.3389/fpls.2014.00530, 2014.
Ehleringer, J. R. and Dawson, T. E.: Water uptake by plants: perspectives from stable isotope composition, Plant Cell Environ., 15, 1073–1082, https://doi.org/10.1111/j.1365-3040.1992.tb01657.x, 1992.
Evaristo, J., Jasechko, S., and McDonnell, J. J.: Global separation of plant transpiration from groundwater and streamflow, Nature, 525, 91–94, https://doi.org/10.1038/nature14983, 2015.
Friesen, J. and Van Stan, J. T.: Early European observations of precipitation partitioning by vegetation: a synthesis and evaluation of 19th century findings, Geosciences, 9, 423, https://doi.org/10.3390/geosciences9100423, 2019.
Gaj, M., Beyer, M., Koeniger, P., Wanke, H., Hamutoko, J., and Himmelsbach, T.: In situ unsaturated zone water stable isotope (2H and 18O) measurements in semi-arid environments: a soil water balance, Hydrol. Earth Syst. Sci., 20, 715–731, https://doi.org/10.5194/hess-20-715-2016, 2016.
Gessler, A., Bächli, L., Freund, E. R., Treydte, K., Schaub, M., Haeni, M., Weiler, M., Seeger, S., Marshall, J., Hug, C., Zweifel, R., Hagedorn, F., Rigling, A., Saurer, M., and Meusburger, K.: Drought reduces water uptake in beech form the drying topsoil, but no compensatory uptake occurs from deeper soil layers, New Phytol., 233, 194–206, https://doi.org/10.1111/nph.17767, 2022.
Goldsmith, G. R., Muñoz-Villers, L. E., Holwerda, F., McDonnell, J. J., Asbjornsen, H., and Dawson, T. E.: Stable isotopes reveal linkages among ecohydrological processes in a seasonally dry tropical montane cloud forest, Ecohydrology, 5, 779–790, https://doi.org/10.1002/eco.268, 2012.
Goldsmith, G. R., Allen, S. T., Braun, S., Engbersen, N., González-Quijano, C. R., Kirchner, J. W., and Siegwolf, R. T.: Spatial variation in throughfall, soil, and plant water isotopes in a temperate forest, Ecohydrology, 12, e2059, https://doi.org/10.1002/eco.2059, 2019.
Gralher, B., Herbstritt, B., Weiler, M., Wassenaar, L. I., and Stumpp, C.: Correcting laser-based water stable isotope readings biased by carrier gas changes, Environ. Sci. Technol., 50, 7074–7081, https://doi.org/10.1021/acs.est.6b01124, 2016.
Herbstritt, B., Gralher, B., and Weiler, M.: Continuous in situ measurements of stable isotopes in liquid water, Water Resour. Res., 48, W03601, https://doi.org/10.1029/2011WR011369, 2012.
Hertel, D., Strecker, T., Müller-Haubold, H., and Leuschner, C.: Fine root biomass and dynamics in beech forests across a precipitation gradient – is optimal resource partitioning theory applicable to water-limited mature trees?, J. Ecol., 101, 1183–1200, https://doi.org/10.1111/1365-2745.12124, 2013.
IAEA/GNIP: Precipitation sampling guide V2.02, September 2014.
Jackson, P. C., Cavelier, J., Goldstein, G., Meinzer, F. C., and Holbrook, N. M.: Partitioning of water resources among plants of a lowland tropical forest, Oecologia, 101, 197–203, https://www.jstor.org/stable/4220873, 1995.
Jasechko, S., Sharp, Z. D., Gibson, J. J., Birks, S. J., Yi, Y., and Fawcett, P. J.: Terrestrial water fluxes dominated by transpiration, Nature, 496, 347–350, https://doi.org/10.1038/nature11983, 2013.
Joshi, R., Wani, S. H., Singh, B., Bohra, A., Dar, Z. A., Lone, A. A., Pareek, A., and Singla-Pareek, S. L.: Transcription factors and plants response to drought stress: current understanding and future directions, Front. Plant Sci., 7, 1029, https://doi.org/10.3389/fpls.2016.01029, 2016.
Kleine, L., Tetzlaff, D., Smith, A., Wang, H., and Soulsby, C.: Using water stable isotopes to understand evaporation, moisture stress, and re-wetting in catchment forest and grassland soils of the summer drought of 2018, Hydrol. Earth Syst. Sci., 24, 3737–3752, https://doi.org/10.5194/hess-24-3737-2020, 2020.
Knighton, J., Kuppel, S., Smith, A., Soulsby, C., Sprenger, M., and Tetzlaff, D.: Using isotopes to incorporate tree water storage and mixing dynamics into a distributed ecohydrologic modelling framework, Ecohydrology, 13, e2201, https://doi.org/10.1002/eco.2201, 2020.
Koeniger, P., Marshall, J. D., Link, T., and Mulch, A.: An inexpensive, fast, and reliable method for vacuum extraction of soil and plant water for stable isotope analyses by mass spectrometry, Rapid Commun. Mass Sp., 25, 3041–3048, https://doi.org/10.1002/rcm.5198, 2011.
Kozii, N., Haahti, K., Tor-ngern, P., Chi, J., Hasselquist, E. M., Laudon, H., Launiainen, S., Oren, R., Peichl, M., Wallerman, J., and Hasselquist, N. J.: Partitioning growing season water balance within a forested boreal catchment using sap flux, eddy covariance, and a process-based model, Hydrol. Earth Syst. Sci., 24, 2999–3014, https://doi.org/10.5194/hess-24-2999-2020, 2020.
Kübert, A., Paulus, S., Dahlmann, A., Werner, C., Rothfuss, Y., Orlowski, N., and Dubbert, M.: Water stable isotopes in ecohydrological field research: Comparison between in situ and destructive monitoring methods to determine soil water isotopic signatures, Front. Plant Sci., 11, 387, https://doi.org/10.3389/fpls.2020.00387, 2020.
Kühnhammer, K., Kübert, A., Brüggemann, N., Deseano Diaz, P., van Dusschoten, D., Javaux, M., Merz, S., Vereecken, H., Dubbert, M., and Rothfuss, Y.: Investigating the root plasticity response of Centaurea jacea to soil water availability changes from isotopic analysis, New Phytol., 226, 98–110, https://doi.org/10.1111/nph.16352, 2020.
Kühnhammer, K., Dahlmann, A., Iraheta, A., Gerchow, M., Birkel, C., Marshall, J. D., and Beyer, M.: Continuous in situ measurements of water stable isotopes in soils, tree trunk and xylem: Field approval, Rapid Commun. Mass Sp., 36, e9232, https://doi.org/10.1002/rcm.9232, 2022.
Landwehr, J. M. M. and Coplen, T. B.: Line-conditioned excess: A new method for characterizing stable hydrogen and oxygen isotope ratios in hydrologic systems, International Conference on Isotopes in Environmental Studies, International Atomic Energy Agency (IAEA), 132–135, ISBN 92-0-111305-X, 2006.
Majoube, M.: Fractionnement en oxygène 18 et en deutérium entre l'eau et sa vapeur, J. Chim. Phys., 68, 1423–1436, 1971.
Marshall, D. C.: Measurement of sap flow in conifers by heat transport, Plant Physiol., 33, 385, 1958.
Marshall, J. D., Cuntz, M., Beyer, M., Dubbert, M., and Kuehnhammer, K.: Borehole equilibration: testing a new method to monitor the isotopic composition of tree xylem water in situ, Front. Plant Sci., 11, 358, https://doi.org/10.3389/fpls.2020.00358, 2020.
Martín-Gómez, P., Barbeta, A., Voltas, J., Peñuelas, J., Dennis, K., Palacio, S., Dawson, T. E., and Ferrio, J. P.: Isotope-ratio infrared spectroscopy: a reliable tool for the investigation of plant-water sources?, New Phytol., 207, 914–927, https://doi.org/10.1111/nph.13376, 2015.
Marttila, H., Dudley, B. D., Graham, S., and Srinivasan, M. S.: Does transpiration from invasive stream side willows dominate low-flow conditions? An investigation using hydrometric and isotopic methods in a headwater catchment, Ecohydrology, 11, e1930, https://doi.org/10.1002/eco.1930, 2017.
McCutcheon, R. J., McNamara, J. P., Kohn, M. J., and Evans, S. L.: An evaluation of the ecohydrological separation hypothesis in a semiarid catchment, Hydrol. Process., 31, 783–799, https://doi.org/10.1002/hyp.11052, 2017.
McDonnell, J. J., McGuire, K., Aggarwal, P., Beven, K. J., Biondi, D., Destouni, G., Dunn, S., James, A., Kirchner, J., Kraft, P., Lyon, S., Maloszewski, P., Newman, B., Pfister, L., Rinaldo, A., Rodhe, A., Sayama, T., Seibert, J., Solomon, K., Soulsby, C., Stewart, M., Tetzlaff, D., Tobin, C., Troch, P., Weiler, M., Western, A., Wörman, A., and Wrede, S.: How old is streamwater? Open questions in catchment transit time conceptualization, modeling and analysis, Hydrol. Process., 24, 1745–1754, https://doi.org/10.1002/wat2.1027, 2010.
Mencuccini, M., Hölttä, T., Sevanto, S., and Nikinmaa, E.:
Concurrent measurements of change in the bark and xylem diameters of
trees reveal a phloem-generated turgor signal, New Phytol., 198,
1143–1154, https://doi.org/10.1111/nph.12224, 2013.
Mennekes, D., Rinderer, M., Seeger, S., and Orlowski, N.: Ecohydrological travel times derived from in situ stable water isotope measurements in trees during a semi-controlled pot experiment, Hydrol. Earth Syst. Sci., 25, 4513–4530, https://doi.org/10.5194/hess-25-4513-2021, 2021.
Nehemy, M. F., Benettin, P., Asadollahi, M., Pratt, D., Rinaldo, A., and McDonnell, J. J.: Tree water deficit and dynamic source water partitioning, Hydrol. Process., 35, e14004, https://doi.org/10.1002/hyp.14004, 2021.
Oerter, E. J. and Bowen, G.: In situ monitoring of H and O stable isotopes in soil water reveals ecohydrologic dynamics in managed soil systems, Ecohydrology, 10, e1841, https://doi.org/10.1002/eco.1841, 2017.
OpenStreetMap contributors: https://www.openstreetmap.org/copyright, last access: 20 June 2020.
Orlowski, N., Breuer, L., and McDonnell, J. J.: Critical issues with cryogenic extraction of soil water for stable isotope analysis, Ecohydrology, 9, 1–5, https://doi.org/10.1002/eco.1722, 2016.
Paloschi, R. A., Ramos, D. M., Ventura, D. J., Souza, R., Souza, E., Morellato, L. P. C., Nóbrega, R. L. B., Coutinho, Í. A. C., Verhoef, A., Körting, T. S., and Borma, L. D. S.: Environmental Drivers of Water Use for Caatinga Woody Plant Species: Combining Remote Sensing Phenology and Sap Flow Measurements, Remote Sens., 13, 75, https://doi.org/10.3390/rs13010075, 2021.
Parnell, A. C., Inger, R., Bearhop, S., and Jackson, A. L.: Source partitioning using stable isotopes: coping with too much variation, PloS one, 5, e9672, https://doi.org/10.1371/journal.pone.0009672, 2010.
Phillips, D. L. and Gregg, J. W.: Source partitioning using stable isotopes: coping with too many sources, Oecologia, 136, 261–269, https://doi.org/10.1007/s00442-003-1218-3, 2003.
Rossiter, D. G.: Classification of urban and industrial soils in the world reference base for soil resources, J. Soil. Sediment., 7, 96–100, https://doi.org/10.1065/jss2007.02.208, 2007.
Rothfuss, Y. and Javaux, M.: Reviews and syntheses: Isotopic approaches to quantify root water uptake: a review and comparison of methods, Biogeosciences, 14, 2199–2224, https://doi.org/10.5194/bg-14-2199-2017, 2017.
Rothfuss, Y., Biron, P., Braud, I., Canale, L., Durand, J. L., Gaudet, J. P., Richard, P., Vauclin, M., and Bariac, T.: Partitioning evapotranspiration fluxes into soil evaporation and plant transpiration using water stable isotopes under controlled conditions, Hydrol. Process., 24, 3177–3194, https://doi.org/10.1002/hyp.7743, 2010.
Rothfuss, Y., Vereecken, H., and Brüggemann, N.: Monitoring water stable isotopic composition in soils using gas-permeable tubing and infrared laser absorption spectroscopy, Water Resour. Res., 49, 3747–3755, https://doi.org/10.1002/wrcr.20311, 2013.
Schaeffer, S. M., Williams, D. G., and Goodrich, D. C.: Transpiration of cottonwood/willow forest estimated from sap flux, Agr. Forest Meteorol., 105, 257–270, https://doi.org/10.1016/S0168-1923(00)00186-6, 2000.
Schmidt, M., Maseyk, K., Lett, C., Biron, P., Richard, P., Bariac, T., and Seibt, U.: Concentration effects on laser-based δ18O and δ2H measurements and implications for the calibration of vapour measurements with liquid standards, Rapid Commun. Mass Sp., 24, 3553–3561, https://doi.org/10.1002/rcm.4813, 2010.
Seeger, S. and Weiler, M.: Temporal dynamics of tree xylem water isotopes: in situ monitoring and modeling, Biogeosciences, 18, 4603–4627, https://doi.org/10.5194/bg-18-4603-2021, 2021.
Smith, A., Tetzlaff, D., Landgraf, J., Dubbert, M., and Soulsby, C.:
Modelling temporal variability of in-situ soil water and vegetation
isotopes reveals ecohydrological couplings in a willow plot,
Biogeosciences Discuss. [preprint], https://doi.org/10.5194/bg-2021-278, in
review, 2021.
Snelgrove, J. R., Buttle, J. M., Kohn, M. J., and Tetzlaff, D.: Co-evolution of xylem water and soil water stable isotopic composition in a northern mixed forest biome, Hydrol. Earth Syst. Sci., 25, 2169–2186, https://doi.org/10.5194/hess-25-2169-2021, 2021.
Sohel, M. S. I., Grau, A. V., McDonnell, J. J., and Herbohn, J.: Tropical forest water source patterns revealed by stable isotopes: A preliminary analysis of 46 neighboring species, Forest Ecol. Manag., 494, 119355, https://doi.org/10.1016/j.foreco.2021.119355, 2021.
Sprenger, M. and Allen, S. T.: What ecohydrologic separation is and where we can go with it, Water Resour. Res., 56, e2020WR027238, https://doi.org/10.1029/2020WR027238, 2020.
Sprenger, M., Stumpp, C., Weiler, M., Aeschbach, W., Allen, S. T., Benettin, P., Dubbert, M., Hartmann, A., Hrachowitz, M., Kirchner, J. W., McDonnell, J. J., Orlowski, N., Penna, D., Pfahl, S., Rinderer, M., Rodriguez, N., Schmidt, M., and Werner, C.: The demographics of water: A review of water ages in the critical zone, Rev. Geophys., 57, 800–834, https://doi.org/10.1029/2018RG000633, 2019.
STG (German Stratigraphic Commission): Stratigraphic Table of Germany 2016, – Potsdam
(German Research Centre for Geosciences),
(1) Table plain 100 × 141 cm, (2) Table folded A4, edited by: Menning, M. and Hendrich, A., 2016 (in German).
Stock, B. C., Jackson, A. L., Ward, E. J., Parnell, A. C., Phillips, D. L., and Semmens, B. X.: Analyzing mixing systems using a new generation of Bayesian tracer mixing models, PeerJ, 6, e5096, https://doi.org/10.7717/peerj.5096, 2018.
Süßel, F. and Brüggemann, W.: Tree water relations of mature oaks in southwest Germany under extreme drought stress in summer 2018, Plant Stress, 1, 100010, https://doi.org/10.1016/j.stress.2021.100010, 2021.
Tetzlaff, D., Buttle, J., Carey, S. K., Kohn, M. J., Laudon, H., McNamara, J. P., Smith, A., Sprenger, M., and Soulsby, C.: Stable isotopes of water reveal differences in plant–soil water relationships across northern environments, Hydrol. Process., 35, e14023, https://doi.org/10.1002/hyp.14023, 2021.
Thompson, S. E., Harman, C. J., Heine, P., and Katul, G. G.: Vegetation-infiltration relationships across climatic and soil type gradients, J. Geophys. Res., 115, G02023, https://doi.org/10.1029/2009JG001134, 2010.
Volkmann, T. H., Kühnhammer, K., Herbstritt, B., Gessler, A., and
Weiler, M.: A method for in situ monitoring of the isotope composition
of tree xylem water using laser spectroscopy, Plant Cell Environ., 39,
2055–2063, https://doi.org/10.1111/pce.12725, 2016a.
Volkmann, T. H., Haberer, K., Gessler, A., and Weiler, M.: High-resolution isotope measurements resolve rapid ecohydrological dynamics at the soil-plant interface, New Phytol., 210, 839–849, https://doi.org/10.1111/nph.13868, 2016b.
Volkmann, T. H. M. and Weiler, M.: Continual in situ monitoring of pore water stable isotopes in the subsurface, Hydrol. Earth Syst. Sci., 18, 1819–1833, https://doi.org/10.5194/hess-18-1819-2014, 2014.
von Freyberg, J., Allen, S. T., Grossiord, C., and Dawson, T. E.: Plant and root-zone water isotopes are difficult to measure, explain, and predict: Some practical recommendations for determining plant water sources, Methods Ecol. Evol., 11, 1352–1367, https://doi.org/10.1111/2041-210X.13461, 2020.
Wassenaar, L. I., Hendry, M. J., Chostner, V. L., and Lis, G. P.: 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.
West, A. G., Patrickson, S. J., and Ehleringer, J. R.: Water extraction times for plant and soil materials used in stable isotope analysis, Rapid Commun. Mass Sp., 20, 1317–1321, https://doi.org/10.1002/rcm.2456, 2006.
Williams, D. G., Cable, W., Hultine, K., Hoedjes, J. C. B., Yepez, E. A., Simonneaux, V., Er-Raki, S., Boulet, G., de Bruin, H. A. R., Chehbouni, A., Hartogensis, O. K., and Timouk, F.: Evapotranspiration components determined by stable isotope, sap flow and eddy covariance techniques, Agr. Forest Meteorol., 125, 241–258, https://doi.org/10.1016/j.agrformet.2004.04.008, 2004.
Yang, B., Wen, X., and Sun, X.: Seasonal variations in depth of water uptake for a subtropical coniferous plantation subjected to drought in an East Asian monsoon region, Agr. Forest Meteorol., 201, 218–228, https://doi.org/10.1016/j.agrformet.2014.11.020, 2015.
Zweifel, R.: Radial stem variations – a source of tree physiological information not fully exploited yet, Plant Cell Environ., 39, 231–232, https://doi.org/10.1111/pce.12613, 2016.
Zweifel, R., Zimmermann, L., and Newbery, D. M.: Modeling tree water deficit from microclimate: an approach to quantifying drought stress, Tree Physiol., 25, 147–156, https://doi.org/10.1093/treephys/25.2.147, 2005.
Short summary
Using water stable isotopes, we studied from which water source (lake water, stream water, groundwater, or soil water) two willows were taking their water. We monitored the environmental conditions (e.g. air temperature and soil moisture) and the behaviour of the trees (water flow in the stem). We found that the most likely water sources of the willows were the upper soil layers but that there were seasonal dynamics.
Using water stable isotopes, we studied from which water source (lake water, stream water,...
