Articles | Volume 20, issue 2
https://doi.org/10.5194/hess-20-715-2016
© Author(s) 2016. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
https://doi.org/10.5194/hess-20-715-2016
© Author(s) 2016. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Research article
| 
17 Feb 2016
Research article |
| 17 Feb 2016
In situ unsaturated zone water stable isotope (2H and 18O) measurements in semi-arid environments: a soil water balance
Federal Institue for Geosciences and Natural Resources
(BGR), Stilleweg 2, Hanover, Germany
Chair of Hydrology, Faculty of Environment and Natural
Resources, University of Freiburg, Fahnenbergplatz, 79098 Freiburg,
Germany
Matthias Beyer
Federal Institue for Geosciences and Natural Resources
(BGR), Stilleweg 2, Hanover, Germany
Paul Koeniger
Federal Institue for Geosciences and Natural Resources
(BGR), Stilleweg 2, Hanover, Germany
Heike Wanke
Department of Geology, University of Namibia (UNAM),
Windhoek, Namibia
Josefina Hamutoko
Department of Geology, University of Namibia (UNAM),
Windhoek, Namibia
Thomas Himmelsbach
Federal Institue for Geosciences and Natural Resources
(BGR), Stilleweg 2, Hanover, Germany
Related authors
Josefina Tulimevava Hamutoko, Heike Wanke, Matthias Beyer, Marcel Gaj, and Paul Koeniger
Proc. IAHS, 378, 29–35, https://doi.org/10.5194/piahs-378-29-2018, https://doi.org/10.5194/piahs-378-29-2018, 2018
Short summary
Short summary
The key finding was that groundwater chemistry of perched aquifers is controlled by dissolution of carbonate or evaporitic minerals, silicate weathering and ion exchange and stable isotopes signify recent recharge. Spatial and temporal variations indicate that groundwater from perched aquifers are chemically different reflecting the aquifer lithologies and hydrological landscape thus groundwater management practices should always be designed taking into account these specific characteristics.
Matthias Beyer, Kathrin Kühnhammer, and Maren Dubbert
Hydrol. Earth Syst. Sci., 24, 4413–4440, https://doi.org/10.5194/hess-24-4413-2020, https://doi.org/10.5194/hess-24-4413-2020, 2020
Short summary
Short summary
Water isotopes are a scientific tool that can be used to identify sources of water and answer questions such as
From which soil depths do plants take up water?, which are highly relevant under changing climatic conditions. In the past, the measurement of water isotopes required tremendous effort. In the last decade methods have advanced and can now be applied in the field. Herein, we review the current status of direct field measurements of water isotopes and discuss future applications.
Daniele Penna, Luisa Hopp, Francesca Scandellari, Scott T. Allen, Paolo Benettin, Matthias Beyer, Josie Geris, Julian Klaus, John D. Marshall, Luitgard Schwendenmann, Till H. M. Volkmann, Jana von Freyberg, Anam Amin, Natalie Ceperley, Michael Engel, Jay Frentress, Yamuna Giambastiani, Jeff J. McDonnell, Giulia Zuecco, Pilar Llorens, Rolf T. W. Siegwolf, Todd E. Dawson, and James W. Kirchner
Biogeosciences, 15, 6399–6415, https://doi.org/10.5194/bg-15-6399-2018, https://doi.org/10.5194/bg-15-6399-2018, 2018
Short summary
Short summary
Understanding how water flows through ecosystems is needed to provide society and policymakers with the scientific background to manage water resources sustainably. Stable isotopes of hydrogen and oxygen in water are a powerful tool for tracking water fluxes, although the heterogeneity of natural systems and practical methodological issues still limit their full application. Here, we examine the challenges in this research field and highlight new perspectives based on interdisciplinary research.
Natalie Orlowski, Lutz Breuer, Nicolas Angeli, Pascal Boeckx, Christophe Brumbt, Craig S. Cook, Maren Dubbert, Jens Dyckmans, Barbora Gallagher, Benjamin Gralher, Barbara Herbstritt, Pedro Hervé-Fernández, Christophe Hissler, Paul Koeniger, Arnaud Legout, Chandelle Joan Macdonald, Carlos Oyarzún, Regine Redelstein, Christof Seidler, Rolf Siegwolf, Christine Stumpp, Simon Thomsen, Markus Weiler, Christiane Werner, and Jeffrey J. McDonnell
Hydrol. Earth Syst. Sci., 22, 3619–3637, https://doi.org/10.5194/hess-22-3619-2018, https://doi.org/10.5194/hess-22-3619-2018, 2018
Short summary
Short summary
To extract water from soils for isotopic analysis, cryogenic water extraction is the most widely used removal technique. This work presents results from a worldwide laboratory intercomparison test of cryogenic extraction systems. Our results showed large differences in retrieved isotopic signatures among participating laboratories linked to interactions between soil type and properties, system setup, extraction efficiency, extraction system leaks, and each lab’s internal accuracy.
Josefina Tulimevava Hamutoko, Heike Wanke, Matthias Beyer, Marcel Gaj, and Paul Koeniger
Proc. IAHS, 378, 29–35, https://doi.org/10.5194/piahs-378-29-2018, https://doi.org/10.5194/piahs-378-29-2018, 2018
Short summary
Short summary
The key finding was that groundwater chemistry of perched aquifers is controlled by dissolution of carbonate or evaporitic minerals, silicate weathering and ion exchange and stable isotopes signify recent recharge. Spatial and temporal variations indicate that groundwater from perched aquifers are chemically different reflecting the aquifer lithologies and hydrological landscape thus groundwater management practices should always be designed taking into account these specific characteristics.
Related subject area
Subject: Vadose Zone Hydrology | Techniques and Approaches: Instruments and observation techniques
High-resolution operational soil moisture monitoring for forests in central Germany
Technical Note: Revisiting the general calibration of cosmic-ray neutron sensors to estimate soil water content
Coupled hydrogeophysical inversion of an artificial infiltration experiment monitored with ground-penetrating radar: synthetic demonstration
Technical note: Discrete in situ vapor sampling for subsequent lab-based water stable isotope analysis
A change in perspective: downhole cosmic-ray neutron sensing for the estimation of soil moisture
Impacts of soil management and climate on saturated and near-saturated hydraulic conductivity: analyses of the Open Tension-disk Infiltrometer Meta-database (OTIM)
Physics-informed machine learning for understanding rock moisture dynamics in a sandstone cave
Relationship of seasonal variations in drip water δ13CDIC, δ18O, and trace elements with surface and physical cave conditions of La Vallina cave, NW Spain
In situ estimation of soil hydraulic and hydrodispersive properties by inversion of electromagnetic induction measurements and soil hydrological modeling
Towards disentangling heterogeneous soil moisture patterns in cosmic-ray neutron sensor footprints
The International Soil Moisture Network: serving Earth system science for over a decade
Technical note: Evaporating water is different from bulk soil water in δ2H and δ18O and has implications for evaporation calculation
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
Spatio-temporal soil moisture retrieval at the catchment scale using a dense network of cosmic-ray neutron sensors
Deep desiccation of soils observed by long-term high-resolution measurements on a large inclined lysimeter
A novel analytical approach for the simultaneous measurement of nitrate and dissolved organic carbon in soil water
Exploring the regolith with electrical resistivity tomography in large-scale surveys: electrode spacing-related issues and possibility
Soil dielectric characterization during freeze–thaw transitions using L-band coaxial and soil moisture probes
Hydrological signals in tilt and gravity residuals at Conrad Observatory (Austria)
New measures of deep soil water recharge during the vegetation restoration process in semi-arid regions of northern China
Estimation of subsurface soil moisture from surface soil moisture in cold mountainous areas
Investigating unproductive water losses from irrigated agricultural crops in the humid tropics through analyses of stable isotopes of water
Pacific climate reflected in Waipuna Cave drip water hydrochemistry
Field observations of soil hydrological flow path evolution over 10 millennia
A proposed method for estimating interception from near-surface soil moisture response
Controls of fluorescent tracer retention by soils and sediments
Reflection tomography of time-lapse GPR data for studying dynamic unsaturated flow phenomena
Effects of preferential flow on snowmelt partitioning and groundwater recharge in frozen soils
Spatio-temporal relevance and controls of preferential flow at the landscape scale
Real-time monitoring of nitrate in soils as a key for optimization of agricultural productivity and prevention of groundwater pollution
A soil non-aqueous phase liquid (NAPL) flushing laboratory experiment based on measuring the dielectric properties of soil–organic mixtures via time domain reflectometry (TDR)
The value of satellite remote sensing soil moisture data and the DISPATCH algorithm in irrigation fields
Estimating epikarst water storage by time-lapse surface-to-depth gravity measurements
Inter-laboratory comparison of cryogenic water extraction systems for stable isotope analysis of soil water
Preferential flow systems amended with biogeochemical components: imaging of a two-dimensional study
Imaging groundwater infiltration dynamics in the karst vadose zone with long-term ERT monitoring
Calibrating electromagnetic induction conductivities with time-domain reflectometry measurements
Multiscale soil moisture estimates using static and roving cosmic-ray soil moisture sensors
Field-scale water balance closure in seasonally frozen conditions
Improving calibration and validation of cosmic-ray neutron sensors in the light of spatial sensitivity
Is annual recharge coefficient a valid concept in arid and semi-arid regions?
Transport and degradation of perchlorate in deep vadose zone: implications from direct observations during bioremediation treatment
Monitoring soil moisture from middle to high elevation in Switzerland: set-up and first results from the SOMOMOUNT network
Experimental study on retardation of a heavy NAPL vapor in partially saturated porous media
Repeated electromagnetic induction measurements for mapping soil moisture at the field scale: validation with data from a wireless soil moisture monitoring network
ENSO–cave drip water hydrochemical relationship: a 7-year dataset from south-eastern Australia
Incorporation of globally available datasets into the roving cosmic-ray neutron probe method for estimating field-scale soil water content
Real-time monitoring of nitrate transport in the deep vadose zone under a crop field – implications for groundwater protection
Technical note: Improving the AWAT filter with interpolation schemes for advanced processing of high resolution data
Estimating field-scale root zone soil moisture using the cosmic-ray neutron probe
Ivan Vorobevskii, Thi Thanh Luong, Rico Kronenberg, and Rainer Petzold
Hydrol. Earth Syst. Sci., 28, 3567–3595, https://doi.org/10.5194/hess-28-3567-2024, https://doi.org/10.5194/hess-28-3567-2024, 2024
Short summary
Short summary
An introduced high-resolution soil moisture monitoring framework combines a 1D water balance model, real-time meteorological data, and a national soil database to present point-based operational data with a user-friendly web platform. Its significance lies in the improvement of forest management by making informed, local-scale decisions crucial for mitigating climate change impacts. In the paper, we present a technical description and validation of the framework and showcase its features.
Maik Heistermann, Till Francke, Martin Schrön, and Sascha E. Oswald
Hydrol. Earth Syst. Sci., 28, 989–1000, https://doi.org/10.5194/hess-28-989-2024, https://doi.org/10.5194/hess-28-989-2024, 2024
Short summary
Short summary
Cosmic-ray neutron sensing (CRNS) is a non-invasive technique used to obtain estimates of soil water content (SWC) at a horizontal footprint of around 150 m and a vertical penetration depth of up to 30 cm. However, typical CRNS applications require the local calibration of a function which converts neutron counts to SWC. As an alternative, we propose a generalized function as a way to avoid the use of local reference measurements of SWC and hence a major source of uncertainty.
Rohianuu Moua, Nolwenn Lesparre, Jean-François Girard, Benjamin Belfort, François Lehmann, and Anis Younes
Hydrol. Earth Syst. Sci., 27, 4317–4334, https://doi.org/10.5194/hess-27-4317-2023, https://doi.org/10.5194/hess-27-4317-2023, 2023
Short summary
Short summary
Hydraulic properties of soil include the ability of water to move through the soil and the amount of water that is held in the soil in dry or wet conditions. In this work, we further investigate a protocol used to evaluate such hydraulic properties. We propose a modified version of the protocol, with which we show (i) how the data obtained with this protocol are influenced by the soil hydraulic properties and (ii) how one can use it to estimate these properties.
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.
Daniel Rasche, Jannis Weimar, Martin Schrön, Markus Köhli, Markus Morgner, Andreas Güntner, and Theresa Blume
Hydrol. Earth Syst. Sci., 27, 3059–3082, https://doi.org/10.5194/hess-27-3059-2023, https://doi.org/10.5194/hess-27-3059-2023, 2023
Short summary
Short summary
We introduce passive downhole cosmic-ray neutron sensing (d-CRNS) as an approach for the non-invasive estimation of soil moisture in deeper layers of the unsaturated zone which exceed the observational window of above-ground CRNS applications. Neutron transport simulations are used to derive mathematical descriptions and transfer functions, while experimental measurements in an existing groundwater observation well illustrate the feasibility and applicability of the approach.
Guillaume Blanchy, Lukas Albrecht, Gilberto Bragato, Sarah Garré, Nicholas Jarvis, and John Koestel
Hydrol. Earth Syst. Sci., 27, 2703–2724, https://doi.org/10.5194/hess-27-2703-2023, https://doi.org/10.5194/hess-27-2703-2023, 2023
Short summary
Short summary
We collated the Open Tension-disk Infiltrometer Meta-database (OTIM). We analysed topsoil hydraulic conductivities at supply tensions between 0 and 100 mm of 466 data entries. We found indications of different flow mechanisms at saturation and at tensions >20 mm. Climate factors were better correlated with near-saturated hydraulic conductivities than soil properties. Land use, tillage system, soil compaction and experimenter bias significantly influenced K to a similar degree to soil properties.
Kai-Gao Ouyang, Xiao-Wei Jiang, Gang Mei, Hong-Bin Yan, Ran Niu, Li Wan, and Yijian Zeng
Hydrol. Earth Syst. Sci., 27, 2579–2590, https://doi.org/10.5194/hess-27-2579-2023, https://doi.org/10.5194/hess-27-2579-2023, 2023
Short summary
Short summary
Our knowledge on sources and dynamics of rock moisture is limited. By using frequency domain reflectometry (FDR), we monitored rock moisture in a cave. The results of an explainable deep learning model reveal that the direct source of rock moisture responsible for weathering in the studied cave is vapour, not infiltrating precipitation. A physics-informed deep learning model, which uses variables controlling vapor condensation as model inputs, leads to accurate rock water content predictions.
Oliver Kost, Saúl González-Lemos, Laura Rodríguez-Rodríguez, Jakub Sliwinski, Laura Endres, Negar Haghipour, and Heather Stoll
Hydrol. Earth Syst. Sci., 27, 2227–2255, https://doi.org/10.5194/hess-27-2227-2023, https://doi.org/10.5194/hess-27-2227-2023, 2023
Short summary
Short summary
Cave monitoring studies including cave drip water are unique opportunities to sample water which has percolated through the soil and rock. The change in drip water chemistry is resolved over the course of 16 months, inferring seasonal and hydrological variations in soil and karst processes at the water–air and water–rock interface. Such data sets improve the understanding of hydrological and hydrochemical processes and ultimately advance the interpretation of geochemical stalagmite records.
Giovanna Dragonetti, Mohammad Farzamian, Angelo Basile, Fernando Monteiro Santos, and Antonio Coppola
Hydrol. Earth Syst. Sci., 26, 5119–5136, https://doi.org/10.5194/hess-26-5119-2022, https://doi.org/10.5194/hess-26-5119-2022, 2022
Short summary
Short summary
Soil hydraulic and hydrodispersive properties are necessary for modeling water and solute fluxes in agricultural and environmental systems. Despite the major efforts in developing methods (e.g., lab-based, pedotransfer functions), their characterization at applicative scales remains an imperative requirement. Thus, this paper proposes a noninvasive in situ method integrating electromagnetic induction and hydrological modeling to estimate soil hydraulic and transport properties at the plot scale.
Daniel Rasche, Markus Köhli, Martin Schrön, Theresa Blume, and Andreas Güntner
Hydrol. Earth Syst. Sci., 25, 6547–6566, https://doi.org/10.5194/hess-25-6547-2021, https://doi.org/10.5194/hess-25-6547-2021, 2021
Short summary
Short summary
Cosmic-ray neutron sensing provides areal average soil moisture measurements. We investigated how distinct differences in spatial soil moisture patterns influence the soil moisture estimates and present two approaches to improve the estimate of soil moisture close to the instrument by reducing the influence of soil moisture further afield. Additionally, we show that the heterogeneity of soil moisture can be assessed based on the relationship of different neutron energies.
Wouter Dorigo, Irene Himmelbauer, Daniel Aberer, Lukas Schremmer, Ivana Petrakovic, Luca Zappa, Wolfgang Preimesberger, Angelika Xaver, Frank Annor, Jonas Ardö, Dennis Baldocchi, Marco Bitelli, Günter Blöschl, Heye Bogena, Luca Brocca, Jean-Christophe Calvet, J. Julio Camarero, Giorgio Capello, Minha Choi, Michael C. Cosh, Nick van de Giesen, Istvan Hajdu, Jaakko Ikonen, Karsten H. Jensen, Kasturi Devi Kanniah, Ileen de Kat, Gottfried Kirchengast, Pankaj Kumar Rai, Jenni Kyrouac, Kristine Larson, Suxia Liu, Alexander Loew, Mahta Moghaddam, José Martínez Fernández, Cristian Mattar Bader, Renato Morbidelli, Jan P. Musial, Elise Osenga, Michael A. Palecki, Thierry Pellarin, George P. Petropoulos, Isabella Pfeil, Jarrett Powers, Alan Robock, Christoph Rüdiger, Udo Rummel, Michael Strobel, Zhongbo Su, Ryan Sullivan, Torbern Tagesson, Andrej Varlagin, Mariette Vreugdenhil, Jeffrey Walker, Jun Wen, Fred Wenger, Jean Pierre Wigneron, Mel Woods, Kun Yang, Yijian Zeng, Xiang Zhang, Marek Zreda, Stephan Dietrich, Alexander Gruber, Peter van Oevelen, Wolfgang Wagner, Klaus Scipal, Matthias Drusch, and Roberto Sabia
Hydrol. Earth Syst. Sci., 25, 5749–5804, https://doi.org/10.5194/hess-25-5749-2021, https://doi.org/10.5194/hess-25-5749-2021, 2021
Short summary
Short summary
The International Soil Moisture Network (ISMN) is a community-based open-access data portal for soil water measurements taken at the ground and is accessible at https://ismn.earth. Over 1000 scientific publications and thousands of users have made use of the ISMN. The scope of this paper is to inform readers about the data and functionality of the ISMN and to provide a review of the scientific progress facilitated through the ISMN with the scope to shape future research and operations.
Hongxiu Wang, Jingjing Jin, Buli Cui, Bingcheng Si, Xiaojun Ma, and Mingyi Wen
Hydrol. Earth Syst. Sci., 25, 5399–5413, https://doi.org/10.5194/hess-25-5399-2021, https://doi.org/10.5194/hess-25-5399-2021, 2021
Short summary
Short summary
Evaporation led to progressively more heavy-isotope-enriched bulk soil water (BW) following the precipitation/irrigation of heavy-isotope-depleted new water but causes progressively more heavy-isotope-depleted BW following irrigation of heavy-isotope-enriched new water. The results indicated that δ2H and δ18O in evaporating water (EW) were similar to new water and differed from BW. However, the evaporative water loss calculated from BW did not differ significantly from that of EW.
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.
Maik Heistermann, Till Francke, Martin Schrön, and Sascha E. Oswald
Hydrol. Earth Syst. Sci., 25, 4807–4824, https://doi.org/10.5194/hess-25-4807-2021, https://doi.org/10.5194/hess-25-4807-2021, 2021
Short summary
Short summary
Cosmic-ray neutron sensing (CRNS) is a powerful technique for retrieving representative estimates of soil moisture in footprints extending over hectometres in the horizontal and decimetres in the vertical. This study, however, demonstrates the potential of CRNS to obtain spatio-temporal patterns of soil moisture beyond isolated footprints. To that end, we analyse data from a unique observational campaign that featured a dense network of more than 20 neutron detectors in an area of just 1 km2.
Markus Merk, Nadine Goeppert, and Nico Goldscheider
Hydrol. Earth Syst. Sci., 25, 3519–3538, https://doi.org/10.5194/hess-25-3519-2021, https://doi.org/10.5194/hess-25-3519-2021, 2021
Short summary
Short summary
Soil moisture levels have decreased significantly over the past 2 decades. This decrease is not uniformly distributed over the observation period. The largest changes occur at tipping points during years of extreme drought, after which soil moisture levels reach significantly different alternate stable states. Not only the overall trend in soil moisture is affected, but also the seasonal dynamics.
Elad Yeshno, Ofer Dahan, Shoshana Bernstain, and Shlomi Arnon
Hydrol. Earth Syst. Sci., 25, 2159–2168, https://doi.org/10.5194/hess-25-2159-2021, https://doi.org/10.5194/hess-25-2159-2021, 2021
Short summary
Short summary
In this research, we present a novel approach, enabling the measurement of nitrate concentrations in natural soil porewater containing natural soil dissolved organic carbon. This method can be used as the basis onto which an affordable and miniaturized nitrate monitoring sensor for soils can be developed. This sensor can play a significant role in reducing nitrate pollution in water resources, optimizing fertilizers application during agricultural activity and decreasing food production costs.
Laurent Gourdol, Rémi Clément, Jérôme Juilleret, Laurent Pfister, and Christophe Hissler
Hydrol. Earth Syst. Sci., 25, 1785–1812, https://doi.org/10.5194/hess-25-1785-2021, https://doi.org/10.5194/hess-25-1785-2021, 2021
Short summary
Short summary
Electrical resistivity tomography (ERT) is a remarkable tool for characterizing the regolith, but its use over large areas remains cumbersome due to the requirement of small electrode spacing (ES). In this study we document the issues of using oversized ESs and propose a new approach to overcome this limitation. We demonstrate that our protocol significantly improves the accuracy of ERT profiles using large ES and offers a cost-effective means for carrying out large-scale surveys.
Alex Mavrovic, Renato Pardo Lara, Aaron Berg, François Demontoux, Alain Royer, and Alexandre Roy
Hydrol. Earth Syst. Sci., 25, 1117–1131, https://doi.org/10.5194/hess-25-1117-2021, https://doi.org/10.5194/hess-25-1117-2021, 2021
Short summary
Short summary
This paper presents a new probe that measures soil microwave permittivity in the frequency range of satellite L-band sensors. The probe capacities will allow for validation and calibration of the models used to estimate landscape physical properties from raw microwave satellite datasets. Our results show important discrepancies between model estimates and instrument measurements that will need to be addressed.
Bruno Meurers, Gábor Papp, Hannu Ruotsalainen, Judit Benedek, and Roman Leonhardt
Hydrol. Earth Syst. Sci., 25, 217–236, https://doi.org/10.5194/hess-25-217-2021, https://doi.org/10.5194/hess-25-217-2021, 2021
Short summary
Short summary
Gravity and tilt time series acquired at Conrad Observatory (Austria) reflect gravity and deformation associated with short- and long-term environmental processes, revealing a complex water transport process after heavy rain and rapid snowmelt. Gravity residuals are sensitive to the Newtonian effect of water mass transport. Tilt residual anomalies capture strain–tilt coupling effects due to surface or subsurface deformation from precipitation or pressure changes in the adjacent fracture system.
Yiben Cheng, Xinle Li, Yunqi Wang, Hongbin Zhan, Wenbin Yang, and Qunou Jiang
Hydrol. Earth Syst. Sci., 24, 5875–5890, https://doi.org/10.5194/hess-24-5875-2020, https://doi.org/10.5194/hess-24-5875-2020, 2020
Short summary
Short summary
The Three North Forest Program has produced a vast area of lined forest in semi-arid regions, which consumes a large amount of water resources. This study uses a newly designed lysimeter to measure water distribution without destroying the in situ vegetation soil structure. It addresses the shortcomings of a traditional lysimeter, in terms of changing the in situ soil structure and destroying the vegetation root system, and the shortcomings of high costs and inconvenient installation.
Jie Tian, Zhibo Han, Heye Reemt Bogena, Johan Alexander Huisman, Carsten Montzka, Baoqing Zhang, and Chansheng He
Hydrol. Earth Syst. Sci., 24, 4659–4674, https://doi.org/10.5194/hess-24-4659-2020, https://doi.org/10.5194/hess-24-4659-2020, 2020
Short summary
Short summary
Large-scale profile soil moisture (SM) is important for water resource management, but its estimation is a challenge. Thus, based on in situ SM observations in a cold mountain, a strong relationship between the surface SM and subsurface SM is found. Both the subsurface SM of 10–30 cm and the profile SM of 0–70 cm can be estimated from the surface SM of 0–10 cm accurately. By combing with the satellite product, we improve the large-scale profile SM estimation in the cold mountains finally.
Amani Mahindawansha, Christoph Külls, Philipp Kraft, and Lutz Breuer
Hydrol. Earth Syst. Sci., 24, 3627–3642, https://doi.org/10.5194/hess-24-3627-2020, https://doi.org/10.5194/hess-24-3627-2020, 2020
Short summary
Short summary
Stable isotopes of soil water are an effective tool to reveal soil hydrological processes in irrigated agricultural fields. Flow mechanisms and isotopic patterns of soil water in the soil matrix differ, depending on the crop and irrigation practices. Isotope data supported the fact that unproductive water losses via evaporation can be reduced by introducing dry seasonal crops to the crop rotation system.
Cinthya Nava-Fernandez, Adam Hartland, Fernando Gázquez, Ola Kwiecien, Norbert Marwan, Bethany Fox, John Hellstrom, Andrew Pearson, Brittany Ward, Amanda French, David A. Hodell, Adrian Immenhauser, and Sebastian F. M. Breitenbach
Hydrol. Earth Syst. Sci., 24, 3361–3380, https://doi.org/10.5194/hess-24-3361-2020, https://doi.org/10.5194/hess-24-3361-2020, 2020
Short summary
Short summary
Speleothems are powerful archives of past climate for understanding modern local hydrology and its relation to regional circulation patterns. We use a 3-year monitoring dataset to test the sensitivity of Waipuna Cave to seasonal changes and El Niño–Southern Oscillation (ENSO) dynamics. Drip water data suggest a fast response to rainfall events; its elemental composition reflects a seasonal cycle and ENSO variability. Waipuna Cave speleothems have a high potential for past ENSO reconstructions.
Anne Hartmann, Ekaterina Semenova, Markus Weiler, and Theresa Blume
Hydrol. Earth Syst. Sci., 24, 3271–3288, https://doi.org/10.5194/hess-24-3271-2020, https://doi.org/10.5194/hess-24-3271-2020, 2020
Short summary
Short summary
Our field observation-based examination of flow path evolution, soil formation, and vegetation succession across 10 millennia shows how water flow paths and subsurface water storage are linked to the organization of evolving landscapes.
The increase found in water storage and preferential flow paths with increasing soil age shows the effect of the complex interaction of vegetation and soil development on flow paths, water balance, and runoff formation during landscape evolution.
Subodh Acharya, Daniel McLaughlin, David Kaplan, and Matthew J. Cohen
Hydrol. Earth Syst. Sci., 24, 1859–1870, https://doi.org/10.5194/hess-24-1859-2020, https://doi.org/10.5194/hess-24-1859-2020, 2020
Short summary
Short summary
Interception is the storage and subsequent evaporation of rain by vegetation and surface litter. Quantifying interception is critical for understanding the water balance, but it can be difficult and costly to measure. We developed an approach to estimate interception using automated soil moisture measurements during rainfall events. Results suggest that interception can be estimated using soil moisture data, leading to potential cost savings and logistical advantages over conventional methods.
Marcus Bork, Jens Lange, Markus Graf-Rosenfellner, and Friederike Lang
Hydrol. Earth Syst. Sci., 24, 977–989, https://doi.org/10.5194/hess-24-977-2020, https://doi.org/10.5194/hess-24-977-2020, 2020
Short summary
Short summary
Fluorescent tracers such as uranine and sulforhodamine B are useful tools to gain knowledge about water and solute fluxes in aquatic and terrestrial ecosystems. In this study we systematically investigated the influence of important soil properties (pH, organic carbon content and texture) on tracer adsorption in soils and sediments. These properties also determine whether the tracers in the respective soil behave conservatively or non-conservatively.
Adam R. Mangel, Stephen M. J. Moysey, and John Bradford
Hydrol. Earth Syst. Sci., 24, 159–167, https://doi.org/10.5194/hess-24-159-2020, https://doi.org/10.5194/hess-24-159-2020, 2020
Short summary
Short summary
Water flows through soils in an incredibly complex network of pathways. Understanding these pathways is critical to sustainable use of water resources. Ground-penetrating radar (GPR) can image water in near-surface soils the same way an X-ray is used to image the human body. Utilizing innovative ways of collecting and processing the GPR data, we can image complex water flow in space and through time, which allows for the continued development of our ideas and models of subsurface water flow.
Aaron A. Mohammed, Igor Pavlovskii, Edwin E. Cey, and Masaki Hayashi
Hydrol. Earth Syst. Sci., 23, 5017–5031, https://doi.org/10.5194/hess-23-5017-2019, https://doi.org/10.5194/hess-23-5017-2019, 2019
Short summary
Short summary
In cold regions, the permeability of the frozen ground is an important factor influencing a watershed's response to snowmelt. This study highlights the effects of preferential flow in frozen soils on snowmelt redistribution and groundwater recharge in seasonally frozen landscapes.
Dominic Demand, Theresa Blume, and Markus Weiler
Hydrol. Earth Syst. Sci., 23, 4869–4889, https://doi.org/10.5194/hess-23-4869-2019, https://doi.org/10.5194/hess-23-4869-2019, 2019
Short summary
Short summary
This study presents an analysis of 135 soil moisture profiles for identification of the spatial and temporal preferential flow occurrence in a complex landscape. Especially dry conditions and high rainfall intensities were found to increase preferential flow occurrence in soils. This results in a seasonal pattern of preferential flow with a higher occurrence in summer. During this time grasslands showed increased flow velocities, whereas forest sites exhibited a higher amount of bypass flow.
Elad Yeshno, Shlomi Arnon, and Ofer Dahan
Hydrol. Earth Syst. Sci., 23, 3997–4010, https://doi.org/10.5194/hess-23-3997-2019, https://doi.org/10.5194/hess-23-3997-2019, 2019
Short summary
Short summary
Lack of adequate instrumentation for monitoring nutrient availability in agricultural soils leads in most cases to over-application of fertilizers, often resulting in groundwater pollution. This research presents a novel approach for real-time, in situ monitoring of nitrate in soils using absorption spectroscopy techniques while preventing interference from dissolved organic carbon. Column experiments with this system resulted in accurate nitrate measurements in three different soil types.
Alessandro Comegna, Antonio Coppola, Giovanna Dragonetti, and Angelo Sommella
Hydrol. Earth Syst. Sci., 23, 3593–3602, https://doi.org/10.5194/hess-23-3593-2019, https://doi.org/10.5194/hess-23-3593-2019, 2019
Short summary
Short summary
We carried out a series of laboratory-controlled experiments in order to simulate different scenarios of practical interest aiming to analyze, from a dielectric point of view, the influence of different washing solutions on non-aqueous phase liquid (NAPL) removal. Furthermore, on the basis of the results obtained, we validated a dielectric mixing model for predicting the volumetric amounts of NAPL (θNAPL) within the contaminated soil as the decontamination process progressed.
Mireia Fontanet, Daniel Fernàndez-Garcia, and Francesc Ferrer
Hydrol. Earth Syst. Sci., 22, 5889–5900, https://doi.org/10.5194/hess-22-5889-2018, https://doi.org/10.5194/hess-22-5889-2018, 2018
Short summary
Short summary
One of the main objectives of remote sensing methodology is to downscale soil moisture to improve irrigation management. The DISPATCH algorithm is able to measure soil moisture at 1 km resolution using SMOS and MODIS data. In this work DISPATCH has been evaluated with soil moisture sensors, under heterogeneous conditions where local irrigation is applied. Results show that DISPATCH is not sensitive when local irrigation is applied even at low resolution.
Cédric Champollion, Sabrina Deville, Jean Chéry, Erik Doerflinger, Nicolas Le Moigne, Roger Bayer, Philippe Vernant, and Naomi Mazzilli
Hydrol. Earth Syst. Sci., 22, 3825–3839, https://doi.org/10.5194/hess-22-3825-2018, https://doi.org/10.5194/hess-22-3825-2018, 2018
Short summary
Short summary
Gravity monitoring at the surface and in situ (in caves) has been conducted in a karst hydro-system in the south of France (Larzac plateau). Subsurface water storage is evidenced with a spatial variability probably associated with lithology differences and confirmed by MRS measurements. Gravity allows transient water storage to be estimated on the seasonal scale.
Natalie Orlowski, Lutz Breuer, Nicolas Angeli, Pascal Boeckx, Christophe Brumbt, Craig S. Cook, Maren Dubbert, Jens Dyckmans, Barbora Gallagher, Benjamin Gralher, Barbara Herbstritt, Pedro Hervé-Fernández, Christophe Hissler, Paul Koeniger, Arnaud Legout, Chandelle Joan Macdonald, Carlos Oyarzún, Regine Redelstein, Christof Seidler, Rolf Siegwolf, Christine Stumpp, Simon Thomsen, Markus Weiler, Christiane Werner, and Jeffrey J. McDonnell
Hydrol. Earth Syst. Sci., 22, 3619–3637, https://doi.org/10.5194/hess-22-3619-2018, https://doi.org/10.5194/hess-22-3619-2018, 2018
Short summary
Short summary
To extract water from soils for isotopic analysis, cryogenic water extraction is the most widely used removal technique. This work presents results from a worldwide laboratory intercomparison test of cryogenic extraction systems. Our results showed large differences in retrieved isotopic signatures among participating laboratories linked to interactions between soil type and properties, system setup, extraction efficiency, extraction system leaks, and each lab’s internal accuracy.
Ashley R. Pales, Biting Li, Heather M. Clifford, Shyla Kupis, Nimisha Edayilam, Dawn Montgomery, Wei-zhen Liang, Mine Dogan, Nishanth Tharayil, Nicole Martinez, Stephen Moysey, Brian Powell, and Christophe J. G. Darnault
Hydrol. Earth Syst. Sci., 22, 2487–2509, https://doi.org/10.5194/hess-22-2487-2018, https://doi.org/10.5194/hess-22-2487-2018, 2018
Arnaud Watlet, Olivier Kaufmann, Antoine Triantafyllou, Amaël Poulain, Jonathan E. Chambers, Philip I. Meldrum, Paul B. Wilkinson, Vincent Hallet, Yves Quinif, Michel Van Ruymbeke, and Michel Van Camp
Hydrol. Earth Syst. Sci., 22, 1563–1592, https://doi.org/10.5194/hess-22-1563-2018, https://doi.org/10.5194/hess-22-1563-2018, 2018
Short summary
Short summary
Understanding water infiltration in karst regions is crucial as the aquifers they host provide drinkable water for a quarter of the world's population. We present a non-invasive tool to image hydrological processes in karst systems. At our field site, the injection of electrical current in the ground, repeated daily over a 3-year period, allowed imaging changes in the groundwater content. We show that specific geological layers control seasonal to rainfall-triggered water infiltration dynamics.
Giovanna Dragonetti, Alessandro Comegna, Ali Ajeel, Gian Piero Deidda, Nicola Lamaddalena, Giuseppe Rodriguez, Giulio Vignoli, and Antonio Coppola
Hydrol. Earth Syst. Sci., 22, 1509–1523, https://doi.org/10.5194/hess-22-1509-2018, https://doi.org/10.5194/hess-22-1509-2018, 2018
Short summary
Short summary
The paper aims to infer the bulk electrical conductivity distribution in the root zone from EMI readings. TDR measurements were used as ground-truth data to evaluate the goodness of the estimations by EMI inversion. The approach is based on the mean and standard deviation of the EMI and TDR series. It looks for the physical reasons for the differences between EMI- and TDR-based electrical conductivity and provides a correction of the bias based on the statistical sources of the discrepancies.
David McJannet, Aaron Hawdon, Brett Baker, Luigi Renzullo, and Ross Searle
Hydrol. Earth Syst. Sci., 21, 6049–6067, https://doi.org/10.5194/hess-21-6049-2017, https://doi.org/10.5194/hess-21-6049-2017, 2017
Short summary
Short summary
Satellite and broad-scale model estimates of soil moisture have improved in resolution. However, validation and calibration of these products has been limited because of a lack of observations on corresponding scales. We use a mobile soil moisture monitoring platform, known as the
rover, to derive soil moisture at 9 km and 1 km resolution. We describe methods to calculate soil moisture and present results from multiple surveys. The products produced are well suited to validation studies.
Xicai Pan, Warren Helgason, Andrew Ireson, and Howard Wheater
Hydrol. Earth Syst. Sci., 21, 5401–5413, https://doi.org/10.5194/hess-21-5401-2017, https://doi.org/10.5194/hess-21-5401-2017, 2017
Short summary
Short summary
In this paper we present a case study from a heterogeneous pasture site in the Canadian prairies, where we have quantified the various components of the water balance on the field scale, and critically examine some of the simplifying assumptions which are often invoked when applying water budget approaches in applied hydrology. We highlight challenges caused by lateral fluxes of blowing snow and ambiguous partitioning of snow melt water into runoff and infiltration.
Martin Schrön, Markus Köhli, Lena Scheiffele, Joost Iwema, Heye R. Bogena, Ling Lv, Edoardo Martini, Gabriele Baroni, Rafael Rosolem, Jannis Weimar, Juliane Mai, Matthias Cuntz, Corinna Rebmann, Sascha E. Oswald, Peter Dietrich, Ulrich Schmidt, and Steffen Zacharias
Hydrol. Earth Syst. Sci., 21, 5009–5030, https://doi.org/10.5194/hess-21-5009-2017, https://doi.org/10.5194/hess-21-5009-2017, 2017
Short summary
Short summary
A field-scale average of near-surface water content can be sensed by cosmic-ray neutron detectors. To interpret, calibrate, and validate the integral signal, it is important to account for its sensitivity to heterogeneous patterns like dry or wet spots. We show how point samples contribute to the neutron signal based on their depth and distance from the detector. This approach robustly improves the sensor performance and data consistency, and even reveals otherwise hidden hydrological features.
Yiben Cheng, Hongbin Zhan, Wenbin Yang, Hongzhong Dang, and Wei Li
Hydrol. Earth Syst. Sci., 21, 5031–5042, https://doi.org/10.5194/hess-21-5031-2017, https://doi.org/10.5194/hess-21-5031-2017, 2017
Short summary
Short summary
This study uses a newly designed lysimeter to study three consecutive years (2013–2015) of deep soil recharge (DSR) underneath bare sand land on the eastern margin of Mu Us Sandy Land in the Ordos Basin of China. The objective is to identify the characteristics of the DSR distribution and the factors affecting the DSR distribution. Specifically, we would like to examine if the commonly used recharge coefficient concept can be applied for arid and semi-arid regions.
Ofer Dahan, Idan Katz, Lior Avishai, and Zeev Ronen
Hydrol. Earth Syst. Sci., 21, 4011–4020, https://doi.org/10.5194/hess-21-4011-2017, https://doi.org/10.5194/hess-21-4011-2017, 2017
Short summary
Short summary
In situ bioremediation of a perchlorate-contaminated vadose zone was conducted through infiltration of electron-donor-enriched water. A vadose zone monitoring system (VMS) provided real-time tracking of the hydraulic and chemical conditions across the unsaturated zone. Variations in concentration profiles of perchlorate, chloride, DOC and bromide in the vadose zone pore water showed limited migration capacity of biologically consumable carbon and significant mobilization of perchlorate.
Cécile Pellet and Christian Hauck
Hydrol. Earth Syst. Sci., 21, 3199–3220, https://doi.org/10.5194/hess-21-3199-2017, https://doi.org/10.5194/hess-21-3199-2017, 2017
Short summary
Short summary
This paper presents a detailed description of the new Swiss soil moisture monitoring network SOMOMOUNT, which comprises six stations distributed along an elevation gradient ranging from 1205 to 3410 m. The liquid soil moisture (LSM) data collected during the first 3 years are discussed with regard to their soil type and climate dependency as well as their altitudinal distribution. The elevation dependency of the LSM was found to be non-linear with distinct dynamics at high and low elevation.
Simon Matthias Kleinknecht, Holger Class, and Jürgen Braun
Hydrol. Earth Syst. Sci., 21, 1381–1396, https://doi.org/10.5194/hess-21-1381-2017, https://doi.org/10.5194/hess-21-1381-2017, 2017
Short summary
Short summary
Retardation of migrating contaminant vapors in the subsurface may mitigate groundwater contamination or vapor intrusion into buildings. An experimental investigation was conducted to quantify the retardation of carbon disulfide (CS2) vapor in moist porous media based on the analysis of concentration breakthrough curves. Findings linked retardation to types of porous media and water saturation. Moreover, the first evidence of biodegradation of the CS2 vapor was found in the column experiments.
Edoardo Martini, Ulrike Werban, Steffen Zacharias, Marco Pohle, Peter Dietrich, and Ute Wollschläger
Hydrol. Earth Syst. Sci., 21, 495–513, https://doi.org/10.5194/hess-21-495-2017, https://doi.org/10.5194/hess-21-495-2017, 2017
Short summary
Short summary
With a process-based interpretation of electromagnetic induction measurements, we discussed the potential and limitations of such a method for soil moisture mapping. Results will help clarify the complex and time-varying effect of stable soil properties and dynamic state variables on the physical parameters measured, with implications for future studies. We highlighted the importance of time-series data and the need for a multidisciplinary approach for proper interpretation.
Carol V. Tadros, Pauline C. Treble, Andy Baker, Ian Fairchild, Stuart Hankin, Regina Roach, Monika Markowska, and Janece McDonald
Hydrol. Earth Syst. Sci., 20, 4625–4640, https://doi.org/10.5194/hess-20-4625-2016, https://doi.org/10.5194/hess-20-4625-2016, 2016
Short summary
Short summary
We investigated the potential use of trace element and stable oxygen-isotope variations in cave drip water as palaeorainfall proxies in an Australian alpine karst site. Using 7 years of cave monitoring data, we constrained the hydrological processes impacting the drip-water composition and identified a robust ENSO–drip water hydrochemical relationship. These findings are fundamental for reconstructing past ENSO variability from speleothems (cave deposits) regionally and globally.
William Alexander Avery, Catherine Finkenbiner, Trenton E. Franz, Tiejun Wang, Anthony L. Nguy-Robertson, Andrew Suyker, Timothy Arkebauer, and Francisco Muñoz-Arriola
Hydrol. Earth Syst. Sci., 20, 3859–3872, https://doi.org/10.5194/hess-20-3859-2016, https://doi.org/10.5194/hess-20-3859-2016, 2016
Short summary
Short summary
Here we present a strategy to use globally available datasets in the calibration function used to convert observed moderated neutron counts into volumetric soil water content. While local sampling protocols are well documented for fixed probes, the use of roving probes presents new calibration challenges. With over 200 fixed probes and 10 roving probes in use globally, we anticipate this paper will serve as a keystone for the growing cosmic-ray neutron probe and hydrologic community.
Tuvia Turkeltaub, Daniel Kurtzman, and Ofer Dahan
Hydrol. Earth Syst. Sci., 20, 3099–3108, https://doi.org/10.5194/hess-20-3099-2016, https://doi.org/10.5194/hess-20-3099-2016, 2016
Short summary
Short summary
Efficient groundwater protection from pollution originating in agriculture requires effective monitoring means capable of tacking pollution processes in the vadose zone, long before groundwater pollution turns into an unavoidable fact. In this study, a vadose zone monitoring system that was installed under a crop field fertilized by dairy slurry enabled real-time tracking of nitrate plum migration down the vadose zone from the land surface to the water table at 18m depth.
Andre Peters, Thomas Nehls, and Gerd Wessolek
Hydrol. Earth Syst. Sci., 20, 2309–2315, https://doi.org/10.5194/hess-20-2309-2016, https://doi.org/10.5194/hess-20-2309-2016, 2016
Short summary
Short summary
The AWAT (Adaptive Window and Adaptive Threshold) filter routine for high-resolution lysimeter data is improved. The threshold scheme with original step interpolation yields unrealistic fluxes for high temporal resolution. Improvement applies linear and spline interpolation schemes so that fluxes in high temporal resolution are automatically calculated. The spline scheme allows continuous differentiability of filtered data so that any output resolution for the fluxes is sound.
Amber M. Peterson, Warren D. Helgason, and Andrew M. Ireson
Hydrol. Earth Syst. Sci., 20, 1373–1385, https://doi.org/10.5194/hess-20-1373-2016, https://doi.org/10.5194/hess-20-1373-2016, 2016
Short summary
Short summary
Remote sensing techniques can provide useful large-scale estimates of soil moisture. However, these methods often only sense near-surface soil moisture, whereas many applications require estimates of the entire root zone. In this study we propose and test methods to "depth-scale" the shallow soil moisture measurements obtained using the cosmic-ray neutron probe to represent the entire root zone, thereby improving the applicability of this measurement approach.
Cited articles
Abramova, M. M.: Movement of moisture as a liquid and vapor in soils of
semi-deserts, Internat. Assoc. Sci. Hydrol., Proc. Wageningen Symposium, 83, 781–789, 1969.
Aemisegger, F., Sturm, P., Graf, P., Sodemann, H., Pfahl, S., Knohl, A., and
Wernli, H.: Measuring variations of δ18O and δ2H in atmospheric water vapour
using two commercial laser-based spectrometers: an instrument
characterisation study, Atmos. Meas. Tech., 5, 1491–1511,
https://doi.org/10.5194/amt-5-1491-2012, 2012.
Agam, N. and Berliner, P. R.: Dew formation and water vapor adsorption in
semi-arid environments – A review, J. Arid Environ., 4,
572–590, https://doi.org/10.1016/j.jaridenv.2005.09.004, 2006.
Allison, G. B. and Hughes, M. W.: The use of natural tracers as indicators
of soil-water movement in a temperate semi-arid region, J. Hydrol., 60, 157–173, 1983.
Allison G. B., Barnes, C. J., Hughes M. W., and Leaney, F. W.: Effect of
climate and vegetation on oxygen-18 and deuterium profiles in soils, Int.
Symp. Iso. Hydrol. Water Resour. Dev., Vienna, Austria, 105–123, 1984.
Allison G. B., Barnes, C. J., and Hughes M. W.: Estimation of evaporation from the
normally “dry” lake frome in south Australia, J. Hydrol., 78,
229–242, 1985.
Allison, G. B., Colin-Kaczala A. F., and Fontes C. J.: Measurement of
Isotopic Equilibrium between Water, Water Vapor and Soil CO2 in Arid Zone
Soils, J. Hydrol., 95, 131–141, 1987.
Allison, G. B., Gee, G., and and Tyler, S. W.: Vadose-Zone Techniques for
Estimating Groundwater recharge in Arid and Semiarid Regions, Soil Sci. Soc.
Am. J., 58, 6–14, 1994.
Altuhafi, F., O'Sullivan, C., and Cavarretta, I.: Analysis of an Image-Based
Method to Quantify the Size and Shape of Sand Particles, J. Geotech.
Geoenviron., 139, 1290–1307,
https://doi.org/10.1061/(ASCE)GT.1943-5606.0000855, 2013.
Barnes, C. J. and Allison, G. B.: Tracing of Water Movement in the
unsaturated zone using stable isotopes of hydrogen and oxygen, J. Hydrol., 100, 143–176, 1988.
Barwick, V. and Prichard, E.: Terminology in Analytical Measurement:
Introduction to VIM 3, Eurachem, available at: www.eurachem.org (17 Febraury 2016) 2011.
Beyer, M., Gaj, M., Hamutoko, J., Koeniger, P., Wanke, H., and Himmelsbach,
T.: Estimation of groundwater recharge via deuterium labelling in the
semi-arid Cuvelai-Etosha Basin, Namibia, Isot. Environ. Health S., 51, 533–552, https://doi.org/10.1080/10256016.2015.1076407, 2015.
Braud, I., Bariac, T., Vauclin, M., Boujamlaoui, Z., Gaudet, J. P., Biron,
P., and Richard, P.: SiSPAT-Isotope, a coupled heat, water and stable
isotope (HDO and H218O) transport model for bare soil. Part II.
Evaluation and sensitivity tests using two laboratory data sets, J. Hydrol., 309, 301–320, https://doi.org/10.1016/j.jhydrol.2004.12.012, 2005.
Braud, I., Bariac, T., Biron, P., and Vauclin, M.: Isotopic composition of
bare soil evaporated water vapor. Part II: Modeling of RUBIC IV experimental
results, J. Hydrol., 369, 17–29,
https://doi.org/10.1016/j.jhydrol.2009.01.038, 2009.
Caldwell, M. M., Dawson, T. E., and Richards, J. H.: Hydraulic lift:
consequences of water efflux from the roots of plants, Oecologia, 113,
151–161, https://doi.org/10.1007/s004420050363, 1998.
Christelis, G., Struckmeier, W., Bäumle, R., and Bethune, S.: Groundwater in
Namibia: An explanation to the hydrogeological map, 1st ed, Dept. of Water
Affairs, Division Geohydrology; Geologigal Survey of Namibia; Namibia Water
Corporation; Federal Institute for Geosciences and Mineral Resources,
Windhoek, Namibia, Hannover, Germany, 128 pp., ISBN-No.:0-86976-571-X, 2001.
Clark, I. D. and Fritz, P.: Environmental Isotopes in Hydrogeology, Lewis
Publishers, Boca Raton, FL, USA, 328 pp., 1997.
Coplen, T., Herczeg, A., and Barnes, C.: Isotope Engineering – Using Stable
Isotopes of the Water Molecule to Solve Practical Problems, in:
Environmental Tracers in Subsurface Hydrology, Springer, New York, USA, 79–110, https://doi.org/10.1007/978-1-4615-4557-6_3, 2000.
Coplen, T. B.: Guidelines and recommended terms for expression of
stable-isotope-ratio and gas-ratio measurement results, Rapid Commun. Mass Sp., 25, 2538–2560, https://doi.org/10.1002/rcm.5129, 2011.
Craig, H.: Isotopic Variations in Meteoric Waters, Science, 133, 1702–1703, 1961.
Craig, H. and Gordon, L. I.: Deuterium and oxygen 18 variations in the
ocean and marine atmosphere. In proc. Stable Isotopes in Oceanographic
Studies and Paleotemperatures, 1965, Spoleto, Italy, edited by: E. Tongiogi, 9–130, V. Lishi e F., Pisa, Italy, 1965.
Dawson, T. E.: Hydraulic lift and water use by plants: implications for
water balance, performance and plant-plant interactions, Oecologia, 95,
565–574, 1993.
Dawson, T. E.: Determining water use by trees and forests from isotopic,
energy balance and transpiration analyses: the roles of tree size and
hydraulic lift, Tree Physiol., 16, 263–272, 1996.
Dawson, T. E. and Ehleringer, J. R.: Streamside trees that do not use stream
water, Nature, 350, 335–337, 1991.
Dawson, T. E., Mambelli, S., Plamboeck, A. H., Templer, P. H., and Tu, K.
P.: Stable Isotopes in Plant Ecology, Annu. Rev. Ecol. Syst., 33,
507–559, https://doi.org/10.1146/annurev.ecolsys.33.020602.095451, 2002.
Dincer, T., Al-Mugrin, A., and Zimmermann, U.: Study of the infiltration and
recharge through the sand dunes in arid zones with special reference to the
stable isotopes and thermonuclear tritium, J. Hydrol., 23,
79–109, https://doi.org/10.1016/0022-1694(74)90025-0, 1974.
Dragnich, P. A., Dungca, A. C., Pedleton Noah, L., and Tracy, A. R.: The
Cuvelai-Etosha Basin Management Approach; Assessing water resources
management in the Iishana sub-basin, Worchester Polytechnic Institute, Desert Research Foundation, Nambia, 2004.
Dubbert, M., Cuntz, M. M., Piayda, A., Maguàs, and Werner, C.: Partitioning
evapotranspiration – Testing the Craig and Gordon model with field
measurements of oxygen isotope ratios of evaporative fluxes, J. Hydrol., 496, 142–153,
https://doi.org/10.1016/j.jhydrol.2013.05.033, 2013.
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.
Fontes, J., Yousfi, M., and Allison, G. B.: Estimation of long-term, diffuse
groundwater discharge in the northern Sahara using stable isotope profiles
in soil water, J. Hydrol., 86, 315–327, 1986.
Garvelmann, J., Külls, C., and Weiler, M.: A porewater-based stable isotope
approach for the investigation of subsurface hydrological processes, Hydrol.
Earth Syst. Sci., 16, 631–640, https://doi.org/10.5194/hess-16-631-2012, 2012.
Gazis, C. and Feng, X.: A stable isotope study of soil water: evidence for
mixing and preferential flow paths, Geoderma, 119, 97–111,
https://doi.org/10.1016/S0016-7061(03)00243-X, 2004.
Hendry, M. J., Schmeling, E., Wassenaar, L. I., Barbour, S. L., and Pratt,
D.: Determining the stable isotope composition of pore water from saturated
and unsaturated zone core: improvements to the direct vapour equilibration
laser spectrometry method, Hydrol. Earth Syst. Sci., 19, 4427–4440,
https://doi.org/10.5194/hess-19-4427-2015, 2015.
Henschel, J. R. and Seely, M. K.: Ecophysiology of atmosspheric moisture in
the Namib Desert., Atmos. Res., 87, 362–368,
https://doi.org/10.1016/j.atmosres.2007.11.015, 2008.
Herczeg, A. L. and Leaney, F. W.: Review: environmental tracers in
arid-zone hydrology, Hydrogeol. J., 19, 17–29, 2011.
Kelln, C., Wassenaar L. I., and Hendry, M. J.: Stable Isotopes (δ18O, δ2H) of Pore Waters in Clay-Rich Aquitards: A
Comparison and Evaluation of Measurement Techniques, Ground Water Monit. R., 21, 108–116, 2001.
Kendall, C. and McDonnell, J. J.: Isotopes in catchment hydrology, Elsevier, New York, USA,
2012.
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.
Koeniger, P., Gaj, M., Beyer, M., and Himmelsbach, T.: Review on soil water
isotope based groundwater recharge estimations, Hydrol. Process.,
https://doi.org/10.1002/hyp.10775, accepted, 2016.
Lindenmaier, F. and Christelis, G.: Groundwater for the North of
Namibia: Summary Report of Activities of Phase I, Exploration of Ohangwena
II Aquifer and Preliminary Isotope Study, Volume 1a, Windhoek, Namibia, 2012.
Lindenmaier, F., Lohe C., and Quinger M.: Groundwater for the North of
Namibia: Executive Summary Phase I, Windhoek, Namibia, 2014.
Lee, K. S., Kim, J. M., Lee, D.-R., Kim, Y., and Lee, D.: Analysis of water
movement through an unsaturated soil zone in Jeju Island, Korea using stable
oxygen and hydrogen isotopes, J. Hydrol., 345, 199–211,
https://doi.org/10.1016/j.jhydrol.2007.08.006, 2007.
Mendelsohn, J., Jarvis A., Robertson T., Mendelsohn, J., Jarvis, A., and
Robertson, T.: A Profile and Atlas of the Cuvelai – Etosha Basin, RAISON;
Gondwana Collection, Windhoek, Namibia, 172–170, 2013.
Merlivat, L.: Molecular diffusivities of H216O, HD16O, and H218O in gases,
J. Chem. Phys., 69, 2864–2871, https://doi.org/10.1063/1.436884, 1978.
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.
Oerter, E., Finstad, K., Schaefer, J., Goldsmith, G. R., Dawson, T., and
Amundson, R.:
Oxygen isotope fractionation effects in soil water via interaction with
cations (Mg, Ca, K, Na) adsorbed to phyllosilicate clay minerals, J. Hydrol., 515, 1–9, 2014
Or, D., Lehmann, P., Shahraeeni, E., and Shokri, N.: Advances in
soil evaporation physics – A review, Vadose Zone J., 12, https://doi.org/10.2136/vzj2012.0163, 2013.
Orlowski, N., Frede, H.-G., Brüggemann, N., and Breuer, L.: Validation and
application of a cryogenic vacuum extraction system for soil and plant water
extraction for isotope analysis, J. Sens. Sens. Syst., 2, 179–193,
https://doi.org/10.5194/jsss-2-179-2013, 2013.
Rambo, J., Lai, C.-T., and Farlin, J.: On-Site Calibration for High Precision
Measurements of Water Vapor Isotope Ratios Using Off-Axis Cavity-Enhanced
Absorbtion Spectroscopy, J. Atmos. Ocean. Tech., 28,
1448–1457, 2011.
Richard, P. and Shoemaker, C. A.: A Comparison of Chemical and Isotopic
Hydrograph Separation, Water Resour. Res., 22, 1444–1454, 1986.
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.
Rothfuss, Y., Merz, S., Vanderborght, J., Hermes, N., Weuthen, A., Pohlmeier,
A., Vereecken, H., and Brüggemann, N.: Long-term and high-frequency
non-destructive monitoring of water stable isotope profiles in an evaporating
soil column, Hydrol. Earth Syst. Sci., 19, 4067–4080,
https://doi.org/10.5194/hess-19-4067-2015, 2015.
Savinand, S. M. and Epstein, S.: The oxygen and hydrogen isotope geochemistry of
clay minerals, Geochim. Cosmochim. Ac., 34, 25–42,
https://doi.org/10.1016/0016-7037(70)90149-3, 1970.
Saxena, R. K.: Oxygen-18 fractionation in nature and estimation of
groundwater recharge, Uppsala University, Department of Physical Geography,
Division of Hydrology, Sweden, 1987.
Scanlon, B. R., Healy, R. W., and Cook, P. G.: Choosing appropriate
techniques for quantifying groundwater recharge, Hydrogeol. J., 10, 18–39, https://doi.org/10.1007/s10040-001-0176-2, 2002.
Schack-Kirchner, H., Hildebrand, E. E., and von Wilpert, K.: Ein
konvektionsfreies Sammelsystem für Bodenluft, Z. Pflanz. Bodenkunde., 156, 307–310, 1993.
Singleton, M. J., Sonnenthal, E. L, Conrad, M. E., DePaolo, D., and Gee, G.
W.: Multiphase Reactive Transport Modeling of Seasonal Infiltration Events
and Stable Isotope Fractionation in Unsaturated Zone Pore Water and Vapor at
the Hanford Site, Vadose Zone J., 3, 775–785, 2004.
Sklash, M. G. and Farvolden, R. N.: The role of groundwater in storm
runoff., J. Hydrol., 43, 45–65, 1979.
Skrzypek, G., Mydłowski, A., Dogramaci, S., Hedley, P., Gibson, J. J.,
and Grierson, P. F.: Estimation of evaporative loss based on the
stable isotope composition of water using Hydrocalculator, J. Hydrol., 523, 781–789,
2015.
Soderberg, K., Good, S. P., Wang, L., and Caylor, K.: Stable Isotopes of
Water Vapor in the Vadose Zone: A Review of Measurement and Modeling
Techniques, Vadose Zone J., 11, 14 pp., https://doi.org/10.2136/vzj2011.0165, 2012.
Sutanto, S. J., van den Hurk, B., Dirmeyer, P. A., Seneviratne, S. I.,
Röckmann, T., Trenberth, K. E., Blyth, E. M., Wenninger, J., and Hoffmann,
G.: HESS Opinions “A perspective on isotope versus non-isotope approaches to
determine the contribution of transpiration to total evaporation”, Hydrol.
Earth Syst. Sci., 18, 2815–2827, https://doi.org/10.5194/hess-18-2815-2014, 2014.
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.
Stumpp, C. and Maloszewski, P.: Quantification of preferential flow and flow
heterogeneities in an unsaturated soil planted with different crops using
the environmental isotope δ18O, J. Hydrol., 394, 407–415, https://doi.org/10.1016/j.jhydrol.2010.09.014, 2010.
Sturm, P. and Knohl, A.: Water vapor δ2H and δ18O measurements using off-axis
integrated cavity output spectroscopy, Atmos. Meas. Tech., 3, 67–77,
https://doi.org/10.5194/amt-3-67-2010, 2010.
Tetzlaff, D., Soulsby, C., Waldron, S., Malcolm, I. A., Bacon, P. J., Dunn,
S. M., Lilly, A., and Youngson, A. F.: Conceptualization of runoff processes
using a geographical information system and tracers in a nested mesoscale
catchment, Hydrol. Process., 21, 1289–1307, https://doi.org/10.1002/hyp.6309,
2007.
VanDeVelde, J. H. and Bowen, G. J.: Effects of chemical pretreatments on the
hydrogen isotope composition of 2:1 clay minerals, Rapid Commun. Mass. Sp., 27, 1143–1148, https://doi.org/10.1002/rcm.6554, 2013.
van Geldern, R. and Barth, J. A.: Optimization of instrument setup and
post-run corrections for oxygen and hydrogen stable isotope measurements of
water by isotope ratio infrared spectroscopy (IRIS), Limnol. Oceangr.-Meth., 10, 1024–1036, https://doi.org/10.4319/lom.2012.10.1024, 2012.
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.
Walker, G. R., Woods, P. H., and Allison, G. B.: Interlaboratory comparison
of methods to determine the stable isotope composition of soil water,
Chem. Geol., 111, 297–306, https://doi.org/10.1016/0009-2541(94)90096-5,
1994.
Wang, L., Caylor, K., and Dragoni, D.: On the calibration of continuous,
high-precision δ18O and δ2H measurements using an off-axis
integrated cavity output spectrometer, Rapid Commun. Mass Sp. 23, 530–536, 2009.
Wang, L., Good, S. P., Caylor, K. K., and Cernusak, L. A.: Direct
quantification of leaf transpiration isotopic composition, Agr. Forest Meteorol., 154-155, 127–135, https://doi.org/10.1016/j.agrformet.2011.10.018,
2012.
Wassenaar, L. I., Hendry, M. J., Chostner V.L., and Lis G. P.: High
Resolution Pore Water 2H and 18O Measurements by
H2O(liquid)H2O(vapor) Equilibration Laser Spectroscopy,
Environ. Sci. Technol., 42, 9262–9267, 2008.
West, A. G., Patrickson, S. J., Ehleringer, J. R.: Water extraction times for
plant and soil materials used in stable isotope analysis, Rapid Commun. Mass
Sp., 20, 1317–1321, 2006.
Western, A. W., Zhou, S.-L., Grayson, R. B., McMahon, T. A.,
Blöschl, G., and Wilson, D. J.: Spatial correlation of
soil moisture in small catchments and its relationship to dominant spatial
hydrological processes, J. Hydrol., 286, 113–134, https://doi.org/10.1016/j.jhydrol.2003.09.014,
2004.
Wilson G. W., Fredlund D. G., and Barbour S. L.: The effect of soil suction on
evaporative fluxes from soil surfaces., Can. Geotech. J., 34,
145–155, 1997.
Wu, Y., Zhou, H., Zheng, X.-J., Li, Y., and Tang, L.-S.: Seasonal changes in
the water use strategies of three co-occurring desert shrubs, Hydrol.
Process., 28, 6265–6275, https://doi.org/10.1002/hyp.10114, 2014.
Yang Q., Xiao, H., Zhao, L., Zhou, M., and Li, C., Coa, S.: Stable isotope
techniques in plant water sources: a review, Science in Cold and Arid
Regions, 2, 112–122, 2010.
Zimmermann, U., Münnich K.O., and Roether W.: Downward movement of soil
moisture traced by means of hydrogen isotopes, Geoph. Monog. Series, 11, 28–26, 1967.
