Articles | Volume 17, issue 3
https://doi.org/10.5194/hess-17-1003-2013
© Author(s) 2013. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Special issue:
https://doi.org/10.5194/hess-17-1003-2013
© Author(s) 2013. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Research article
| 
07 Mar 2013
Research article |
| 07 Mar 2013
Linking soil moisture balance and source-responsive models to estimate diffuse and preferential components of groundwater recharge
M. O. Cuthbert
Water Sciences Research Group, School of Geography, Earth and Environmental Sciences, University of Birmingham, Birmingham B15 2TT, UK
present address: Water Research Laboratory, School of Civil and Environmental Engineering, University of New South Wales, 110 King St, Manly Vale, NSW, 2093, Australia
R. Mackay
Geotechnical and Hydrogeological Engineering Research Group, Monash University, Churchill, Victoria, Australia
J. R. Nimmo
US Geological Survey, Menlo Park, California, USA
Related authors
Katie Coleborn, Gabriel C. Rau, Mark O. Cuthbert, Andy Baker, and Owen Navarre
Hydrol. Earth Syst. Sci., 20, 4439–4455, https://doi.org/10.5194/hess-20-4439-2016, https://doi.org/10.5194/hess-20-4439-2016, 2016
Short summary
Short summary
This is the first observation of tree water use in cave drip water. Our novel time series analysis using the synchrosqueeze transform identified daily and sub-daily oscillations in drip rate. The only hypothesis consistent with hydrologic theory and the data was that the oscillations were caused by solar driven pumping by trees above the cave. We propose a new protocol for inferring karst architecture and our findings support research on the impact trees on speleothem paleoclimate proxies.
R. A. Crane, M. O. Cuthbert, and W. Timms
Hydrol. Earth Syst. Sci., 19, 3991–4000, https://doi.org/10.5194/hess-19-3991-2015, https://doi.org/10.5194/hess-19-3991-2015, 2015
Short summary
Short summary
We present an interrupted-flow centrifugation technique to characterise the vertical hydraulic properties of dual porosity, low permeability media. Use of large core samples (100mm diameter) enables hydraulic-conductivity-scale issues in dual porosity media to be overcome. Elevated centrifugal force also enables simulating in situ total stress conditions. The methodology is an important tool to assess the ability of dual porosity aquitards to protect underlying aquifer systems.
Katie Coleborn, Gabriel C. Rau, Mark O. Cuthbert, Andy Baker, and Owen Navarre
Hydrol. Earth Syst. Sci., 20, 4439–4455, https://doi.org/10.5194/hess-20-4439-2016, https://doi.org/10.5194/hess-20-4439-2016, 2016
Short summary
Short summary
This is the first observation of tree water use in cave drip water. Our novel time series analysis using the synchrosqueeze transform identified daily and sub-daily oscillations in drip rate. The only hypothesis consistent with hydrologic theory and the data was that the oscillations were caused by solar driven pumping by trees above the cave. We propose a new protocol for inferring karst architecture and our findings support research on the impact trees on speleothem paleoclimate proxies.
R. A. Crane, M. O. Cuthbert, and W. Timms
Hydrol. Earth Syst. Sci., 19, 3991–4000, https://doi.org/10.5194/hess-19-3991-2015, https://doi.org/10.5194/hess-19-3991-2015, 2015
Short summary
Short summary
We present an interrupted-flow centrifugation technique to characterise the vertical hydraulic properties of dual porosity, low permeability media. Use of large core samples (100mm diameter) enables hydraulic-conductivity-scale issues in dual porosity media to be overcome. Elevated centrifugal force also enables simulating in situ total stress conditions. The methodology is an important tool to assess the ability of dual porosity aquitards to protect underlying aquifer systems.
Related subject area
Subject: Vadose Zone Hydrology | Techniques and Approaches: Modelling approaches
Effects of dynamic changes of desiccation cracks on preferential flow: experimental investigation and numerical modeling
Numerical assessment of morphological and hydraulic properties of moss, lichen and peat from a permafrost peatland
A robust upwind mixed hybrid finite element method for transport in variably saturated porous media
Soil-vegetation-water interactions controlling solute flow and transport in volcanic ash soils of the high Andes
Semi-continuum modelling of unsaturated porous media flow to explain the Bauters' paradox
From soil water monitoring data to vadose zone water fluxes: a comprehensive example of reverse hydrology
Stepping beyond perfectly mixed conditions in soil hydrological modelling using a Lagrangian approach
Using machine learning to predict optimal electromagnetic induction instrument configurations for characterizing the shallow subsurface
Gravity as a tool to improve the hydrologic mass budget in karstic areas
A scaling procedure for straightforward computation of sorptivity
From hydraulic root architecture models to macroscopic representations of root hydraulics in soil water flow and land surface models
Simulated or measured soil moisture: which one is adding more value to regional landslide early warning?
Interaction of soil water and groundwater during the freezing–thawing cycle: field observations and numerical modeling
Assessing the dynamics of soil salinity with time-lapse inversion of electromagnetic data guided by hydrological modelling
Simulation of reactive solute transport in the critical zone: a Lagrangian model for transient flow and preferential transport
Investigating the impact of exit effects on solute transport in macroporous media
Comparison of root water uptake models in simulating CO2 and H2O fluxes and growth of wheat
Understanding the mass, momentum, and energy transfer in the frozen soil with three levels of model complexities
A field-validated surrogate crop model for predicting root-zone moisture and salt content in regions with shallow groundwater
Characterizing uncertainty in the hydraulic parameters of oil sands mine reclamation covers and its influence on water balance predictions
Simulating preferential soil water flow and tracer transport using the Lagrangian Soil Water and Solute Transport Model
Assessment of simulated soil moisture from WRF Noah, Noah-MP, and CLM land surface schemes for landslide hazard application
Efficient estimation of effective hydraulic properties of stratal undulating surface layer using time-lapse multi-channel GPR
Partitioning snowmelt and rainfall in the critical zone: effects of climate type and soil properties
A unique vadose zone model for shallow aquifers: the Hetao irrigation district, China
Modelling of shallow water table dynamics using conceptual and physically based integrated surface-water–groundwater hydrologic models
Capturing soil-water and groundwater interactions with an iterative feedback coupling scheme: new HYDRUS package for MODFLOW
Caffeine vs. carbamazepine as indicators of wastewater pollution in a karst aquifer
Predicting the soil water retention curve from the particle size distribution based on a pore space geometry containing slit-shaped spaces
Technical note: Saturated hydraulic conductivity and textural heterogeneity of soils
Water ages in the critical zone of long-term experimental sites in northern latitudes
Ecohydrological particle model based on representative domains
Impact of capillary rise and recirculation on simulated crop yields
Soil hydraulic material properties and layered architecture from time-lapse GPR
Root growth, water uptake, and sap flow of winter wheat in response to different soil water conditions
Using lagged dependence to identify (de)coupled surface and subsurface soil moisture values
Shallow water table effects on water, sediment, and pesticide transport in vegetative filter strips – Part 1: nonuniform infiltration and soil water redistribution
Shallow water table effects on water, sediment, and pesticide transport in vegetative filter strips – Part 2: model coupling, application, factor importance, and uncertainty
A pore-size classification for peat bogs derived from unsaturated hydraulic properties
Monitoring and modeling infiltration–recharge dynamics of managed aquifer recharge with desalinated seawater
Effect of unrepresented model errors on estimated soil hydraulic material properties
Saturated hydraulic conductivity model computed from bimodal water retention curves for a range of New Zealand soils
Ross scheme, Newton–Raphson iterative methods and time-stepping strategies for solving the mixed form of Richards' equation
Feasibility analysis of using inverse modeling for estimating field-scale evapotranspiration in maize and soybean fields from soil water content monitoring networks
A case study of field-scale maize irrigation patterns in western Nebraska: implications for water managers and recommendations for hyper-resolution land surface modeling
Benchmarking test of empirical root water uptake models
iCRESTRIGRS: a coupled modeling system for cascading flood–landslide disaster forecasting
EnKF with closed-eye period – towards a consistent aggregation of information in soil hydrology
Prediction of biopore- and matrix-dominated flow from X-ray CT-derived macropore network characteristics
A Lagrangian model for soil water dynamics during rainfall-driven conditions
Yi Luo, Jiaming Zhang, Zhi Zhou, Juan P. Aguilar-Lopez, Roberto Greco, and Thom Bogaard
Hydrol. Earth Syst. Sci., 27, 783–808, https://doi.org/10.5194/hess-27-783-2023, https://doi.org/10.5194/hess-27-783-2023, 2023
Short summary
Short summary
This paper describes an experiment and modeling of the hydrological response of desiccation cracks under long-term wetting–drying cycles. We developed a new dynamic dual-permeability model to quantify the dynamic evolution of desiccation cracks and associated preferential flow and moisture distribution. Compared to other models, the dynamic dual-permeability model could describe the experimental data much better, but it also provided an improved description of the underlying physics.
Simon Cazaurang, Manuel Marcoux, Oleg S. Pokrovsky, Sergey V. Loiko, Artem G. Lim, Stéphane Audry, Liudmila S. Shirokova, and Laurent Orgogozo
Hydrol. Earth Syst. Sci., 27, 431–451, https://doi.org/10.5194/hess-27-431-2023, https://doi.org/10.5194/hess-27-431-2023, 2023
Short summary
Short summary
Moss, lichen and peat samples are reconstructed using X-ray tomography. Most samples can be cut down to a representative volume based on porosity. However, only homogeneous samples could be reduced to a representative volume based on hydraulic conductivity. For heterogeneous samples, a devoted pore network model is computed. The studied samples are mostly highly porous and water-conductive. These results must be put into perspective with compressibility phenomena occurring in field tests.
Anis Younes, Hussein Hoteit, Rainer Helmig, and Marwan Fahs
Hydrol. Earth Syst. Sci., 26, 5227–5239, https://doi.org/10.5194/hess-26-5227-2022, https://doi.org/10.5194/hess-26-5227-2022, 2022
Short summary
Short summary
Despite its advantages for the simulation of flow in heterogeneous and fractured porous media, the mixed hybrid finite element method has been rarely used for transport as it suffers from strong unphysical oscillations. We develop here a new upwind scheme for the mixed hybrid finite element that can avoid oscillations. Numerical examples confirm the robustness of this new scheme for the simulation of contaminant transport in both saturated and unsaturated conditions.
Sebastián Páez-Bimos, Armando Molina, Marlon Calispa, Pierre Delmelle, Braulio Lahuatte, Marcos Villacís, Teresa Muñoz, and Veerle Vanacker
Hydrol. Earth Syst. Sci. Discuss., https://doi.org/10.5194/hess-2022-294, https://doi.org/10.5194/hess-2022-294, 2022
Revised manuscript accepted for HESS
Short summary
Short summary
This study analyses how vegetation influences soil hydrology, water fluxes and chemical weathering rates in the high Andes. There are clear differences in the A horizon. The extent of soil chemical weathering varies depending on vegetation. This difference is attributed mainly to the water fluxes. Our findings reveal that vegetation can modify soil properties in the uppermost horizon altering the water balance, solutes, and chemical weathering throughout the entire soil profile.
Jakub Kmec, Miloslav Šír, Tomáš Fürst, and Rostislav Vodák
EGUsphere, https://doi.org/10.5194/egusphere-2022-673, https://doi.org/10.5194/egusphere-2022-673, 2022
Short summary
Short summary
When rain falls on the ground, most of the water subsequently flows through the soil. The movement of water through the partially wet soil layer is surprisingly complicated. For decades, no mathematical model has been able to capture this process in its entire complexity. Here, we present a model that aims to solve this long-standing problem. In this paper, we show that the model correctly reproduces the transition between diffusion and preferential flow regimes.
Marleen Ambrosia Schübl, Giuseppe Brunetti, Gabriele Fuchs, and Christine Stumpp
Hydrol. Earth Syst. Sci. Discuss., https://doi.org/10.5194/hess-2022-261, https://doi.org/10.5194/hess-2022-261, 2022
Revised manuscript accepted for HESS
Short summary
Short summary
Estimating groundwater recharge through the unsaturated zone is a difficult task and fundamentally associated with uncertainties. One of the few methods available is inverse modeling based on soil water measurements. In this study, we used a Nested Sampling algorithm within a Bayesian probabilistic framework to assess model uncertainties at 14 sites in Austria. Further, we analyzed simulated recharge rates to identify factors influencing groundwater recharge rates and their temporal variability.
Alexander Sternagel, Ralf Loritz, Brian Berkowitz, and Erwin Zehe
Hydrol. Earth Syst. Sci., 26, 1615–1629, https://doi.org/10.5194/hess-26-1615-2022, https://doi.org/10.5194/hess-26-1615-2022, 2022
Short summary
Short summary
We present a (physically based) Lagrangian approach to simulate diffusive mixing processes on the pore scale beyond perfectly mixed conditions. Results show the feasibility of the approach for reproducing measured mixing times and concentrations of isotopes over pore sizes and that typical shapes of breakthrough curves (normally associated with non-uniform transport in heterogeneous soils) may also occur as a result of imperfect subscale mixing in a macroscopically homogeneous soil matrix.
Kim Madsen van't Veen, Ty Paul Andrew Ferré, Bo Vangsø Iversen, and Christen Duus Børgesen
Hydrol. Earth Syst. Sci., 26, 55–70, https://doi.org/10.5194/hess-26-55-2022, https://doi.org/10.5194/hess-26-55-2022, 2022
Short summary
Short summary
Geophysical instruments are often used in hydrological surveys. A geophysical model that couples electrical conductivity in the subsurface layers with measurements from an electromagnetic induction instrument was combined with a machine learning algorithm. The study reveals that this combination can estimate the identifiability of electrical conductivity in a layered soil and provide insight into the best way to configure the instrument for a specific field site.
Tommaso Pivetta, Carla Braitenberg, Franci Gabrovšek, Gerald Gabriel, and Bruno Meurers
Hydrol. Earth Syst. Sci., 25, 6001–6021, https://doi.org/10.5194/hess-25-6001-2021, https://doi.org/10.5194/hess-25-6001-2021, 2021
Short summary
Short summary
Gravimetry offers a valid complement to classical hydrologic measurements in order to characterize karstic systems in which the recharge process causes fast accumulation of large water volumes in the voids of the epi-phreatic system. In this contribution we show an innovative integration of gravimetric and hydrologic observations to constrain a hydrodynamic model of the Škocjan Caves (Slovenia). We demonstrate how the inclusion of gravity observations improves the water mass budget estimates.
Laurent Lassabatere, Pierre-Emmanuel Peyneau, Deniz Yilmaz, Joseph Pollacco, Jesús Fernández-Gálvez, Borja Latorre, David Moret-Fernández, Simone Di Prima, Mehdi Rahmati, Ryan D. Stewart, Majdi Abou Najm, Claude Hammecker, and Rafael Angulo-Jaramillo
Hydrol. Earth Syst. Sci., 25, 5083–5104, https://doi.org/10.5194/hess-25-5083-2021, https://doi.org/10.5194/hess-25-5083-2021, 2021
Short summary
Short summary
Soil sorptivity is a crucial parameter for the modeling of water infiltration into soils. The standard equation used to compute sorptivity from the soil water retention curve, the unsaturated hydraulic conductivity, and initial and final water contents may lead to erroneous estimates due to its complexity. This study proposes a new straightforward scaling procedure for estimations of sorptivity for four famous and commonly used hydraulic models.
Jan Vanderborght, Valentin Couvreur, Felicien Meunier, Andrea Schnepf, Harry Vereecken, Martin Bouda, and Mathieu Javaux
Hydrol. Earth Syst. Sci., 25, 4835–4860, https://doi.org/10.5194/hess-25-4835-2021, https://doi.org/10.5194/hess-25-4835-2021, 2021
Short summary
Short summary
Root water uptake is an important process in the terrestrial water cycle. How this process depends on soil water content, root distributions, and root properties is a soil–root hydraulic problem. We compare different approaches to implementing root hydraulics in macroscopic soil water flow and land surface models.
Adrian Wicki, Per-Erik Jansson, Peter Lehmann, Christian Hauck, and Manfred Stähli
Hydrol. Earth Syst. Sci., 25, 4585–4610, https://doi.org/10.5194/hess-25-4585-2021, https://doi.org/10.5194/hess-25-4585-2021, 2021
Short summary
Short summary
Soil moisture information was shown to be valuable for landslide prediction. Soil moisture was simulated at 133 sites in Switzerland, and the temporal variability was compared to the regional occurrence of landslides. We found that simulated soil moisture is a good predictor for landslides, and that the forecast goodness is similar to using in situ measurements. This encourages the use of models for complementing existing soil moisture monitoring networks for regional landslide early warning.
Hong-Yu Xie, Xiao-Wei Jiang, Shu-Cong Tan, Li Wan, Xu-Sheng Wang, Si-Hai Liang, and Yijian Zeng
Hydrol. Earth Syst. Sci., 25, 4243–4257, https://doi.org/10.5194/hess-25-4243-2021, https://doi.org/10.5194/hess-25-4243-2021, 2021
Short summary
Short summary
Freezing-induced groundwater migration and water table decline are widely observed, but quantitative understanding of these processes is lacking. By considering wintertime atmospheric conditions and occurrence of lateral groundwater inflow, a model coupling soil water and groundwater reproduced field observations of soil temperature, soil water content, and groundwater level well. The model results led to a clear understanding of the balance of the water budget during the freezing–thawing cycle.
Mohammad Farzamian, Dario Autovino, Angelo Basile, Roberto De Mascellis, Giovanna Dragonetti, Fernando Monteiro Santos, Andrew Binley, and Antonio Coppola
Hydrol. Earth Syst. Sci., 25, 1509–1527, https://doi.org/10.5194/hess-25-1509-2021, https://doi.org/10.5194/hess-25-1509-2021, 2021
Short summary
Short summary
Soil salinity is a serious threat in numerous arid and semi-arid areas of the world. Given this threat, efficient field assessment methods are needed to monitor the dynamics of soil salinity in salt-affected lands efficiently. We demonstrate that rapid and non-invasive geophysical measurements modelled by advanced numerical analysis of the signals and coupled with hydrological modelling can provide valuable information to assess the spatio-temporal variability in soil salinity over large areas.
Alexander Sternagel, Ralf Loritz, Julian Klaus, Brian Berkowitz, and Erwin Zehe
Hydrol. Earth Syst. Sci., 25, 1483–1508, https://doi.org/10.5194/hess-25-1483-2021, https://doi.org/10.5194/hess-25-1483-2021, 2021
Short summary
Short summary
The key innovation of the study is a method to simulate reactive solute transport in the vadose zone within a Lagrangian framework. We extend the LAST-Model with a method to account for non-linear sorption and first-order degradation processes during unsaturated transport of reactive substances in the matrix and macropores. Model evaluations using bromide and pesticide data from irrigation experiments under different flow conditions on various timescales show the feasibility of the method.
Jérôme Raimbault, Pierre-Emmanuel Peyneau, Denis Courtier-Murias, Thomas Bigot, Jaime Gil Roca, Béatrice Béchet, and Laurent Lassabatère
Hydrol. Earth Syst. Sci., 25, 671–683, https://doi.org/10.5194/hess-25-671-2021, https://doi.org/10.5194/hess-25-671-2021, 2021
Short summary
Short summary
Contaminant transport in soils is known to be affected by soil heterogeneities such as macropores. The transport properties of heterogeneous porous media can be studied in laboratory columns. However, the results reported in this study (a combination of breakthrough experiments, magnetic resonance imaging and computer simulations of transport) show that these properties can be largely affected by the boundary devices of the columns, thus highlighting the need to take their effect into account.
Thuy Huu Nguyen, Matthias Langensiepen, Jan Vanderborght, Hubert Hüging, Cho Miltin Mboh, and Frank Ewert
Hydrol. Earth Syst. Sci., 24, 4943–4969, https://doi.org/10.5194/hess-24-4943-2020, https://doi.org/10.5194/hess-24-4943-2020, 2020
Short summary
Short summary
The mechanistic Couvreur root water uptake (RWU) model that is based on plant hydraulics and links root system properties to RWU, water stress, and crop development can evaluate the impact of certain crop properties on crop performance in different environments and soils, while the Feddes RWU approach does not possess such flexibility. This study also shows the importance of modeling root development and how it responds to water deficiency to predict the impact of water stress on crop growth.
Lianyu Yu, Yijian Zeng, and Zhongbo Su
Hydrol. Earth Syst. Sci., 24, 4813–4830, https://doi.org/10.5194/hess-24-4813-2020, https://doi.org/10.5194/hess-24-4813-2020, 2020
Short summary
Short summary
Soil mass and heat transfer processes were represented in three levels of model complexities to understand soil freeze–thaw mechanisms. Results indicate that coupled mass and heat transfer models considerably improved simulations of the soil hydrothermal regime. Vapor flow and thermal effects on water flow are the main mechanisms for the improvements. Given the explicit consideration of airflow, vapor flow and its effects on heat transfer were enhanced during the freeze–thaw transition period.
Zhongyi Liu, Zailin Huo, Chaozi Wang, Limin Zhang, Xianghao Wang, Guanhua Huang, Xu Xu, and Tammo Siert Steenhuis
Hydrol. Earth Syst. Sci., 24, 4213–4237, https://doi.org/10.5194/hess-24-4213-2020, https://doi.org/10.5194/hess-24-4213-2020, 2020
Short summary
Short summary
We have developed an integrated surrogate model for arid irrigated areas with shallow groundwater that links crop growth with soil water and salinity in the vadose zone. The model recognizes that field capacity is reached when the matric potential is equal to the height above the groundwater table. The model applies areas with shallow groundwater for which only very few surrogate models are available for most surface irrigation systems in the world without suffering from high groundwater.
M. Shahabul Alam, S. Lee Barbour, and Mingbin Huang
Hydrol. Earth Syst. Sci., 24, 735–759, https://doi.org/10.5194/hess-24-735-2020, https://doi.org/10.5194/hess-24-735-2020, 2020
Short summary
Short summary
This study quantifies uncertainties in the prediction of long-term water balance for mine reclamation soil covers using random sampling of model parameter distributions. Parameter distributions were obtained from model optimization for field monitoring data. Variability in climate is a greater source of uncertainty than the model parameters in evaporation predictions, while climate variability and model parameters exert similar uncertainty on predictions of net percolation.
Alexander Sternagel, Ralf Loritz, Wolfgang Wilcke, and Erwin Zehe
Hydrol. Earth Syst. Sci., 23, 4249–4267, https://doi.org/10.5194/hess-23-4249-2019, https://doi.org/10.5194/hess-23-4249-2019, 2019
Short summary
Short summary
We present our hydrological LAST-Model to simulate preferential soil water flow and tracer transport in macroporous soils. It relies on a Lagrangian perspective of the movement of discrete water particles carrying tracer masses through the subsoil and is hence an alternative approach to common models. Sensitivity analyses reveal the physical validity of the model concept and evaluation tests show that LAST can depict well observed tracer mass profiles with fingerprints of preferential flow.
Lu Zhuo, Qiang Dai, Dawei Han, Ningsheng Chen, and Binru Zhao
Hydrol. Earth Syst. Sci., 23, 4199–4218, https://doi.org/10.5194/hess-23-4199-2019, https://doi.org/10.5194/hess-23-4199-2019, 2019
Short summary
Short summary
This study assesses the usability of WRF model-simulated soil moisture for landslide monitoring in northern Italy. In particular, three advanced land surface model schemes (Noah, Noah-MP, and CLM4) are used to provide multi-layer soil moisture data. The results have shown Noah-MP can provide the best landslide monitoring performance. It is also demonstrated that a single soil moisture sensor located in plain area has a high correlation with a significant proportion of the study area.
Xicai Pan, Stefan Jaumann, Jiabao Zhang, and Kurt Roth
Hydrol. Earth Syst. Sci., 23, 3653–3663, https://doi.org/10.5194/hess-23-3653-2019, https://doi.org/10.5194/hess-23-3653-2019, 2019
Short summary
Short summary
This study suggests an efficient approach to obtain plot-scale soil hydraulic properties for the shallow structural soils via non-invasive ground-penetrating radar measurements. Facilitated by spatial information of lateral water flow, this approach is more efficient than the widely used inversion approaches relying on intensive soil moisture monitoring. The acquisition of such quantitative information is of great interest to fields such as hydrology and precision agriculture.
John C. Hammond, Adrian A. Harpold, Sydney Weiss, and Stephanie K. Kampf
Hydrol. Earth Syst. Sci., 23, 3553–3570, https://doi.org/10.5194/hess-23-3553-2019, https://doi.org/10.5194/hess-23-3553-2019, 2019
Short summary
Short summary
Streamflow in high-elevation and high-latitude areas may be vulnerable to snow loss, making it important to quantify how snowmelt and rainfall are divided between soil storage, drainage below plant roots, evapotranspiration and runoff. We examine this separation in different climates and soils using a physically based model. Results show runoff may be reduced with snowpack decline in all climates. The mechanisms responsible help explain recent observations of streamflow sensitivity to snow loss.
Zhongyi Liu, Xingwang Wang, Zailin Huo, and Tammo Siert Steenhuis
Hydrol. Earth Syst. Sci., 23, 3097–3115, https://doi.org/10.5194/hess-23-3097-2019, https://doi.org/10.5194/hess-23-3097-2019, 2019
Short summary
Short summary
A novel approach is taken in simulating the hydrology of the vadose zone in areas with shallow groundwater. The model recognizes that field capacity is reached when the matric potential is equal to the height above the groundwater table. The model can be used in areas with shallow groundwater to optimize irrigation water use and minimize tailwater losses.
Mohammad Bizhanimanzar, Robert Leconte, and Mathieu Nuth
Hydrol. Earth Syst. Sci., 23, 2245–2260, https://doi.org/10.5194/hess-23-2245-2019, https://doi.org/10.5194/hess-23-2245-2019, 2019
Short summary
Short summary
Modelling of shallow water table fluctuations is usually carried out using physically based numerical models. These models have notable limitations regarding intensive required data and computational burden. This paper presents an alternative modelling approach for modelling of such cases by introducing modifications to the calculation of groundwater recharge and saturated flow of a conceptual hydrologic model.
Jicai Zeng, Jinzhong Yang, Yuanyuan Zha, and Liangsheng Shi
Hydrol. Earth Syst. Sci., 23, 637–655, https://doi.org/10.5194/hess-23-637-2019, https://doi.org/10.5194/hess-23-637-2019, 2019
Short summary
Short summary
Accurately capturing the soil-water–groundwater interaction is vital for all disciplines related to subsurface flow but is difficult when undergoing significant nonlinearity in the modeling system. A new soil-water flow package is developed to solve the switching-form Richards’ equation. A multi-scale water balance analysis joins unsaturated–saturated models at separated scales. The whole system is solved efficiently with an iterative feedback coupling scheme.
Noam Zach Dvory, Yakov Livshitz, Michael Kuznetsov, Eilon Adar, Guy Gasser, Irena Pankratov, Ovadia Lev, and Alexander Yakirevich
Hydrol. Earth Syst. Sci., 22, 6371–6381, https://doi.org/10.5194/hess-22-6371-2018, https://doi.org/10.5194/hess-22-6371-2018, 2018
Short summary
Short summary
This research is paramount given the significance of karst aquifers as essential drinking water sources. While CBZ is considered conservative, CAF is subject to sorption and degradation, and therefore each of these two pollutants can be considered effective tracers for specific assessment of aquifer contamination. The model presented in this paper shows how each of the mentioned contaminants could serve as a better tool for aquifer contamination characterization and its treatment.
Chen-Chao Chang and Dong-Hui Cheng
Hydrol. Earth Syst. Sci., 22, 4621–4632, https://doi.org/10.5194/hess-22-4621-2018, https://doi.org/10.5194/hess-22-4621-2018, 2018
Short summary
Short summary
The soil water retention curve (SWRC) is fundamental to researching water flow and chemical transport in unsaturated media. However, the traditional prediction models underestimate the water content in the dry range of the SWRC. A method was therefore proposed to improve the estimation of the SWRC using a pore model containing slit-shaped spaces. The results show that the predicted SWRCs using the improved method reasonably approximated the measured SWRCs.
Carlos García-Gutiérrez, Yakov Pachepsky, and Miguel Ángel Martín
Hydrol. Earth Syst. Sci., 22, 3923–3932, https://doi.org/10.5194/hess-22-3923-2018, https://doi.org/10.5194/hess-22-3923-2018, 2018
Short summary
Short summary
Saturated hydraulic conductivity (Ksat) is an important soil parameter that highly depends on soil's particle size distribution (PSD). The nature of this dependency is explored in this work in two ways, (1) by using the information entropy as a heterogeneity parameter of the PSD and (2) by using descriptions of PSD in forms of textural triplets, different than the usual description in terms of the triplet of sand, silt, and clay contents.
Matthias Sprenger, Doerthe Tetzlaff, Jim Buttle, Hjalmar Laudon, and Chris Soulsby
Hydrol. Earth Syst. Sci., 22, 3965–3981, https://doi.org/10.5194/hess-22-3965-2018, https://doi.org/10.5194/hess-22-3965-2018, 2018
Short summary
Short summary
We estimated water ages in the upper critical zone with a soil physical model (SWIS) and found that the age of water stored in the soil, as well as of water leaving the soil via evaporation, transpiration, or recharge, was younger the higher soil water storage (inverse storage effect). Travel times of transpiration and evaporation were different. We conceptualized the subsurface into fast and slow flow domains and the water was usually half as young in the fast as in the slow flow domain.
Conrad Jackisch and Erwin Zehe
Hydrol. Earth Syst. Sci., 22, 3639–3662, https://doi.org/10.5194/hess-22-3639-2018, https://doi.org/10.5194/hess-22-3639-2018, 2018
Short summary
Short summary
We present a Lagrangian model for non-uniform soil water dynamics. It handles 2-D diffusion (based on a spatial random walk and implicit pore space redistribution) and 1-D advection in representative macropores (as film flow with dynamic interaction with the soil matrix). The interplay between the domains is calculated based on an energy-balance approach which does not require any additional parameterisation. Model tests give insight into the evolution of the non-uniform infiltration patterns.
Joop Kroes, Iwan Supit, Jos van Dam, Paul van Walsum, and Martin Mulder
Hydrol. Earth Syst. Sci., 22, 2937–2952, https://doi.org/10.5194/hess-22-2937-2018, https://doi.org/10.5194/hess-22-2937-2018, 2018
Short summary
Short summary
Impact of upward flow by capillary rise and recirculation on crop yields is often neglected or underestimated. Case studies and model experiments are used to illustrate the impact of this upward flow in the Dutch delta. Neglecting upward flow results in yield reductions for grassland, maize and potatoes. Half of the withheld water behind these yield effects comes from recirculated percolation water as occurs in free-drainage conditions; the other half from increased upward capillary rise.
Stefan Jaumann and Kurt Roth
Hydrol. Earth Syst. Sci., 22, 2551–2573, https://doi.org/10.5194/hess-22-2551-2018, https://doi.org/10.5194/hess-22-2551-2018, 2018
Short summary
Short summary
Ground-penetrating radar (GPR) is a noninvasive and nondestructive measurement method to monitor the hydraulic processes precisely and efficiently. We analyze synthetic as well as measured data from the ASSESS test site and show that the analysis yields accurate estimates for the soil hydraulic material properties as well as for the subsurface architecture by comparing the results to references derived from time domain reflectometry (TDR) and subsurface architecture ground truth data.
Gaochao Cai, Jan Vanderborght, Matthias Langensiepen, Andrea Schnepf, Hubert Hüging, and Harry Vereecken
Hydrol. Earth Syst. Sci., 22, 2449–2470, https://doi.org/10.5194/hess-22-2449-2018, https://doi.org/10.5194/hess-22-2449-2018, 2018
Short summary
Short summary
Different crop growths had consequences for the parameterization of root water uptake models. The root hydraulic parameters of the Couvreur model but not the water stress parameters of the Feddes–Jarvis model could be constrained by the field data measured from rhizotron facilities. The simulated differences in transpiration from the two soils and the different water treatments could be confirmed by sap flow measurements. The Couvreur model predicted the ratios of transpiration fluxes better.
Coleen D. U. Carranza, Martine J. van der Ploeg, and Paul J. J. F. Torfs
Hydrol. Earth Syst. Sci., 22, 2255–2267, https://doi.org/10.5194/hess-22-2255-2018, https://doi.org/10.5194/hess-22-2255-2018, 2018
Short summary
Short summary
Remote sensing has been popular for mapping surface soil moisture. However, estimating subsurface values using surface soil moisture remains a challenge, as decoupling can occur. Depth-integrated soil moisture values used in hydrological models are affected by vertical variability. Using statistical methods, we investigate vertical variability between the surface (5 cm) and subsurface (40 cm) to quantify decoupling. We also discuss potential controls for decoupling during wet and dry conditions.
Rafael Muñoz-Carpena, Claire Lauvernet, and Nadia Carluer
Hydrol. Earth Syst. Sci., 22, 53–70, https://doi.org/10.5194/hess-22-53-2018, https://doi.org/10.5194/hess-22-53-2018, 2018
Short summary
Short summary
Seasonal shallow water tables (WTs) in lowlands limit vegetation-buffer efficiency to control runoff pollution. Mechanistic models are needed to quantify true field efficiency. A new simplified algorithm for soil infiltration over WTs is tested against reference models and lab data showing WT effects depend on local settings but are negligible after 2 m depth. The algorithm is coupled to a complete vegetation buffer model in a companion paper to analyze pesticide and sediment control in situ.
Claire Lauvernet and Rafael Muñoz-Carpena
Hydrol. Earth Syst. Sci., 22, 71–87, https://doi.org/10.5194/hess-22-71-2018, https://doi.org/10.5194/hess-22-71-2018, 2018
Short summary
Short summary
Vegetation buffers, often placed in lowlands to control runoff pollution, can exhibit limited efficiency due to seasonal shallow water tables (WTs). A new shallow water table infiltration algorithm developed in a companion paper is coupled to a complete vegetation buffer model to quantify pesticide and sediment control in the field. We evaluated the model on two field experiments in France with and without WT conditions and show WTs can control efficiency depending on land and climate settings.
Tobias Karl David Weber, Sascha Christian Iden, and Wolfgang Durner
Hydrol. Earth Syst. Sci., 21, 6185–6200, https://doi.org/10.5194/hess-21-6185-2017, https://doi.org/10.5194/hess-21-6185-2017, 2017
Yonatan Ganot, Ran Holtzman, Noam Weisbrod, Ido Nitzan, Yoram Katz, and Daniel Kurtzman
Hydrol. Earth Syst. Sci., 21, 4479–4493, https://doi.org/10.5194/hess-21-4479-2017, https://doi.org/10.5194/hess-21-4479-2017, 2017
Short summary
Short summary
We monitor infiltration at multiple scales during managed aquifer recharge with desalinated seawater in an infiltration pond, while groundwater recharge is evaluated by simplified and numerical models. We found that pond-surface clogging is negated by the high-quality desalinated seawater or negligible compared to the low-permeability layers of the unsaturated zone. We show that a numerical model with a 1-D representative sediment profile is able to capture infiltration and recharge dynamics.
Stefan Jaumann and Kurt Roth
Hydrol. Earth Syst. Sci., 21, 4301–4322, https://doi.org/10.5194/hess-21-4301-2017, https://doi.org/10.5194/hess-21-4301-2017, 2017
Short summary
Short summary
We investigate the quantitative effect of neglected sensor position, small-scale heterogeneity, and lateral flow on soil hydraulic material properties. Thus, we analyze a fluctuating water table experiment in a 2-D architecture (ASSESS) with increasingly complex studies based on time domain reflectometry and hydraulic potential data. We found that 1-D studies may yield biased parameters and that estimating sensor positions as well as small-scale heterogeneity improves the model significantly.
Joseph Alexander Paul Pollacco, Trevor Webb, Stephen McNeill, Wei Hu, Sam Carrick, Allan Hewitt, and Linda Lilburne
Hydrol. Earth Syst. Sci., 21, 2725–2737, https://doi.org/10.5194/hess-21-2725-2017, https://doi.org/10.5194/hess-21-2725-2017, 2017
Short summary
Short summary
Descriptions of soil hydraulic properties, such as soil moisture release curve, θ(h), and saturated hydraulic conductivities, Ks, are a prerequisite for hydrological models. Because it is usually more difficult to describe Ks than θ(h) from pedotransfer functions, we developed a physical unimodal model to compute Ks solely from hydraulic parameters derived from the Kosugi θ(h). We further adaptations to this model to adapt it to dual-porosity structural soils.
Fadji Hassane Maina and Philippe Ackerer
Hydrol. Earth Syst. Sci., 21, 2667–2683, https://doi.org/10.5194/hess-21-2667-2017, https://doi.org/10.5194/hess-21-2667-2017, 2017
Short summary
Short summary
In many fields like climate change, hydrology and agronomy, water movement in unsaturated soils is usually simulated using the Richards equation. However, this equation requires lot of computational effort to be solved due to its highly nonlinear behavior, which hampers its use in simulations. In this paper, we analyze and developed some numerical strategies and we evaluate their reliability and efficiency.
Foad Foolad, Trenton E. Franz, Tiejun Wang, Justin Gibson, Ayse Kilic, Richard G. Allen, and Andrew Suyker
Hydrol. Earth Syst. Sci., 21, 1263–1277, https://doi.org/10.5194/hess-21-1263-2017, https://doi.org/10.5194/hess-21-1263-2017, 2017
Short summary
Short summary
Estimates of evapotranspiration are vital for validation of models. However, those datasets are often limited to research applications. Here, we explore using vadose zone modeling with widespread and readily available soil water content monitoring networks. While this work focused on one agricultural site, the framework can be used everywhere there is basic data. The resulting evapotranspiration and soil water content measurements are valuable benchmarks for evaluation of land surface models.
Justin Gibson, Trenton E. Franz, Tiejun Wang, John Gates, Patricio Grassini, Haishun Yang, and Dean Eisenhauer
Hydrol. Earth Syst. Sci., 21, 1051–1062, https://doi.org/10.5194/hess-21-1051-2017, https://doi.org/10.5194/hess-21-1051-2017, 2017
Short summary
Short summary
The human use of water for irrigation is often ignored in models and operational forecasts. We describe four plausible and relatively simple irrigation routines that can be coupled to the next generation of models. The routines are tested against a unique irrigation dataset from western Nebraska. The most aggressive water-saving irrigation routine indicates a potential irrigation savings of 120 mm yr−1 and yield losses of less than 3 % against the crop model benchmark and historical averages.
Marcos Alex dos Santos, Quirijn de Jong van Lier, Jos C. van Dam, and Andre Herman Freire Bezerra
Hydrol. Earth Syst. Sci., 21, 473–493, https://doi.org/10.5194/hess-21-473-2017, https://doi.org/10.5194/hess-21-473-2017, 2017
Short summary
Short summary
Some empirical root water uptake (RWU) models were assessed under varying environmental conditions predicted from numerical simulations with a detailed physical model. The widely used empirical RWU model by Feddes only performs well in scenarios of low RWU compensation. The RWU model by Jarvis cannot mimic the RWU patterns predicted by the physical model for high root length density scenarios. The two proposed models are more capable of predicting similar RWU patterns.
Ke Zhang, Xianwu Xue, Yang Hong, Jonathan J. Gourley, Ning Lu, Zhanming Wan, Zhen Hong, and Rick Wooten
Hydrol. Earth Syst. Sci., 20, 5035–5048, https://doi.org/10.5194/hess-20-5035-2016, https://doi.org/10.5194/hess-20-5035-2016, 2016
Short summary
Short summary
We developed a new approach to couple a distributed hydrological model, CREST, to a geotechnical landslide model, TRIGRS, to simulate both flood- and rainfall-triggered landslide hazards. By implementing more sophisticated and realistic representations of hydrological processes in the coupled model system, it shows better performance than the standalone landslide model in the case study. It highlights the important physical connection between rainfall, hydrological processes and slope stability.
Hannes H. Bauser, Stefan Jaumann, Daniel Berg, and Kurt Roth
Hydrol. Earth Syst. Sci., 20, 4999–5014, https://doi.org/10.5194/hess-20-4999-2016, https://doi.org/10.5194/hess-20-4999-2016, 2016
Short summary
Short summary
The representation of soil water movement comes with uncertainties in all model components. We assess the key uncertainties for the case of a one-dimensional soil profile with measured water contents. We employ a data assimilation method to represent and reduce the key uncertainties. For intermittent phases where model assumptions are violated, we introduce a "closed-eye period" to bridge the gap. We also demonstrate the need to include heterogeneity.
Muhammad Naveed, Per Moldrup, Marcel G. Schaap, Markus Tuller, Ramaprasad Kulkarni, Hans-Jörg Vogel, and Lis Wollesen de Jonge
Hydrol. Earth Syst. Sci., 20, 4017–4030, https://doi.org/10.5194/hess-20-4017-2016, https://doi.org/10.5194/hess-20-4017-2016, 2016
Short summary
Short summary
Quantification of rapid flow of water and associated transport of contaminants through large soil pores generated by earthworms or decaying plant roots is of crucial importance for sustaining both soil and water quality. Advanced visualization and analysis techniques based on state-of-the-art X-ray computed tomography have been applied to 65 soil cores extracted from an agricultural field in Silstrup, Denmark, to improve models for the prediction of fast, preferential flow processes in soils.
Erwin Zehe and Conrad Jackisch
Hydrol. Earth Syst. Sci., 20, 3511–3526, https://doi.org/10.5194/hess-20-3511-2016, https://doi.org/10.5194/hess-20-3511-2016, 2016
Cited articles
Allaire-Leung, S. E., Gupta, S. C., and Moncrief, J. F.: Water and solute movement in soil as influenced by macropore characteristics – 1. Macropore continuity, J. Contam. Hydrol., 41, 283–301, 2000.
Allen, R. G., Pereira, L. S., Raes, D., and Smith, M.: Crop evapotranspiration – Guidelines for computing crop water requirements – FAO Irrigation and drainage paper 56, FAO, Rome, Italy, 1998.
Alley, W. M.: On the Treatment of Evapotranspiration, Soil Moisture Accounting, and Aquifer Recharge in Monthly Water Balance Models, Water Resour. Res., 20, 1137–1149, 1984.
Andreini, M. S. and Steenhuis, T. S.: Preferential paths of flow under conventional and conservation tillage, Geoderma, 46, 85–102, 1990.
Beven, K. and Germann, P.: Macropores and water flow in soils, Water Resour. Res., 18, 1311–1325, 1982.
Butler, A. P., Hughes, A. G., Jackson, C. R., Ireson, A. M., Parker, S. J., Wheater, H. S., and Peach, D. W.: Advances in modelling groundwater behaviour in Chalk catchments (in Groundwater resources modelling; a case study from the UK) Geological Society Special Publications, 364, 113–127, 2012.
Cuthbert, M. O.: Hydraulic processes controlling recharge through glacial drift, PhD thesis, University of Birmingham, UK, 2006.
Cuthbert, M. O.: An improved time series approach for estimating groundwater recharge from groundwater level fluctuations, Water Resour. Res., 46, W09515, https://doi.org/10.1029/2009WR008572, 2010.
Cuthbert, M. O. and Tindimugaya, C.: The importance of preferential flow in controlling groundwater recharge in tropical Africa and implications for modelling the impact of climate change on groundwater resources, Journal of Water and Climate Change, 1, 234–245, 2010.
Cuthbert, M. O., Mackay, R., Tellam, J. H., and Barker, R. D.: The use of electrical resistivity tomography in deriving local scale models of recharge through superficial deposits, Q. J. Eng. Geol. Hydroge., 42, 199–209, 2009.
Cuthbert, M. O., Mackay, R., Tellam, J. H., and Thatcher, K. E.: Combining unsaturated and saturated zone hydraulic observations for understanding and estimating groundwater recharge through glacial till, J. Hydrol., 391, 263–276, 2010.
Frey, S. K., Rudolph, D. L., Lapen, D. R., and Ball Coelho, B. R.: Viscosity dependent dual-permeability modelling of liquid manure movement in layered, macroporous, tile drained soil, Water Resour. Res., 48, W00L11, https://doi.org/10.1029/2011WR010809, 2012.
Gerke, H. H. and van Genuchten, M. T.: A dual porosity model for simulating the preferential movement of water and solutes in structured porous media, Water Resour. Res., 29, 305–319, 1993.
Greswell, R., Ellis, P., Cuthbert, M., White, R., and Durand, V.: The design and application of an inexpensive pressure monitoring system for shallow water level measurement, tensiometry and piezometry, J. Hydrol., 373, 416–425, https://doi.org/10.1016/j.jhydrol.2009.05.001, 2009.
Hardie, M. A., Cotching, W. E., Doyle, R. B., Holz, G., Lisson, S., and Mattern K.: Effect of antecedent soil moisture on preferential flow in a texture-contrast soil, J. Hydrol., 398, 191–201, https://doi.org/10.1016/j.jhydrol.2010.12.008, 2011.
Healy, R. W.: Estimating Groundwater Recharge, 256 pp., Cambridge University Press, 2010.
Healy, R. W. and Cook, P. G.: Using groundwater levels to estimate recharge, Hydrogeol. J., 10, 91–109, 2002.
Heathcote, J. A., Lewis, R. T., and Soley, R. W. N.: Rainfall routing to runoff and recharge for regional groundwater resource models, Q. J. Eng. Geol. Hydroge., 37, 113–130, 2003.
Hincapié, I. and Germann, P.: Abstraction from Infiltrating Water Content Waves during Weak Viscous Flow, Vadose Zone J., 8, 996–1003, https://doi.org/10.2136/vzj2009.0012, 2009.
Hough, M. N. and Jones, R. J. A.: The United Kingdom Meteorological Office rainfall and evaporation calculation system: MORECS version 2.0 – an overview, Hydrol. Earth Syst. Sci., 1, 227–239, https://doi.org/10.5194/hess-1-227-1997, 1997.
Hulme, P., Rushton, K. R., and Fletcher, S.: Estimating recharge in UK catchments. Impact of Human Activity on Groundwater Dynamics (Proceedings of a symposium held during the Sixth IAHS Scientific Assembly at Maastricht, The Netherlands, July 2001), Maastricht, The Netherlands, IAHS, 33–42, 2001.
Ireson, A. M. and Butler, A. P.: Controls on preferential recharge to Chalk aquifers, J. Hydrol., 398, 109–123, 2011.
Lerner, D. N., Issar, A. S., and Simmers, I.: Groundwater Recharge, a Guide to Understanding and Estimating Natural Recharge, Report 8, 345 pp., International Association of Hydrogeologists, Kenilworth, 1990.
Mander, R. G. and Greenfield, B. J.: Hydrograph generation and augmented flow analysis, Thames Groundwater Scheme, Institution of Civil Engineers, 47–59, 1978.
Mirus, B. B. and Nimmo, J. R.: Balancing practicality and hydrologic realism: a parsimonious approach for simulating rapid groundwater recharge via unsaturated-zone preferential flow, Water Resour. Res., online first, https://doi.org/10.1002/WRCR.20141, 2013.
Mualem, Y.: A new model for predicting the hydraulic conductivity of unsaturated porous media, Water Resour. Res., 12, 513–522, 1976.
Nimmo, J. R.: Simple Predictions of Maximum Transport Rate in Unsaturated Soil and Rock, Water Resour. Res., 43, W05426, https://doi.org/10.1029/2006wr005372, 2007.
Nimmo, J. R.: Theory for Source-Responsive and Free-Surface Film Modeling of Unsaturated Flow, Vadose Zone J., 9, 295–306, https://doi.org/10.2136/vzj2009.0085, 2010.
Nimmo, J. R., Stonestrom, D. A., and Akstin, K. C.: The feasibility of recharge rate determinations using the steady-state centrifuge method, Soil Sci. Soc. Am. J., 58, 49–56, 1994.
Nimmo, J. R., Healy, R. W., and Stonestrom, D. A.: Aquifer Recharge, in Encyclopedia of Hydrological Science, edited by: Anderson, M. G. and Bear, J., 4, 2229–2246, Wiley, Chichester, UK, 2005.
Rosenbom, A. E., Ernstsen, V., Flühler, H., Jensen, K. H., Refsgaard, J. C., and Wydler, H.: Fluorescence Imaging Applied to Tracer Distributions in Variably Saturated Fractured Clayey Till, J. Environ. Qual., 37, 448–458, https://doi.org/10.2134/jeq2007.0145, 2008.
Rushton, K. R., Eilers, V. H. M., and Carter, R. C.: Improved soil moisture balance methodology for recharge estimation, J. Hydrol., 318, 379–399, 2006.
Scanlon, B. R., Healy, R. W., and Cook, P. G.: Choosing appropriate techniques for quantifying groundwater recharge, Hydrogeol. J., 10, 18–39, 2002.
Shipitalo, M. J. and Edwards, W. M.: Effects of Initial Water Content on Macropore/Matrix Flow and Transport of Surface-Applied Chemicals, J. Environ. Qual., 25, 662–670, 1996.
Šimůnek, J., Jarvis, N. J., van Genuchten, M. T., and Gardenas, A.: Review and comparison of models for describing non-equilibrium and preferential flow and transport in the vadose zone, J. Hydrol., 272, 14–35, 2003.
Šimůnek, J., van Genuchten, M. T., and Šejna, M.: The HYDRUS Software Package for Simulating Two- and Three-Dimensional Movement of Water, Heat, and Multiple Solutes in Variably-Saturated Media, Technical Manual, Version 2.0, PC Progress, Prague, Czech Republic, 258 pp., 2011.
Streetly, M. and Shepley, M. G.: Final Report, East Shropshire Permo-Triassic Sandstone Groundwater Modelling Project – Task 8. Report of the Environment Agency of England and Wales, UK, 2005.
Su, G. W., Nimmo, J. R., and Dragila, M. I.: Effect of isolated fractures on accelerated flow in unsaturated porous rock, Water Resour. Res., 39, 1326, https://doi.org/10.1029/2002WR001691, 2003.
Thatcher, K. E.: Spatial Characterisation and stochastic analysis of unsaturated flows and groundwater recharge through glacial drift, PhD thesis, University of Birmingham, UK, 2009.
van Genuchten, M. T.: A closed-form equation for predicting the hydraulic conductivity of unsaturated soils, Soil Sci. Soc. Am. J., 44, 892–898, 1980.
Special issue