Articles | Volume 21, issue 12
https://doi.org/10.5194/hess-21-6185-2017
© Author(s) 2017. 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-21-6185-2017
© Author(s) 2017. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
A pore-size classification for peat bogs derived from unsaturated hydraulic properties
Tobias Karl David Weber
CORRESPONDING AUTHOR
Soil Science and Soil Physics Division, Institute of Geoecology, Technische Universität Braunschweig, Langer Kamp 19c, 38106 Braunschweig, Germany
now at: Institute of Soil Science and Land Evaluation, University of Hohenheim, 70593 Stuttgart, Germany
Sascha Christian Iden
Soil Science and Soil Physics Division, Institute of Geoecology, Technische Universität Braunschweig, Langer Kamp 19c, 38106 Braunschweig, Germany
Wolfgang Durner
Soil Science and Soil Physics Division, Institute of Geoecology, Technische Universität Braunschweig, Langer Kamp 19c, 38106 Braunschweig, Germany
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Pedotransfer functions (PTFs) are used to predict parameters of models describing the hydraulic properties of soils. The appropriateness of these predictions critically relies on the nature of the datasets for training the PTFs and the physical comprehensiveness of the models. This roadmap paper is addressed to PTF developers and users and critically reflects the utility and future of PTFs. To this end, we present a manifesto aiming at a paradigm shift in PTF research.
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Measurements of soil water retention properties play an important role in a variety of societal issues that depend on soil water conditions. However, there is little concern about the consistency of these measurements between laboratories. We conducted an interlaboratory comparison to assess the reproducibility of the measurement of the soil water retention curve. Results highlight the need to harmonize and standardize procedures to improve the description of unsaturated processes in soils.
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Geosci. Instrum. Method. Data Syst., 12, 25–44, https://doi.org/10.5194/gi-12-25-2023, https://doi.org/10.5194/gi-12-25-2023, 2023
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Important topics in land–atmosphere feedback research are water and energy balances and heterogeneities of fluxes at the land surface and in the atmosphere. To target these questions, the Land–Atmosphere Feedback Observatory (LAFO) has been installed in Germany. The instrumentation allows for comprehensive measurements from the bedrock to the troposphere. The LAFO observation strategy aims for simultaneous measurements in all three compartments: atmosphere, soil and land surface, and vegetation.
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We analysed the evolution of model parameter uncertainty and prediction error as we updated parameters of a maize phenology model based on yearly observations, by sequentially applying Bayesian calibration. Although parameter uncertainty was reduced, prediction quality deteriorated when calibration and prediction data were from different maize ripening groups or temperature conditions. The study highlights that Bayesian methods should account for model limitations and inherent data structures.
Tobias K. D. Weber, Joachim Ingwersen, Petra Högy, Arne Poyda, Hans-Dieter Wizemann, Michael Scott Demyan, Kristina Bohm, Ravshan Eshonkulov, Sebastian Gayler, Pascal Kremer, Moritz Laub, Yvonne Funkiun Nkwain, Christian Troost, Irene Witte, Tim Reichenau, Thomas Berger, Georg Cadisch, Torsten Müller, Andreas Fangmeier, Volker Wulfmeyer, and Thilo Streck
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Presented are measurement results from six agricultural fields operated by local farmers in southwestern Germany over 9 years. Six eddy-covariance stations measuring water, energy, and carbon fluxes between the vegetated soil surface and the atmosphere provided the backbone of the measurement sites and were supplemented by extensive soil and vegetation state monitoring. The dataset is ideal for testing process models characterizing fluxes at the vegetated soil surface and in the atmosphere.
Brigitta Szabó, Melanie Weynants, and Tobias K. D. Weber
Geosci. Model Dev., 14, 151–175, https://doi.org/10.5194/gmd-14-151-2021, https://doi.org/10.5194/gmd-14-151-2021, 2021
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This paper presents updated European prediction algorithms (euptf2) to compute soil hydraulic parameters from easily available soil properties. The new algorithms lead to significantly better predictions and provide a built-in prediction uncertainty computation. The influence of predictor variables on predicted soil hydraulic properties is explored and practical guidance on how to use the derived PTFs is provided. A website and an R package facilitate easy application of the updated predictions.
Ravshan Eshonkulov, Arne Poyda, Joachim Ingwersen, Hans-Dieter Wizemann, Tobias K. D. Weber, Pascal Kremer, Petra Högy, Alim Pulatov, and Thilo Streck
Biogeosciences, 16, 521–540, https://doi.org/10.5194/bg-16-521-2019, https://doi.org/10.5194/bg-16-521-2019, 2019
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We compared the energy balance closure (EBC) under varying environmental conditions and investigated a wide range of possible reasons for the energy imbalance. As measures for the imbalance, we used ordinary linear regression, the energy balance ratio (EBR), and the energy residual. The EBR was also investigated as a function of buoyancy, friction velocity, and atmospheric stability. Moreover, the relationship between the EBC and flux source area or footprint was also investigated.
Reuven B. Simhayov, Tobias K. D. Weber, and Jonathan S. Price
SOIL, 4, 63–81, https://doi.org/10.5194/soil-4-63-2018, https://doi.org/10.5194/soil-4-63-2018, 2018
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Lab experiments were performed to understand solute transport in peat from an experimental fen. Transport was analyzed under saturated and unsaturated conditions using NaCl (salt). We tested the applicability of a physical-based model which finds a wide consensus vs. alternative models. Evidence indicated that Cl transport can be explained using a simple transport model. Hence, use of the physical transport mechanism in peat should be evidence based and not automatically assumed.
Tobias Karl David Weber, Lutz Weihermüller, Attila Nemes, Michel Bechtold, Aurore Degré, Efstathios Diamantopoulos, Simone Fatichi, Vilim Filipović, Surya Gupta, Tobias L. Hohenbrink, Daniel R. Hirmas, Conrad Jackisch, Quirijn de Jong van Lier, John Koestel, Peter Lehmann, Toby R. Marthews, Budiman Minasny, Holger Pagel, Martine van der Ploeg, Shahab Aldin Shojaeezadeh, Simon Fiil Svane, Brigitta Szabó, Harry Vereecken, Anne Verhoef, Michael Young, Yijian Zeng, Yonggen Zhang, and Sara Bonetti
Hydrol. Earth Syst. Sci., 28, 3391–3433, https://doi.org/10.5194/hess-28-3391-2024, https://doi.org/10.5194/hess-28-3391-2024, 2024
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Pedotransfer functions (PTFs) are used to predict parameters of models describing the hydraulic properties of soils. The appropriateness of these predictions critically relies on the nature of the datasets for training the PTFs and the physical comprehensiveness of the models. This roadmap paper is addressed to PTF developers and users and critically reflects the utility and future of PTFs. To this end, we present a manifesto aiming at a paradigm shift in PTF research.
Andre Peters, Sascha C. Iden, and Wolfgang Durner
Hydrol. Earth Syst. Sci., 27, 4579–4593, https://doi.org/10.5194/hess-27-4579-2023, https://doi.org/10.5194/hess-27-4579-2023, 2023
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While various expressions for the water retention curve are commonly compared, the capillary conductivity model proposed by Mualem is widely used but seldom compared to alternatives. We compare four different capillary bundle models in terms of their ability to fully predict the hydraulic conductivity. The Mualem model outperformed the three other models in terms of predictive accuracy. Our findings suggest that the widespread use of the Mualem model is justified.
Tobias L. Hohenbrink, Conrad Jackisch, Wolfgang Durner, Kai Germer, Sascha C. Iden, Janis Kreiselmeier, Frederic Leuther, Johanna C. Metzger, Mahyar Naseri, and Andre Peters
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Benjamin Guillaume, Hanane Aroui Boukbida, Gerben Bakker, Andrzej Bieganowski, Yves Brostaux, Wim Cornelis, Wolfgang Durner, Christian Hartmann, Bo V. Iversen, Mathieu Javaux, Joachim Ingwersen, Krzysztof Lamorski, Axel Lamparter, András Makó, Ana María Mingot Soriano, Ingmar Messing, Attila Nemes, Alexandre Pomes-Bordedebat, Martine van der Ploeg, Tobias Karl David Weber, Lutz Weihermüller, Joost Wellens, and Aurore Degré
SOIL, 9, 365–379, https://doi.org/10.5194/soil-9-365-2023, https://doi.org/10.5194/soil-9-365-2023, 2023
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Measurements of soil water retention properties play an important role in a variety of societal issues that depend on soil water conditions. However, there is little concern about the consistency of these measurements between laboratories. We conducted an interlaboratory comparison to assess the reproducibility of the measurement of the soil water retention curve. Results highlight the need to harmonize and standardize procedures to improve the description of unsaturated processes in soils.
Andre Peters, Tobias L. Hohenbrink, Sascha C. Iden, Martinus Th. van Genuchten, and Wolfgang Durner
Hydrol. Earth Syst. Sci., 27, 1565–1582, https://doi.org/10.5194/hess-27-1565-2023, https://doi.org/10.5194/hess-27-1565-2023, 2023
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The soil hydraulic conductivity function is usually predicted from the water retention curve (WRC) with the requirement of at least one measured conductivity data point for scaling the function. We propose a new scheme of absolute hydraulic conductivity prediction from the WRC without the need of measured conductivity data. Testing the new prediction with independent data shows good results. This scheme can be used when insufficient or no conductivity data are available.
Florian Späth, Verena Rajtschan, Tobias K. D. Weber, Shehan Morandage, Diego Lange, Syed Saqlain Abbas, Andreas Behrendt, Joachim Ingwersen, Thilo Streck, and Volker Wulfmeyer
Geosci. Instrum. Method. Data Syst., 12, 25–44, https://doi.org/10.5194/gi-12-25-2023, https://doi.org/10.5194/gi-12-25-2023, 2023
Short summary
Short summary
Important topics in land–atmosphere feedback research are water and energy balances and heterogeneities of fluxes at the land surface and in the atmosphere. To target these questions, the Land–Atmosphere Feedback Observatory (LAFO) has been installed in Germany. The instrumentation allows for comprehensive measurements from the bedrock to the troposphere. The LAFO observation strategy aims for simultaneous measurements in all three compartments: atmosphere, soil and land surface, and vegetation.
Michelle Viswanathan, Tobias K. D. Weber, Sebastian Gayler, Juliane Mai, and Thilo Streck
Biogeosciences, 19, 2187–2209, https://doi.org/10.5194/bg-19-2187-2022, https://doi.org/10.5194/bg-19-2187-2022, 2022
Short summary
Short summary
We analysed the evolution of model parameter uncertainty and prediction error as we updated parameters of a maize phenology model based on yearly observations, by sequentially applying Bayesian calibration. Although parameter uncertainty was reduced, prediction quality deteriorated when calibration and prediction data were from different maize ripening groups or temperature conditions. The study highlights that Bayesian methods should account for model limitations and inherent data structures.
Tobias K. D. Weber, Joachim Ingwersen, Petra Högy, Arne Poyda, Hans-Dieter Wizemann, Michael Scott Demyan, Kristina Bohm, Ravshan Eshonkulov, Sebastian Gayler, Pascal Kremer, Moritz Laub, Yvonne Funkiun Nkwain, Christian Troost, Irene Witte, Tim Reichenau, Thomas Berger, Georg Cadisch, Torsten Müller, Andreas Fangmeier, Volker Wulfmeyer, and Thilo Streck
Earth Syst. Sci. Data, 14, 1153–1181, https://doi.org/10.5194/essd-14-1153-2022, https://doi.org/10.5194/essd-14-1153-2022, 2022
Short summary
Short summary
Presented are measurement results from six agricultural fields operated by local farmers in southwestern Germany over 9 years. Six eddy-covariance stations measuring water, energy, and carbon fluxes between the vegetated soil surface and the atmosphere provided the backbone of the measurement sites and were supplemented by extensive soil and vegetation state monitoring. The dataset is ideal for testing process models characterizing fluxes at the vegetated soil surface and in the atmosphere.
Mahyar Naseri, Sascha C. Iden, and Wolfgang Durner
SOIL, 8, 99–112, https://doi.org/10.5194/soil-8-99-2022, https://doi.org/10.5194/soil-8-99-2022, 2022
Short summary
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We simulated stony soils with low to high volumes of rock fragments in 3D using evaporation and multistep unit-gradient experiments. Hydraulic properties of virtual stony soils were identified under a wide range of soil matric potentials. The developed models for scaling the hydraulic conductivity of stony soils were evaluated under unsaturated flow conditions.
Brigitta Szabó, Melanie Weynants, and Tobias K. D. Weber
Geosci. Model Dev., 14, 151–175, https://doi.org/10.5194/gmd-14-151-2021, https://doi.org/10.5194/gmd-14-151-2021, 2021
Short summary
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This paper presents updated European prediction algorithms (euptf2) to compute soil hydraulic parameters from easily available soil properties. The new algorithms lead to significantly better predictions and provide a built-in prediction uncertainty computation. The influence of predictor variables on predicted soil hydraulic properties is explored and practical guidance on how to use the derived PTFs is provided. A website and an R package facilitate easy application of the updated predictions.
Conrad Jackisch, Kai Germer, Thomas Graeff, Ines Andrä, Katrin Schulz, Marcus Schiedung, Jaqueline Haller-Jans, Jonas Schneider, Julia Jaquemotte, Philipp Helmer, Leander Lotz, Andreas Bauer, Irene Hahn, Martin Šanda, Monika Kumpan, Johann Dorner, Gerrit de Rooij, Stefan Wessel-Bothe, Lorenz Kottmann, Siegfried Schittenhelm, and Wolfgang Durner
Earth Syst. Sci. Data, 12, 683–697, https://doi.org/10.5194/essd-12-683-2020, https://doi.org/10.5194/essd-12-683-2020, 2020
Short summary
Short summary
Soil water content and matric potential are central hydrological state variables. A large variety of automated probes and sensor systems for field monitoring exist. In a field experiment under idealised conditions we compared 15 systems for soil moisture and 14 systems for matric potential. The individual records of one system agree well with the others. Most records are also plausible. However, the absolute values of the different measuring systems span a very large range of possible truths.
Ravshan Eshonkulov, Arne Poyda, Joachim Ingwersen, Hans-Dieter Wizemann, Tobias K. D. Weber, Pascal Kremer, Petra Högy, Alim Pulatov, and Thilo Streck
Biogeosciences, 16, 521–540, https://doi.org/10.5194/bg-16-521-2019, https://doi.org/10.5194/bg-16-521-2019, 2019
Short summary
Short summary
We compared the energy balance closure (EBC) under varying environmental conditions and investigated a wide range of possible reasons for the energy imbalance. As measures for the imbalance, we used ordinary linear regression, the energy balance ratio (EBR), and the energy residual. The EBR was also investigated as a function of buoyancy, friction velocity, and atmospheric stability. Moreover, the relationship between the EBC and flux source area or footprint was also investigated.
Reuven B. Simhayov, Tobias K. D. Weber, and Jonathan S. Price
SOIL, 4, 63–81, https://doi.org/10.5194/soil-4-63-2018, https://doi.org/10.5194/soil-4-63-2018, 2018
Short summary
Short summary
Lab experiments were performed to understand solute transport in peat from an experimental fen. Transport was analyzed under saturated and unsaturated conditions using NaCl (salt). We tested the applicability of a physical-based model which finds a wide consensus vs. alternative models. Evidence indicated that Cl transport can be explained using a simple transport model. Hence, use of the physical transport mechanism in peat should be evidence based and not automatically assumed.
M. Hannes, U. Wollschläger, F. Schrader, W. Durner, S. Gebler, T. Pütz, J. Fank, G. von Unold, and H.-J. Vogel
Hydrol. Earth Syst. Sci., 19, 3405–3418, https://doi.org/10.5194/hess-19-3405-2015, https://doi.org/10.5194/hess-19-3405-2015, 2015
B. Scharnagl, S. C. Iden, W. Durner, H. Vereecken, and M. Herbst
Hydrol. Earth Syst. Sci. Discuss., https://doi.org/10.5194/hessd-12-2155-2015, https://doi.org/10.5194/hessd-12-2155-2015, 2015
Preprint withdrawn
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Subject: Vadose Zone Hydrology | Techniques and Approaches: Modelling approaches
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Hydrol. Earth Syst. Sci., 28, 4035–4057, https://doi.org/10.5194/hess-28-4035-2024, https://doi.org/10.5194/hess-28-4035-2024, 2024
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Meirav Cohen, Nimrod Schwartz, and Ravid Rosenzweig
Hydrol. Earth Syst. Sci., 28, 1585–1604, https://doi.org/10.5194/hess-28-1585-2024, https://doi.org/10.5194/hess-28-1585-2024, 2024
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Lukas Strebel, Heye Bogena, Harry Vereecken, Mie Andreasen, Sergio Aranda-Barranco, and Harrie-Jan Hendricks Franssen
Hydrol. Earth Syst. Sci., 28, 1001–1026, https://doi.org/10.5194/hess-28-1001-2024, https://doi.org/10.5194/hess-28-1001-2024, 2024
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We present results from using soil water content measurements from 13 European forest sites in a state-of-the-art land surface model. We use data assimilation to perform a combination of observed and modeled soil water content and show the improvements in the representation of soil water content. However, we also look at the impact on evapotranspiration and see no corresponding improvements.
Yanling Wang, Liangsheng Shi, Yaan Hu, Xiaolong Hu, Wenxiang Song, and Lijun Wang
Hydrol. Earth Syst. Sci., 28, 917–943, https://doi.org/10.5194/hess-28-917-2024, https://doi.org/10.5194/hess-28-917-2024, 2024
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LSTM temporal modeling suits soil moisture prediction; attention mechanisms enhance feature learning efficiently, as their feature selection capabilities are proven through Transformer and attention–LSTM hybrids. Adversarial training strategies help extract additional information from time series’ data. SHAP analysis and t-SNE visualization reveal differences in encoded features across models. This work serves as a reference for time series’ data processing in hydrology problems.
Christoph Neukum, Angela Morales-Santos, Melanie Ronelngar, Aminu Bala, and Sara Vassolo
Hydrol. Earth Syst. Sci., 27, 3601–3619, https://doi.org/10.5194/hess-27-3601-2023, https://doi.org/10.5194/hess-27-3601-2023, 2023
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A generalized approach that requires limited field data and well-established models is tested for assessing groundwater recharge in the southern Lake Chad basin. E and T coefficients are estimated with the FAO-dual Kc concept at six locations. Measured soil water content and chloride concentrations along vertical soil profiles together with different scenarios for E and T partitioning and a Bayesian calibration approach are used to simulate water flow and chloride transport using Hydrus-1D.
Moreen Willaredt, Thomas Nehls, and Andre Peters
Hydrol. Earth Syst. Sci., 27, 3125–3142, https://doi.org/10.5194/hess-27-3125-2023, https://doi.org/10.5194/hess-27-3125-2023, 2023
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This study proposes a model to predict soil hydraulic properties (SHPs) of constructed Technosols for urban greening. The SHPs are determined by the Technosol composition and describe their capacity to store and supply water to plants. The model predicts SHPs of any binary mixture based on the SHPs of its two pure components, facilitating simulations of flow and transport processes before production. This can help create Technosols designed for efficient urban greening and water management.
Pengxiang Wang, Zuhao Zhou, Jiajia Liu, Chongyu Xu, Kang Wang, Yangli Liu, Jia Li, Yuqing Li, Yangwen Jia, and Hao Wang
Hydrol. Earth Syst. Sci., 27, 2681–2701, https://doi.org/10.5194/hess-27-2681-2023, https://doi.org/10.5194/hess-27-2681-2023, 2023
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Considering the impact of the special geological and climatic conditions of the Qinghai–Tibet Plateau on the hydrological cycle, this study established the WEP-QTP hydrological model. The snow cover and gravel layers affected the temporal and spatial changes in frozen soil and improved the regulation of groundwater on the flow process. Ignoring he influence of special underlying surface conditions has a great impact on the hydrological forecast and water resource utilization in this area.
Antoine Sobaga, Bertrand Decharme, Florence Habets, Christine Delire, Noële Enjelvin, Paul-Olivier Redon, Pierre Faure-Catteloin, and Patrick Le Moigne
Hydrol. Earth Syst. Sci., 27, 2437–2461, https://doi.org/10.5194/hess-27-2437-2023, https://doi.org/10.5194/hess-27-2437-2023, 2023
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Seven instrumented lysimeters are used to assess the simulation of the soil water dynamic in one land surface model. Four water potential and hydraulic conductivity closed-form equations, including one mixed form, are evaluated. One form is more relevant for simulating drainage, especially during intense drainage events. The soil profile heterogeneity of one parameter of the closed-form equations is shown to be important.
Sebastián Páez-Bimos, Armando Molina, Marlon Calispa, Pierre Delmelle, Braulio Lahuatte, Marcos Villacís, Teresa Muñoz, and Veerle Vanacker
Hydrol. Earth Syst. Sci., 27, 1507–1529, https://doi.org/10.5194/hess-27-1507-2023, https://doi.org/10.5194/hess-27-1507-2023, 2023
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This study analyzes 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 type. 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.
Marleen Schübl, Giuseppe Brunetti, Gabriele Fuchs, and Christine Stumpp
Hydrol. Earth Syst. Sci., 27, 1431–1455, https://doi.org/10.5194/hess-27-1431-2023, https://doi.org/10.5194/hess-27-1431-2023, 2023
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Estimating groundwater recharge through the unsaturated zone is a difficult task that is fundamentally associated with uncertainties. One of the few methods available is inverse modeling based on soil water measurements. Here, 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.
Jakub Kmec, Miloslav Šír, Tomáš Fürst, and Rostislav Vodák
Hydrol. Earth Syst. Sci., 27, 1279–1300, https://doi.org/10.5194/hess-27-1279-2023, https://doi.org/10.5194/hess-27-1279-2023, 2023
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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.
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
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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
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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
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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.
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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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.
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
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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
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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
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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
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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.
Cited articles
Assouline, S., Tessier, D., and Bruand, A.: A conceptual model of the soil water retention curve, Water Resour. Res., 34, 223–231, 1998.
Balyea, L. R.: Nonlinear Dynamics of Peatlands and Potential Feedbacks on the Climate System, in: Carbon Cycling in Northern Peatlands, Geophysical Monograph 184, Geophysical Monograph Series, edited by: Baird, A. J., Belyea, L. R., Comas, X., Reeve, A. S., and Slater, L. D., American Geophysical Union, Washington, D.C., 2009.
Baumann, K.: Entwicklung der Moorvegetation im Nationalpark Harz, in: Schriftenreihe aus dem Nationalpark Harz, Band 4, Nationalpark Harz, Wernigerode, 2009.
Blume, H.-P., Brümmer, G. W., Fleige, H., Horn, R., Kandeler, E., Kögel-Knabner, I., Kretzschmar, R., Stahr, K., and Wilke, B.-M.: Scheffer/Schachtschabel Soil Science, Springer, Berlin, Heidelberg, 618 pp., https://doi.org/10.1007/978-3-642-30942-7, 2016.
Boelter, D. H.: Physical Properties of Peat as related to degree of decomposition, Soil Sci Soc Am Proc, 33, 606-609, 1969.
Branham, J. E. and Strack, M.: Saturated hydraulic conductivity in Sphagnum-dominated peatlands: do microforms matter?, Hydrol. Process., 28, 4161–4387, https://doi.org/10.1002/hyp.10228 2014.
Broder, T. and Biester, H.: Hydrologic controls on DOC, As and Pb export from a polluted peatland – the importance of heavy rain events, antecedent moisture conditions and hydrological connectivity, Biogeosciences, 12, 4651–4664, https://doi.org/10.5194/bg-12-4651-2015, 2015.
Clymo, R. S.: The growth of Sphagnum: methods of measurement, J. Ecol., 58, 13–40, 1970.
Clymo, R. S.: The growth of Sphagnum: some effects of environment, J. Ecol., 61, 849–869, 1973.
Clymo, R. S.: A model of peat-bog growth. Production Ecology of some British Moors and Montane Grasslands, edited by: Heal, O. W., Perkins, D. F., and Brown, W. M., Springer, Berlin, 187–223, 1978.
Clymo, R. S.: The Limits to Peat Bog Growth, Philos. T. Roy. Soc. B, 303, 605–654, 1984.
Clymo, R. S. and Hayward, P. M.: Ecology of Sphagnum, in: Bryophyte Ecology, Chapman and Hall, London, UK, 229–289, 1982.
Dettmann, U. and Bechtold, M.: Deriving effective soil water retention characteristics from shallow water table fluctuations in peatlands, Vadose Zone J., 15, 1–13, https://doi.org/10.2136/vzj2016.04.0029, 2016.
Dimitrov, D. D., Grant, R. F., Lafleur, P. M., and Humphreys, E. R.: Modeling the effects of hydrology on ecosystem respiration at Mer Bleue bog, J. Geophys. Res., 115, G04043, https://doi.org/10.1029/2010JG001312, 2010.
Durner, W.: Hydraulic conductivity estimation for soils with heterogeneous pore structure, Water Resour. Res., 30, 211–223, 1994.
Durner, W. and Iden, S. C.: Extended multistep outflow method for the accurate determination of soil hydraulic properties near water saturation, Water Resour. Res., 47, W08526, https://doi.org/10.1029/2011WR010632, 2011.
Durner, W., Jansen, U., and Iden, S. C.: Effective hydraulic properties of layered soils at the lysimeter scale determined by inverse modelling, Eur. J. Soil Sci., 59, 114–124, https://doi.org/10.1111/j.1365-2389.2007.00972.x, 2008.
Frolking, S. and Roulet, N. T.: Holocene radiative forcing impact of northern peatland carbon accumulation and methane emissions, Global Change Biol., 13, 1079–1088, 2007.
Glaser, P. H., Chasar, L. I., Chanton, J. P., Morin, P., Rosenberry, D. O., Siegel, D. I., Ruud, O., and Reeve, A. S.: Surface deformations as indicators of deep ebullition fluxes in a large northern peatland, Global Biogeochem. Cy., 18, GB1003, https://doi.org/10.1029/2003GB002069, 2004.
Goetz, J. and Price, J. S.: Role of morphological structure and layering of Sphagnum and Tomenthypnum mosses on moss productivity and evaporation rates, Can. J. Soil Sci., 95, 109–124, https://doi.org/10.4141/CJSS-2014-092, 2015.
Hájek, T. and Beckett, R. P.: Effect of Water Content Components on Desiccation and Recovery in Sphagnum Mosses, Ann. Bot., 101, 165–173, https://doi.org/10.1093/aob/mcm287, 2008.
Hayward, P. M. and Clymo, R. S.: Profiles of Water Content and Pore Size in Sphagnum and Peat, and their Relation to Peat Bog Ecology, P. Roy. Soc. B, 215, 299–325, https://doi.org/10.1098/rspb.1982.0044, 1982.
Hedwall, P.-O., Brunet, J., and Rydin, H.: Peatland plant communities under global change: negative feedback loops counteract shifts in species composition, Ecology, 98, 150–161, https://doi.org/10.1002/ecy.1627, 2017.
Hoffmann-Riem, H., van Genuchten, M. T., and Flühler, H.: A general model of the hydraulic conductivity of unsaturated soils, in: Proceedings of International Workshop, Characterization and Measurements of the Hydraulic Properties of Unsaturated Porous Media, edited by: van Genuchten, M. T., Leij, F. J., and Wu, L., University of California, Riverside, CA, 31–42, 1999.
Holden, J.: Piping and woody plants in peatlands: Cause or effect?, Water Resour. Res., 41, W06009, https://doi.org/10.1029/2004WR003909, 2005.
Iden, S. C. and Durner, W.: Comment on “Simple consistent models for water retention and hydraulic conductivity in the complete moisture range” by A. Peters, Water Resour. Res., 50, 1–5, https://doi.org/10.1002/2014WR015937, 2014.
Ingram, H. A. P.: Soil layers in mires: function and terminology, J. Soil Sci., 29, 224–227, 1978.
Jensen, U.: Die Moore des Hochharzes. Spezieller Teil, Niedersächsisches Landesverwaltungsamt, Hannover, Germany, 1990.
Johnson, L. C., Damman, A. W. H., and Malmer, N.: Sphagnum macrostructure as an indicator of decay and compaction in peat cores from an ombrotrophic south Swedish peat-bog, J. Ecol., 78, 633–647, 1990.
Jones, C. G., Lawton, J. H., and Shachak, M.: Organisms as ecosystem engineers, Oikos, 69, 373–386, 1994.
Jury, W. and Horton, R.: Soil Physics, 6th Edition John Wiley & Sons, New York, p. 390, 2004.
Kettridge, N. and Binley, A.: Characterization of peat structure using X-ray computed tomography and its control on ebullition of biogenic gas bubbles, J. Geophys. Res., 116, G01024, https://doi.org/10.1029/2010JG001478, 2011.
Klute, A. and Dirksen, C.: Hydraulic conductivity and diffusivity: laboratory methods, in: Methods of Soil Analysis, Part 1. Physical and Mineralogical Methods, edited by: Klute, A., American Society of Agronomy, Inc., Madison, WI, 687–734, 1986.
Kuhry, P. and Vitt, D.: Fossil carbon/nitrogen ratios as a measure of peat decomposition, Ecology, 77, 271–275, 1996.
Lewis, A. M.: A test of the air-seeding hypothesis using Sphagnum hyalocysts, Plant Physiol., 87, 577–582, https://doi.org/10.1104/87.3.577, 1988.
Limpens, J., Berendse, F., Blodau, C., Canadell, J. G., Freeman, C., Holden, J., Roulet, N., Rydin, H., and Schaepman-Strub, G.: Peatlands and the carbon cycle: from local processes to global implications – a synthesis, Biogeosciences, 5, 1475–1491, https://doi.org/10.5194/bg-5-1475-2008, 2008.
McCarter, C. P. R. and Price, J. S.: Ecohydrology of Sphagnum moss hummocks: mechanisms of capitula water supply and simulated effects of evaporation, Ecohydrology, 7, 33–44, https://doi.org/10.1002/eco.1313, 2012.
McCarter, C. P. R. and Price, J. S.: The hydrology of the Bois-des-Bel peatland restoration: hydrophysical properties limiting connectivity between regenerated Sphagnum and remnant vacuum harvested peat deposit, Ecohydrology, 8, 173–187, https://doi.org/10.1002/eco.1498, 2014.
McCarter, C. P. R., Ketcheson, S., Weber, T. K. D., Whittington, P., Scarlett, S., and Price, J. S.: A modified technique for measuring unsaturated hydraulic conductivity in Sphagnum moss and peat, Soil Sci. Soc. Am. J., 81, 747–757, https://doi.org/10.2136/sssaj2017.01.0006, 2017.
Meiers, G. P., Barbour, S. L., Qualizza, C. V., and Dobchuk, B. S.: Evolution of the Hydraulic Conductivity of Reclamation Covers over Sodic/Saline Mining Overburden, J. Geotech. Geoenviron. Eng., 137, 968–976, https://doi.org/10.1061/(ASCE)GT.1943-5606.0000523, 2013.
Mezbahuddin, M., Grant, R. F., and Flanagan, L. B.: Modeling hydrological controls on variations in peat water content, water table depth, and surface energy exchange of a boreal western Canadian fen peatland, J. Geophys. Res.-Biogeo., 121, 2216–2242, https://doi.org/10.1002/2016JG003501, 2016.
Michaelis, D.: Die Sphagnum-Arten der Welt, Bibliotheca Botanica, 160, p. 408, 2011.
Morris, P. J., Baird, A. J., and Belyea, L. R.: Ecohydrological feedbacks in peatland development: a theoretical modelling study, J. Ecol., 99, 1190–1201, https://doi.org/10.1111/j.1365-2745.2011.01842.x, 2011.
Morris, P. J., Baird, A. J., and Belyea, L. R.: Bridging the gap between models and measurements of peat hydraulic conductivity, Water Resour. Res., 51, 5353–5364, https://doi.org/10.1002/2015WR017264, 2015.
Mualem, Y.: New model for redicting hydraulic conductivity of unsaturated porous, Water Resour. Res., 12, 513–522, 1976.
Mullen, K., Ardia, D., Gil, D., Windover, D., and Cline, J.: `DEoptim': An R Package for Global Optimization by Differential Evolution, J. Stat. Softw., 40, 1–26, 2011.
Peters, A.: Simple consistent models for water retention and hydraulic conductivity in the complete moisture range, Water Resour. Res., 49, 6765–6780, https://doi.org/10.1002/wrcr.20548, 2013.
Peters, A.: Reply to comment by S. Iden and W. Durner on “Simple consistent models for water retention and hydraulic conductivity in the complete moisture range”, Water Resour. Res., 50, 7535–7539, https://doi.org/10.1002/2014WR016107, 2014.
Peters, A. and Durner, W.: Simplified evaporation method for determining soil hydraulic properties, J. Hydrol., 356, 147–162, https://doi.org/10.1016/j.jhydrol.2008.04.016, 2008.
Peters, A., Durner, W., and Wessolek, G.: Consistent parameter constraints for soil hydraulic functions, Adv. Water Resour., 34, 1352–1365, https://doi.org/10.1016/j.advwatres.2011.07.006, 2011.
Price, J. S.: Role and character of seasonal peat soil deformation on the hydrology of undisturbed and cutover peatlands, Water Resour. Res., 39, 1241, https://doi.org/10.1029/2002WR001302, 2003.
Price, J. S. and Schlotzhauer, S. M.: Importance of shrinkage and compression in determining water storage changes in peat: the case of a mined peatland, Hydrol. Process., 13, 2591–2601, 1999.
Price, J. S. and Whittington, P. N.: Water flow in Sphagnum hummocks: Mesocosm 836 measurements and modelling, J. Hydrol., 381, 333–340, 2010.
Price, J. S., Heathwaite, A. L., and Baird, A. J.: Hydrological processes in abandoned and restored peatlands: An overview of management approaches, Wetlands Ecol. Manage., 11, 65–83, 2003.
Price, J. S., Whittington, P. N., Elrick, D. E., Strack, M., Brunet, N., and Faux, E.: A method to determine unsaturated undecomposed Sphagnum moss, Soil Sci. Soc. Am. J., 72, 487–491, https://doi.org/10.2136/sssaj2007.0111N, 2008.
Price, J. S., Edwards, T. W. D., Yi, Y., and Whittington, P. N.: Physical and isotopic characterization of evaporation from Sphagnum moss, J. Hydrol., 369, 175–182, 2009.
Price, K. V., Storn, R. M., and Lampinen, J. A.: Differential Evolution – A Practical Approach to Global Optimization, Springer-Verlag, Berlin, Heidelberg, 2006.
Priesack, E. and Durner, W.: Closed-form expression for the multi-modal unsaturated conductivity function, Vadose Zone J., 5, 121–124, https://doi.org/10.2136/vzj2005.0066, 2006.
Qi, G., Michel, J.-C., Boivin, P., and Charpentier, S.: A Laboratory Device for Continual Measurement of Water Retention and Shrink/Swell Properties during Drying/Wetting Cycles, Hortscience, 46, 1298–1302, 2011.
Quinton, W. L., Hayashi, M., and Carey, S. K.: Peat hydraulic conductivity in cold regions and its relation to pore size and geometry, 22, 2829–2837, https://doi.org/10.1002/hyp.7027, 2008.
Quinton, W. L., Elliot, T. R., Price, J. S., Rezanezhad, F., and Heck, R. J.: Measuring physical and hydraulic properties of peat from X-ray tomography, Geoderma, 153, 269–277, 2009.
Rezanezhad, F., Quinton, W. L., Price, J. S., Elrick, D., Elliot, T. R., and Heck, R. J.: Examining the effect of pore size distribution and shape on flow through unsaturated peat using computed tomography, Hydrol. Earth Syst. Sci., 13, 1993–2002, https://doi.org/10.5194/hess-13-1993-2009, 2009.
Rezanezhad, F., Quinton, W. L., Price, J. S., Elliot, T. R., Elrick, D., and Shook, K. R.: Influence of pore size and geometry on peat unsaturated hydraulic conductivity computed from 3D computed tomography image analysis, Hydrol. Process., 24, 2983–2994, 2010.
Rezanezhad, F., Price, J. S., Quinton, W. L., Lennartz, B., Milojevic, T., and Van Cappellen, P.: Structure of peat soils and implications for water storage, flow and solute transport: A review update for geochemists, Chem. Geol., 429, 75–84, 2016.
Rydin, H. and Jeglum, J. K.: The Biology of Peatlands, 2nd Edn., OUP, Oxford, p. 400, 2016.
Saito, H., Šimůnek, J., and Mohanty, B. P.: Numerical analysis of coupled water, vapor, and heat transport in the Vadose Zone, Vadose Zone J., 5, 784–800, https://doi.org/10.2136/vzj2006.0007, 2006.
Schlotzhauer, S. M. and Price, J. S.: Soil water flow dynamics in a managed cutover peat field, Quebec: Field and laboratory investigations, Water Resour. Res., 35, 3675–3683, 1999.
Schwärzel, K., Šimůnek, J., Stoffregen, H., Wessolek, G., and van Genuchten, M. T.: Estimation of the unsaturated hydraulic conductivity of peat soils: Laboratory versus field data, Vadose Zone J., 5, 628–640, 2006.
Sherwood, J. H., Kettridge, N., Thompson, D. K., Morris, P. J., Silins, U., and Waddington, J. M.: Effect of drainage and wildfire on peat hydrophysical properties, Hydrol. Process., 27, 1866–1874, https://doi.org/10.1002/hyp.9820, 2013.
Šimůnek, J., van Genuchten, M. T., and Miroslav, Š.: Recent Developments and Applications of the HYDRUS Computer Software Packages, Vadose Zone J., 15, https://doi.org/10.2136/vzj2016.04.0033, 2016.
Sulman, B. N., Desai, A. R., Schroeder, N. M., Ricciuto, D., Barr, A., Richardson, A. D., Flanagan, L. B., Lafleur, P. M., Tian, H., Chen, G., Grant, R. F., Poulter, B., Verbeeck, H., Ciais, P., Ringeval, B., Baker, I. T., Schaefer, K., Luo, Y., and Weng, E.: Impact of hydrological variations on modeling of peatland CO2 fluxes: Results from the North American Carbon Program site synthesis, J. Geophys. Res., 117, G01031, https://doi.org/10.1029/2011JG001862, 2012.
Tokunaga, T. K.: Hydraulic properties of adsorbed water films in unsaturated porous media, Water Resour. Res., 45, W06415, https://doi.org/10.1029/2009WR007734, 2009.
Valat, B., Jouany, C., and Rivere, L. M.: Characterization of the wetting and properties of air-dried peats and composts, Soil Sci., 152, 100–107, 1991.
van Breemen, N.: How Sphagnum bogs down other plants, Tree, 10, 270–275, 1995.
van Genuchten, M. T.: Closed-form equation for predicting the hydraulic conductivity of unsaturated soils, Soil Sci. Soc. Am. J., 44, 892–898, 1980.
Vereecken, H., Kasteel, R., Vanderborght, J., and Harter, J.: Upscaling Hydraulic Properties and Soil Water Flow Processes in Heterogeneous Soils: A Review, Vadose Zone J., 6, 1–28, https://doi.org/10.2136/vzj2006.0055, 2007.
Weber, T. K. D., Iden, S. C., and Durner, W.: Unsaturated hydraulic properties of Sphagnum moss and peat reveal trimodal pore-size distributions, Water Resour. Res., 53, 415–434, https://doi.org/10.1002/2016WR019707, 2017a.
Weber, T. K. D., Gerling, L., Reineke, S., Weber, S., Durner, W., and Iden, S. C.: Robust inverse modeling of net ecosystem exchange in a mountainous peatland: influence of distributional assumptions on estimated parameters and total carbon fluxes, J. Adv. Model. Earth Syst., in review, 2017b.
Weller, U., Ippisch, O., Köhne, M., and Vogel, H.-J.: Direct measurement of unsaturated conductivity including hydraulic nonequilibrium and hysteresis, Vadose Zone J., 10, 654–661, https://doi.org/10.2136/vzj2010.0074, 2011.
Wendroth, O., Ehlers, W., Hopmans, J. W., Kage, H., Halbertsma, J., and Wösten, J. H. M.: Reevaluation of the Evaporation Method for Determining Hydraulic Functions in Unsaturated Soils, Soil Sci. Soc. Am. J., 57, 1436–1443, https://doi.org/10.2136/sssaj1993.03615995005700060007x, 1993.
Wu, Y. and Blodau, C.: PEATBOG: a biogeochemical model for analyzing coupled carbon and nitrogen dynamics in northern peatlands, Geosci. Model Dev., 6, 1173–1207, https://doi.org/10.5194/gmd-6-1173-2013, 2013.
Ye, M., Meyer, P. D., and Neuman, S. P.: On model selection criteria in multimodel analysis, Water Resour. Res., 44, W03428, https://doi.org/10.1029/2008WR006803, 2008.
Zurmühl, T. and Durner, W.: Determination of Parameters for Bimodal Hydraulic Functions by Inverse Modelling, Soil Sci. Soc. Am. J., 62, 874–880, https://doi.org/10.2136/sssaj1998.03615995006200040004x, 1998.