Articles | Volume 20, issue 10
06 Oct 2016
Research article | 06 Oct 2016
Prediction of biopore- and matrix-dominated flow from X-ray CT-derived macropore network characteristics
Muhammad Naveed et al.
No articles found.
Ulrich Weller, Lukas Albrecht, Steffen Schlüter, and Hans-Jörg Vogel
SOIL, 8, 507–515,Short summary
Soil structure is of central importance for soil functions. It is, however, ill defined. With the increasing availability of X-ray CT scanners, more and more soils are scanned and an undisturbed image of the soil's structure is produced. Often, a qualitative description is all that is derived from these images. We provide now a web-based Soil Structure Library where these images can be evaluated in a standardized quantitative way and can be compared to a world-wide data set.
Lena Rohe, Bernd Apelt, Hans-Jörg Vogel, Reinhard Well, Gi-Mick Wu, and Steffen Schlüter
Biogeosciences, 18, 1185–1201,Short summary
Total denitrification, i.e. N2O and (N2O + N2) fluxes, of repacked soil cores were analysed for different combinations of soils and water contents. Prediction accuracy of (N2O + N2) fluxes was highest with combined proxies for oxygen demand (CO2 flux) and oxygen supply (anaerobic soil volume fraction). Knowledge of denitrification completeness (product ratio) improved N2O predictions. Substitutions with cheaper proxies (soil organic matter, empirical diffusivity) reduced prediction accuracy.
Jannis Groh, Jan Vanderborght, Thomas Pütz, Hans-Jörg Vogel, Ralf Gründling, Holger Rupp, Mehdi Rahmati, Michael Sommer, Harry Vereecken, and Horst H. Gerke
Hydrol. Earth Syst. Sci., 24, 1211–1225,
Steffen Schlüter, Jan Zawallich, Hans-Jörg Vogel, and Peter Dörsch
Biogeosciences, 16, 3665–3678,Short summary
A combination of gas chromatography and X-ray CT reveals the microscale processes that govern soil respiration. Aerobic and anaerobic respiration in microbial hotspots depends not only on the quality and quantity of soil organic matter, but also on the spatial distribution of hotspots. Denitrification kinetics are mainly governed by hotspot architecture due to local competition for oxygen during growth. Cumulative behavior is mainly governed by water saturation due to the overall supply with O2.
Hans-Jörg Vogel, Stephan Bartke, Katrin Daedlow, Katharina Helming, Ingrid Kögel-Knabner, Birgit Lang, Eva Rabot, David Russell, Bastian Stößel, Ulrich Weller, Martin Wiesmeier, and Ute Wollschläger
SOIL, 4, 83–92,Short summary
This paper deals with the importance of soil for our terrestrial environment and the need to predict the impact of soil management on the multitude of functions that soil provides. We suggest to consider soil as a self-organized complex system and provide a concept of how this could be achieved. This includes how soil research, currently fragmented into a number of more or less disjunct disciplines, may be integrated to substantially contribute to a science-based evaluation of soil functions.
S. Schlüter, F. Leuther, S. Vogler, and H.-J. Vogel
Solid Earth, 7, 129–140,Short summary
A new protocol for digital volume correlation facilitates detailed insights into internal deformation of soil. Structure deformation during centrifugation is revealed by comparing X-ray CT images before and after centrifugation. Quantitative image analysis reveals that soil structure changes are driven by soil shrinkage due to drying and soil compaction due to compression.
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,
Related subject area
Subject: Vadose Zone Hydrology | Techniques and Approaches: Modelling approachesStepping beyond perfectly mixed conditions in soil hydrological modelling using a Lagrangian approachUsing machine learning to predict optimal electromagnetic induction instrument configurations for characterizing the shallow subsurfaceGravity as a tool to improve the hydrologic mass budget in karstic areasA scaling procedure for straightforward computation of sorptivityFrom hydraulic root architecture models to macroscopic representations of root hydraulics in soil water flow and land surface modelsSimulated 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 modelingAssessing the dynamics of soil salinity with time-lapse inversion of electromagnetic data guided by hydrological modellingSimulation of reactive solute transport in the critical zone: a Lagrangian model for transient flow and preferential transportInvestigating the impact of exit effects on solute transport in macroporous mediaComparison of root water uptake models in simulating CO2 and H2O fluxes and growth of wheatUnderstanding the mass, momentum, and energy transfer in the frozen soil with three levels of model complexitiesA field-validated surrogate crop model for predicting root-zone moisture and salt content in regions with shallow groundwaterCharacterizing uncertainty in the hydraulic parameters of oil sands mine reclamation covers and its influence on water balance predictionsSimulating preferential soil water flow and tracer transport using the Lagrangian Soil Water and Solute Transport ModelAssessment of simulated soil moisture from WRF Noah, Noah-MP, and CLM land surface schemes for landslide hazard applicationEfficient estimation of effective hydraulic properties of stratal undulating surface layer using time-lapse multi-channel GPRPartitioning snowmelt and rainfall in the critical zone: effects of climate type and soil propertiesA unique vadose zone model for shallow aquifers: the Hetao irrigation district, ChinaModelling of shallow water table dynamics using conceptual and physically based integrated surface-water–groundwater hydrologic modelsCapturing soil-water and groundwater interactions with an iterative feedback coupling scheme: new HYDRUS package for MODFLOWCaffeine vs. carbamazepine as indicators of wastewater pollution in a karst aquiferPredicting the soil water retention curve from the particle size distribution based on a pore space geometry containing slit-shaped spacesTechnical note: Saturated hydraulic conductivity and textural heterogeneity of soilsWater ages in the critical zone of long-term experimental sites in northern latitudesEcohydrological particle model based on representative domainsImpact of capillary rise and recirculation on simulated crop yieldsSoil hydraulic material properties and layered architecture from time-lapse GPRRoot growth, water uptake, and sap flow of winter wheat in response to different soil water conditionsUsing lagged dependence to identify (de)coupled surface and subsurface soil moisture valuesShallow water table effects on water, sediment, and pesticide transport in vegetative filter strips – Part 1: nonuniform infiltration and soil water redistributionShallow water table effects on water, sediment, and pesticide transport in vegetative filter strips – Part 2: model coupling, application, factor importance, and uncertaintyA pore-size classification for peat bogs derived from unsaturated hydraulic propertiesMonitoring and modeling infiltration–recharge dynamics of managed aquifer recharge with desalinated seawaterEffect of unrepresented model errors on estimated soil hydraulic material propertiesSaturated hydraulic conductivity model computed from bimodal water retention curves for a range of New Zealand soilsRoss scheme, Newton–Raphson iterative methods and time-stepping strategies for solving the mixed form of Richards' equationFeasibility analysis of using inverse modeling for estimating field-scale evapotranspiration in maize and soybean fields from soil water content monitoring networksA case study of field-scale maize irrigation patterns in western Nebraska: implications for water managers and recommendations for hyper-resolution land surface modelingBenchmarking test of empirical root water uptake modelsiCRESTRIGRS: a coupled modeling system for cascading flood–landslide disaster forecastingEnKF with closed-eye period – towards a consistent aggregation of information in soil hydrologyA Lagrangian model for soil water dynamics during rainfall-driven conditionsQuantifying shallow subsurface water and heat dynamics using coupled hydrological-thermal-geophysical inversionStem–root flow effect on soil–atmosphere interactions and uncertainty assessmentsThe effect of different evapotranspiration methods on portraying soil water dynamics and ET partitioning in a semi-arid environment in Northwest ChinaSensitivity of water stress in a two-layered sandy grassland soil to variations in groundwater depth and soil hydraulic parametersUnderstanding NMR relaxometry of partially water-saturated rocksEstimating flow and transport parameters in the unsaturated zone with pore water stable isotopesEstimation of temporal and spatial variations in groundwater recharge in unconfined sand aquifers using Scots pine inventories
Alexander Sternagel, Ralf Loritz, Brian Berkowitz, and Erwin Zehe
Hydrol. Earth Syst. Sci., 26, 1615–1629,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,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,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,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,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,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,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,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,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,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,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,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,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,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,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,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,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,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,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,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,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,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,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,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,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,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,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,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,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,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,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,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,
Yonatan Ganot, Ran Holtzman, Noam Weisbrod, Ido Nitzan, Yoram Katz, and Daniel Kurtzman
Hydrol. Earth Syst. Sci., 21, 4479–4493,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,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,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,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,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,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,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,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,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.
Erwin Zehe and Conrad Jackisch
Hydrol. Earth Syst. Sci., 20, 3511–3526,
Anh Phuong Tran, Baptiste Dafflon, Susan S. Hubbard, Michael B. Kowalsky, Philip Long, Tetsu K. Tokunaga, and Kenneth H. Williams
Hydrol. Earth Syst. Sci., 20, 3477–3491,Short summary
Quantifying water and heat fluxes in the shallow subsurface is particularly important due to their strong control on recharge, evaporation and biogeochemical processes. This study developed and tested a new inversion scheme to estimate subsurface hydro-thermal parameters by joint using different hydrological, thermal and geophysical data. It is especially useful for the increasing number of studies that are taking advantage of autonomously collected measurements to explore ecosystem dynamics.
Tzu-Hsien Kuo, Jen-Ping Chen, and Yongkang Xue
Hydrol. Earth Syst. Sci., 20, 1509–1522,Short summary
The stem-root flow mechanism was parameterized and incorporated into the Simplified Simple Biosphere model to analyze its impact on soil moisture and land-atmospheric interactions. By testing against the Lien Hua Chih (Taiwan) and HAPEX-Mobilhy (France) measurements, the model shows that stem-root flow reduced the top-soil moisture content and moistened the deeper soil layers. Such soil moisture redistribution results in significant changes in heat flux exchange between land and atmosphere.
Lianyu Yu, Yijian Zeng, Zhongbo Su, Huanjie Cai, and Zhen Zheng
Hydrol. Earth Syst. Sci., 20, 975–990,Short summary
The coupled water vapor and heat transport model using two different ET (ETdir, ETind) methods varied concerning the simulation of soil moisture and ET components, while agreed well for the simulation of soil temperature. Considering aerodynamic and surface resistance terms improved the ETdir method regarding simulating soil evaporation, especially after irrigation. The interactive effect of crop growth parameters with changing environment played an important role in estimating ET components.
M. Rezaei, P. Seuntjens, I. Joris, W. Boënne, S. Van Hoey, P. Campling, and W. M. Cornelis
Hydrol. Earth Syst. Sci., 20, 487–503,Short summary
The sensitivity of the combined model (LINGRA-N and HYDRUS-1D) to hydraulic parameters, water stress, crop yield and lower boundary conditions was assessed. We showed that it is sufficient to estimate limited amount of key parameters in optimization strategies. A combined modelling approach could increase water use efficiency (12–22.5 %) and yield (5–7%) by changing irrigation scheduling. Result calls for taking into account weather forecast and soil water content data in precision agriculture.
O. Mohnke, R. Jorand, C. Nordlund, and N. Klitzsch
Hydrol. Earth Syst. Sci., 19, 2763–2773,
M. Sprenger, T. H. M. Volkmann, T. Blume, and M. Weiler
Hydrol. Earth Syst. Sci., 19, 2617–2635,Short summary
We present a novel approach that includes information about the pore water stable isotopic composition in inverse model approaches to estimate soil hydraulic parameters. Different approaches are presented and their adequacy regarding the model efficiency, realism and parameter identifiability are discussed. The advantages of the new approach are shown by an application of the inverse estimated parameters to infer the water balance and the transit time for three different study sites.
P. Ala-aho, P. M. Rossi, and B. Kløve
Hydrol. Earth Syst. Sci., 19, 1961–1976,Short summary
We present a novel simulation method for estimating spatially distributed and transient groundwater recharge in unconfined sandy aquifers. The approach uses field data for the most important parameters affecting groundwater recharge and accounts for parameter uncertainty. The results show that tree canopy cover is the most important factor in controlling groundwater recharge at our study area. Tree canopy is thinned by forestry, which may lead to a significant increase of groundwater recharge.
Ahuja, L. R., Naney, J. W., Green, R. E., and Nielsen, D. R.: Macroporosity to characterize spatial variability of hydraulic conductivity and effects of land management, Soil Sci. Soc. Am. J., 48, 699–702, 1984.
Bouma, J.: Comments on micro- meso- and macroporosity of soil, Soil Sci. Soc. Am. J., 45, 1244–1245, 1981.
Buckingham, E.: Contributions to our knowledge of the aerations of soils. Bur. Soil Bull. 25. US Gov. Print. Office, Washington, DC, 1904.
Chamindu Deepagoda, T. K. K., Moldrup, P., de Jonge, L. W., Kawamoto, K., and Komatsu, T.: Density-corrected models for gas diffusivity and air permeability in unsaturated soil, Vadose Zone J., 10, 226–238, 2011.
Chen, C. W., Luo, J., and Parker, K. J.: Image segmentation via adaptive K-mean clustering and knowledge-based morphological operations with biomedical applications. IEEE T. Image Process., 7, 1673–1683, 1998.
Cosby, B. J., Hornberger, G. M., Clapp, R. B., and Ginn, T. R.: A statistical exploration of the relationships of soil moisture characteristics to the physical properties of soils, Water Resour. Res., 20, 682–690, 1984.
de Jonge, L. W., Moldrup, P., Rubaek, G. H., Schelde, K., and Djurhuus, J.: Particle leaching and particle-facilitated transport of phosphorus at field scale, Vadose Zone J., 3, 462–470, 2004.
Dougherty, R. and Kunzelmann, K.: Computing local thickness of 3D structures with Image J, Microsc. Microanal., 13, 1678–1679, 2007.
Elliot, T. R., Reynolds, W. D., and Heck, R. J.: Use of existing pore models and X-ray computed tomography to predict saturated soil hydraulic conductivity, Geoderma, 156, 133–142, 2010.
Feldkamp, L. A., Davis, L. C., and Kress, J. W.: Practical cone-beam algorithm, J. Opt. Soc. Am., 1, 612–619, 1984.
Fox, G. A., Malone, R., Sabbagh, G. J., and Rojas, K.: Interrelationship of macropores and subsurface drainage for conservative tracer and pesticide transport, J. Environ. Qual., 33, 2281–2289, 2004.
Geological Survey of Denmark and Greenland: Digitalt kort over Danmarks jordarter 1 : 200000; GEUS rapport 1999/47, Geological Survey of Denmark and Greenland, Copenhagen, Denmark, 1999 (in Danish).
Gonzalez-Sosa, E., Braud, I., Dehotin, J., Lassabatere, L., Angulo-Jaramillo, R., Lagouy, M., Branger, F., Jacqueminet, C., Kermadi, S., and Michel, K.: Impact of land use on the hydraulic properties of the topsoil in a small French catchment, Hydrol. Process., 24, 2382–2399, 2010.
Hu, W., Shao, M. A., and Si, B. C.: Seasonal changes in surface bulk density and saturated hydraulic conductivity of natural landscapes, Eur. J. Soil Sci., 63, 820–830, 2012.
Hu, Y., Feng, J., Yang, T., and Wang, C.: A new method to characterize the spatial structure of soil macropore networks in effects of cultivation using computed tomography, Hydrol. Process., 28, 3419–3431, 2014.
Iassonov, P. and Tuller, M.: Application of segmentation for correction of intensity bias in X-ray computed tomography images, Vadose Zone J., 9, 187–191, 2010.
Iassonov, P., Gebrenegus, T., and Tuller, M.: Segmentation of X-ray computed tomography images of porous materials: A crucial step for characterization and quantitative analysis of pore structures, Water Resour. Res., 45, W09415, https://doi.org/10.1029/2009WR008087, 2009.
Iqbal, J., Thomasson, J. A., Jenkins, J. N., Owens, P. R., and Whisler, F. D.: Spatial variability analysis of soil physical properties of alluvial soils, Soil Sci. Soc. Am. J., 69, 1338–1350, 2005.
Iversen, B. V., Schjønning, P., Poulsen, T. G., and Moldrup, P.: In situ, on-site and laboratory measurements of soil air permeability: Boundary conditions and measurement scale, Soil Sci., 166, 97–106, 2001.
Iversen, B. V., Børgesen, C. D., Lægdsmand, M., Greve, M. H., Heckrath, G., and Kjærgaard, C.: Risk predicting of macropore flow using pedotransfer functions, textural maps, and modeling, Vadose Zone J., 10, 1185–1195, 2011.
Jarvis, N., Koestel, J., Messing, I., Moeys, J., and Lindahl, A.: Influence of soil, land use and climatic factors on the hydraulic conductivity of soil, Hydrol. Earth Syst. Sci., 17, 5185–5195, https://doi.org/10.5194/hess-17-5185-2013, 2013.
Jarvis, N. J.: A review of non-equilibrium water flow and solute transport in soil macropores: Principles, controlling factors and consequences for water quality, Eur. J. Soil Sci., 58, 523–546, 2007.
Jarvis, N. J., Moeys, J., Hollis, J. M., Reichenberger, S., Lindahl, A. M. L., and Dubus, I. G.: A conceptual model of soil susceptibility to macropore flow, Vadose Zone J., 8, 902–910, 2009.
Jassogne, L., McNeill, A., and Chittleborough, D.: 3D visualization and analysis of macro- and meso-porosity of the upper horizons of sodic, texture-contrast soil, Eur. J. Soil Sci., 58, 589–598, 2007.
Katuwal, S., Nørgaard, T., Moldrup, P., Lamandé, M., Wildenschild, D., and de Jonge, L. W.: Linking air and water transport in intact soils to macropore characteristics inferred from X-ray computed tomography, Geoderma, 237–238, 9–20, 2015.
Kawamoto, K., Moldrup, P., Schjønning, P., Iversen, B. V., Komatsu, T., and Rolston, D. E.: Gas transport parameters in the vadose zone: Development and test of power-law models for air permeability, Vadose Zone J., 5, 1205–1215, 2006.
Klute, A. and Dirksen, C.: Hydraulic conductivity and diffusivity: Laboratory methods. In Methods of Soil Analysis, Part 1, 2nd Edn. Physical and Mineralogical Methods, edited by: Klute, A., ASA-SSSA, Madison, WI, 687–734, 1986.
Kulkarni, R., Tuller, M., Fink, W., and Wildenschild, D.: Three-dimensional multiphase segmentation of X-ray CT data of porous materials using a Bayesian Markov random field framework, Vadose Zone J., 11, https://doi.org/10.2136/vzj2011.0082, 2012.
Larsbo, M., Koestel, J., and Jarvis, N.: Relations between macropore network characteristics and the degree of preferential solute transport, Hydrol. Earth Syst. Sci., 18, 5255–5269, https://doi.org/10.5194/hess-18-5255-2014, 2014.
Lilly, A., Nemes, A., Rawls, W. J., and Pachepsky, Y. A.: Probabilistic approach to the identification of input variables to estimate hydraulic conductivity, Soil Sci. Soc. Am. J., 72, 16–24, 2008.
Luo, L., Lin, H., and Schmidt, J.: Quantitative relationships between soil macropore characteristics and preferential flow and transport, Soil Sci. Soc. Am. J., 74, 1929–1937, 2010.
Moldrup, P., Poulsen, T. G., Schjønning, P., Olsen, T., and Yamaguchi, T.: Gas permeability in undisturbed soils: Measurements and predictive models, Soil Sci., 163, 180–189, 1998.
Moldrup, P., Olesen, T., Gamst, J., Schjønning, P., Yamaguchi, T., and Rolston, D. E.: Predicting the gas diffusion coefficient in repacked soil: Water induced linear reduction model, Soil Sci. Soc. Am. J., 64, 1588–1594, 2000.
Moustafa, M. M.: A geostatistical approach to optimize the determination of saturated hydraulic conductivity for large-scale subsurface drainage design in Egypt, Agr. Water Manage., 42, 291–312, 2000.
Naveed, M.: Revealing soil architecture and quality: Linking state-of-the-art soil biophysicochemical measurements, visualizations, and simulations, PhD thesis, Aarhus University, Aarhus, 2014.
Naveed, M., Moldrup, P., Arthur, E., Wildenschild, D., Eden, M., Lamandé, M., Vogel, H.-J., and de Jonge, L. W.: Revealing soil structure and functional macroporosity along a clay gradient using X-ray computed tomography, Soil Sci. Soc. Am. J., 77, 403–411, 2013.
Naveed, M., Moldrup, P., Arthur, E., Holmstrup, M., Nicolaisen, M., Tuller, M., Herath, L., Hamamoto, S., Kawamoto, K., Komatsu, T., Vogel, H.-J., and de Jonge, L. W.: Simultaneous Loss of Soil Biodiversity and Functions Along a Copper Contamination Gradient: When Soil Goes to Sleep, Soil Sci. Soc. Am. J., 78, 1239–1250, 2014a.
Naveed, M., Moldrup, P., Vogel, H.-J., Lamandé, M., Wildenschild, D., Tuller, M., and de Jonge, L.W.: Impact of long-term fertilization practice on soil structure evolution, Geoderma, 217–218, 181–189, 2014b.
Norgaard, T., Moldrup, P., Olesen, P., Vendelboe, A. L., Iversen, B. V., Greve, M. H., Kjaer, J., and de Jonge, L. W.: Comparative mapping of soil physical-chemical and structural parameters at field scale to identify zones of enhanced leaching risk, J. Environ. Qual., 42, 271–283, 2013.
Paradelo, M., Moldrup, P., Arthur, E., Naveed, M., Holmstrup, M., López-Periago, J. E., and de Jonge, L. W.: Effects of Past Copper Contamination and Soil Structure on Copper Leaching from Soil, J. Environ. Qual., 42, 1852–1862, 2013.
Pérèsa, G., Bellidoa, A., Curmib, P., Marmonierc, P., and Cluzeaua, D.: Relationships between earthworm communities and burrow numbers under different land use systems, Pedobiologia, 54, 37–44, 2012.
Quinton, W. L., Hayashi, M., and Carey, S. K.: Peat hydraulic conductivity in cold regions and its relation to pore size and geometry, Hydrol. Process., 22, 2829–2837, 2008.
Raczkowski, C. W., Mueller, J. P., Busscher, W. J., Bell, M. C., and McGraw, M. L.: Soil physical properties of agricultural systems in a large-scale study, Soil Till. Res., 119, 50–59, 2012.
Rasband, W. S.: ImageJ, U.S. National Institutes of Health, Bethesda, Maryland, USA, http://imagej.nih.gov/ij/ (last access: 4 October 2016), 1997–2016.
Rawls, W. J., Gimenez, D., and Grossman, R.: Use of soil texture, bulk density and slope of the water retention curve to predict saturated hydraulic conductivity, T. ASAE, 41, 983–988, 1998.
Revil, A. and Cathles, L. M.: Permeability of shaly sands, Water Resour. Res., 35, 651–662, 1999.
Schaap, M. G., Leij, F. L., and van Genuchten, M. T.: Rosetta: A computer program for estimating soil hydraulic parameters with hierarchical pedotransfer functions, J. Hydrol., 251, 163–176, 2001.
Schjønning, P., Eden, M., Moldrup, P., and de Jonge, L. W.: Two-chamber, two-gas and one-chamber, one-gas methods for measuring the soil-gas diffusion coefficient: Validation and inter-calibration, Soil Sci. Soc. Am. J., 77, 729–744, 2013.
Sharma, P., Shukla, M. K., and Mexal, J. G.: Spatial variability of soil properties in agricultural fields of Southern New Mexico, Soil Sci., 176, 288–302, 2011.
Tuller, M., Kulkarni, R., and Fink, W.: Segmentation of X-ray CT data of porous materials: A review of global and locally adaptive algorithms, edited by: Anderson, S. H. and Hopmans, J. W., Soil–water–root processes: Advances in tomography and imaging, SSSA Spec. Publ. 61. SSSA, Madison, WI, 157–182, 2013.
USDA-NRCS Web Soil Survey 3.2: available at: http://websoilsurvey.nrcs.usda.gov/app/WebSoilSurvey.aspx (last access: 29 September 2016), 2010.
Vereecken, H., Maes, J., Feyen, J., and Darius, P.: Estimating the soil moisture retention characteristic from texture, bulk density, and carbon content, Soil Sci, 148, 389–403, 1989.
Vereecken, H., Weynants, M., Javaux, M., Pachepsky, Y., Schaap, M. G., and van Genuchten, M. T.: Using pedotransfer functions to estimate the van Genuchten-Mualem soil hydraulic properties: a review, Vadose Zone J., 9, 795–820, 2010.
Vogel, H.-J.: A numerical experiment on pore size, pore connectivity, water retention, permeability, and solute transport using network models, Eur. J. Soil Sci., 51, 99–105, 2000.
Vogel, H.-J., Weller, U., and Schlüter, S.: Quantification of soil structure based on Minkowski functions, Comput. Geosci., 36, 1236–1245, 2010.
Wang, Y., Shao, M., Liu, Z., and Horton, R.: Regional-scale variation and distribution patterns of soil saturated hydraulic conductivities in surface and subsurface layers in the loessial soils of China, J. Hydrol., 487, 13–23, 2013.
Weynants, M., Vereecken, H., and Javaux, M.: Revisiting Vereecken pedotransfer functions: Introducing a closed-form hydraulic model, Vadose Zone J., 8, 86–95, 2009.
Wösten, J. H. M., Lilly, A., Nemes, A., and Bas, C. L.: Development and use of a database of hydraulic properties of European soils, Geoderma, 90, 169–185, 1999.
Wildenschild, D. and Sheppard, A.: X-ray imaging and analysis techniques for quantifying pore-scale structure and processes in subsurface porous medium systems, Adv. Water Resour., 51, 217–246, 2013.
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.
Quantification of rapid flow of water and associated transport of contaminants through large...