Richards equation
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Physics‐Informed Deep Neural Networks for Learning Parameters and Constitutive Relationships in Subsurface Flow Problems Open
We present a physics‐informed deep neural network (DNN) method for estimating hydraulic conductivity in saturated and unsaturated flows governed by Darcy's law. For saturated flow, we approximate hydraulic conductivity and head with two DN…
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Numerical Solution of Richards' Equation: A Review of Advances and Challenges Open
Core Ideas The numerical solution of Richards' equation remains challenging. Space/time discretization affects both computational effort and accuracy. Adaption of space and time discretizations produces benefits. Dissemination of codes and…
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A study on iterative methods for solving Richards’ equation Open
This work concerns linearization methods for efficiently solving the Richards` equation,a degenerate elliptic-parabolic equation which models flow in saturated/unsaturated porous media.The discretization of Richards` equation is based on b…
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Root zone soil moisture estimation with Random Forest Open
Accurate estimates of root zone soil moisture (RZSM) at relevant spatio-temporal scales are essential for many agricultural and hydrological applications. Applications of machine learning (ML) techniques to estimate root zone soil moisture…
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Parameterization of Root Water Uptake Models Considering Dynamic Root Distributions and Water Uptake Compensation Open
Core Ideas Parameters of different RWU models were optimized using data from a rhizotron facility. The same soil hydraulic properties were obtained for models considering RWU compensation. Feddes–Jarvis and Couvreur models predicted simila…
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Application of physics-informed neural networks to inverse problems in unsaturated groundwater flow Open
This paper investigates the application of Physics-Informed Neural Networks (PINNs) to inverse problems in unsaturated groundwater flow. PINNs are applied to the types of unsaturated groundwater flow problems modelled with the Richards par…
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Physics‐Informed Neural Networks With Monotonicity Constraints for Richardson‐Richards Equation: Estimation of Constitutive Relationships and Soil Water Flux Density From Volumetric Water Content Measurements Open
Water retention curves (WRCs) and hydraulic conductivity functions (HCFs) are critical soil‐specific characteristics necessary for modeling the movement of water in soils using the Richardson‐Richards equation (RRE). Well‐established labor…
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Coupling DSSAT and HYDRUS-1D for simulations of soil water dynamics in the soil-plant-atmosphere system Open
Accurate estimation of the soil water balance of the soil-plant-atmosphere system is key to determining the availability of water resources and their optimal management. Evapotranspiration and leaching are the main sinks of water from the …
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Heat and water transport in soils and across the soil‐atmosphere interface: 1. Theory and different model concepts Open
Evaporation is an important component of the soil water balance. It is composed of water flow and transport processes in a porous medium that are coupled with heat fluxes and free air flow. This work provides a comprehensive review of mode…
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Simulating ice layer formation under the presence of preferential flow in layered snowpacks Open
For physics-based snow cover models, simulating the formation of dense ice layers inside the snowpack has been a long-time challenge. Their formation is considered to be tightly coupled to the presence of preferential flow, which is assume…
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Forward and inverse modeling of water flow in unsaturated soils with discontinuous hydraulic conductivities using physics-informed neural networks with domain decomposition Open
Modeling water flow in unsaturated soils is vital for describing various hydrological and ecological phenomena. Soil water dynamics is described by well-established physical laws (Richardson–Richards equation – RRE). Solving the RRE is dif…
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Modelling liquid water transport in snow under rain-on-snow conditions – considering preferential flow Open
Rain on snow (ROS) has the potential to generate severe floods. Thus, precisely predicting the effect of an approaching ROS event on runoff formation is very important. Data analyses from past ROS events have shown that a snowpack experien…
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A vegetation‐focused soil‐plant‐atmospheric continuum model to study hydrodynamic soil‐plant water relations Open
A novel simple soil‐plant‐atmospheric continuum model that emphasizes the vegetation's role in controlling water transfer (v‐SPAC) has been developed in this study. The v‐SPAC model aims to incorporate both plant and soil hydrological meas…
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A Groundwater and Runoff Formulation for Weather and Climate Models Open
Soil moisture modifies the state of the atmosphere and thus plays a major role in the climate system. Its spatial distribution is strongly modulated by the underlying orography. Yet the vertical transport of soil water and especially the g…
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Machine Learning vs. Physics-Based Modeling for Real-Time Irrigation Management Open
Real-time monitoring of soil matric potential has now become a common practice for
\nprecision irrigation management. Some crops, such as cranberries, are susceptible
\nto both water and anoxic stresses. Excessive variations in soil matric…
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Analysis of plant root–induced preferential flow and pore-water pressure variation by a dual-permeability model Open
Vegetation can affect slope hydrology and stability via plant transpiration and induced matric suction. Previous work suggested that the presence of plant roots would induce preferential flow, and its effects may be more significant when t…
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Development and evaluation of a variably saturated flow model in the global E3SM Land Model (ELM) version 1.0 Open
Improving global-scale model representations of near-surface soil moisture and groundwater hydrology is important for accurately simulating terrestrial processes and predicting climate change effects on water resources. Most existing land …
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Advancing NASA’s AirMOSS P-Band Radar Root Zone Soil Moisture Retrieval Algorithm via Incorporation of Richards’ Equation Open
P-band radar remote sensing applied during the Airborne Microwave Observatory of Subcanopy and Subsurface (AirMOSS) mission has shown great potential for estimation of root zone soil moisture. When retrieving the soil moisture profile (SMP…
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Numerical solution of the Kirchhoff-transformed Richards equation for simulating variably saturated flow in heterogeneous layered porous media Open
A new numerical method was developed to accurately and efficiently compute a solution of the nonlinear Richards equation with a layered soil. In the proposed method, the Kirchhoff integral transformation was applied. However, in the Kirchh…
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The “good” Boussinesq equation : long-timeasymptotics Open
We consider the initial-value problem for the "good" Boussinesq equation on the line.Using inverse scattering techniques, the solution can be expressed in terms of the solution of a 3 × 3-matrix Riemann-Hilbert problem.We establish formula…
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Earthworms and tree roots: A model study of the effect of preferential flow paths on runoff generation and groundwater recharge in steep, saprolitic, tropical lowland catchments Open
Preferential flow paths (PFPs) affect the hydrological response of humid tropical catchments but have not received sufficient attention. We consider PFPs created by tree roots and earthworms in a near‐surface soil layer in steep, humid, tr…
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Prediction of soil evaporation measured with weighable lysimeters using the FAO Penman–Monteith method in combination with Richards’ equation Open
Multiannual data (2016–2018) from 12 weighed lysimeters (four soil types with textures ranging from sandy loam to silt loam, three replicates) of the TERENO SOILCan network were used to evaluate if evaporation ( E ) rates could be predicte…
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A New Simulation Framework for Soil–Root Interaction, Evaporation, Root Growth, and Solute Transport Open
Core Ideas We present a locally mass‐conservative flow, transport, and root–soil interaction model. We include a sustainable, flexible research software framework for plant‐scale model development. This is an improved model concept for flu…
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A hybrid analytical-numerical method for solving water flow equations in root hydraulic architectures Open
In this manuscript we propose a new method to calculate water flow and xylem water potential distribution in hydraulic architectures (such as root systems) of any complexity. It is based on the extension of the water flow equation analytic…
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Darcy, Forchheimer, Brinkman and Richards: classical hydromechanical equations and their significance in the light of the TPM Open
In hydromechanical applications, Darcy, Brinkman, Forchheimer and Richards equations play a central role when porous media flow under saturated and unsaturated conditions has to be investigated. While Darcy, Brinkman, Forchheimer and Richa…
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An analytical solution of Richards' equation providing the physical basis of SCS curve number method and its proportionality relationship Open
The empirical proportionality relationship, which indicates that the ratio of cumulative surface runoff and infiltration to their corresponding potentials are equal, is the basis of the extensively used Soil Conservation Service Curve Numb…
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Iterative schemes for surfactant transport in porous media Open
In this work, we consider the transport of a surfactant in variably saturated porous media. The water flow is modelled by the Richards equations and it is fully coupled with the transport equation for the surfactant. Three linearization te…
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Towards quantitative root hydraulic phenotyping: novel mathematical functions to calculate plant-scale hydraulic parameters from root system functional and structural traits Open
Predicting root water uptake and plant transpiration is crucial for managing plant irrigation and developing drought-tolerant root system ideotypes (i.e. ideal root systems). Today, three-dimensional structural functional models exist, whi…
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Alternative Model for Predicting Soil Hydraulic Conductivity Over the Complete Moisture Range Open
Considering film flow in the development of a soil hydraulic model has become a key method for improving model performance under dry conditions. With the considerable improvement in model performance, the trade‐off is often to increase the…
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Application of spreadsheet to estimate infiltration parameters Open
Infiltration is the process of flow of water into the ground through the soil surface. Soil water although contributes a negligible fraction of total water present on earth surface, but is of utmost importance for plant life. Estimation of…