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Artikel Jurnal
Modeling Soil Water Retention Curves in the Dry Range Using the Hygroscopic Water Content
Accurate information on the dry end (matric potential less than −1500 kPa) of soil water retention curves (SWRCs) is crucial for studying water vapor transport and evaporation in soils. The objectives of this study were to assess the potential of the Oswin model for describing the water adsorption…
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Artikel Jurnal
Modeling Subsurface Hillslope Runoff Dominated by Preferential Flow: One‐ vs. Two‐Dimensional Approximation
Shallow saturated subsurface flow, frequently observed on hillslopes of headwater catchments in humid temperate climates, often dominates hydrologic responses of the catchments to major rainfall events. Typically, these responses are significantly affected by the presence of preferential flow…
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Artikel Jurnal
A Screening Tool for Delineating Subregions of Steady Recharge within Groundwater Models
We have developed a screening method for simplifying groundwater models by delineating areas within the domain that can be represented using steady‐state groundwater recharge. The screening method is based on an analytical solution for the damping of sinusoidal infiltration variations in…
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Artikel Jurnal
Numerical Study of Prepolarized Surface Nuclear Magnetic Resonance in the Vadose Zone
Surface nuclear magnetic resonance (SNMR) is a geophysical technique for water exploration in the shallow subsurface. To investigate the vadose zone, it is necessary to increase the method sensitivity; therefore we developed a new approach for SNMR experiments. Adapted from laboratory applications…
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Artikel Jurnal
A Reevaluation of Time Domain Reflectometry Propagation Time Determination in Soils
Time domain reflectometry (TDR) is an established method for the determination of apparent dielectric permittivity and water content in soils. Using current waveform interpretation procedures, signal attenuation and variation in dielectric media properties along the transmission line can…
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Artikel Jurnal
Soil Hydraulic Parameters and Surface Soil Moisture of a Tilled Bare Soil Plot Inversely Derived from L‐Band Brightness Temperatures
We coupled a radiative transfer model and a soil hydrologic model (HYDRUS 1D) with an optimization routine to derive soil hydraulic parameters, surface roughness, and soil moisture of a tilled bare soil plot using measured brightness temperatures at 1.4 GHz (L‐band), rainfall, and potential soil…
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Artikel Jurnal
Sensitivity of Vadose Zone Water Fluxes to Climate Shifts in Arid Settings
In arid regions, groundwater resources are prone to depletion due to excessive water use and little recharge potential. Especially in sand dune areas, groundwater recharge is highly dependent on vadose zone properties and corresponding water fluxes. Nevertheless, vadose zone water fluxes under arid…
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Artikel Jurnal
Numerical Modeling of Gas Flow in the Suncor Coke Stockpile Covers
The occurrence of thermally driven convective air flow within waste rock or natural soil profiles has been well established; however, the potential impact that convective air flow may have on water storage within reclamation soil covers has not been previously explored. We conducted a numerical…
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Artikel Jurnal
Integrated Dynamic Modeling of Contaminant Fate and Transport within a Soil–Plant System
Contaminants found in the soil and in the atmosphere frequently find their way into plants. Because plants are at the bottom of the food chain, analysis of this pathway contributes to health risk assessment studies. On the other hand, plants that exist at a contaminated site have a potential effect…
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Artikel Jurnal
Evaporation from Porous Media in the Presence of a Water Table
Evaporation from porous media in the presence of a water table is influenced by the water table depth and the hydraulic characteristics of the medium, among other factors. For shallow water tables, the upward capillary liquid flow maintains continuous liquid pathways connecting the water table to…
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Artikel Jurnal
Uncertainty in Pesticide Monitoring Using Suction Cups: Evidence from Numerical Simulations
Knowledge of the spatial and temporal distribution of pesticide concentrations is essential for pesticide registration. In field experiments performed during the registration procedure, suctions cups are widely used to monitor the evolution of pesticide leaching over time and to calculate the mean…
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Artikel Jurnal
Estimation of Unsaturated Soil Hydraulic Parameters Using the Ensemble Kalman Filter
The parameters of soil hydraulic functions are essential to the accurate simulation of soil moisture based on the Richards equation. Optimal values of these parameters can be calibrated by inverse modeling, in which the incomplete consideration of various errors may influence the parameter…
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Artikel Jurnal
Transport and Deposition of Variably Charged Soil Colloids in Saturated Porous Media
A series of column experiments was conducted to investigate the transport and deposition of variably charged colloids in saturated porous media. Soil colloids with diameters
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Artikel Jurnal
Risk Predicting of Macropore Flow using Pedotransfer Functions, Textural Maps, and Modeling
Leaching of P to tile drains by colloid‐facilitated transport in macropores is an important pathway for P loss in structured soils. Macropore flow is the main transport route for many organic and inorganic pollutants, but macropore flow cannot currently be reliably predicted. The objectives of this…
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Artikel Jurnal
Macroscopic Evidence of Sources of Particles for Facilitated Transport during Intensive Rain
Particulate transport of pesticides, heavy metals, and phosphate in soil is of interest when evaluating water contamination risk; however, researchers differ in their view of how and where the contaminated particles are mobilized. The main line of thought is that the particles originate in the…
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Artikel Jurnal
Drainage under Nonequilibrium Conditions: Exploring Wettability and Dynamic Contact Angle Effects Using Bundle‐Of‐Tubes Simulations
Numerical simulators often assume that equilibrium capillary pressure–saturation conditions are maintained as changes in fluid saturation are taking place; however, equilibrium conditions may not be maintained in all circumstances. An alternative approach is to describe a nonequilibrium difference…
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Pore‐Scale Investigation of Colloid Retention and Mobilization in the Presence of a Moving Air–Water Interface
A review of current literature shows that considerable uncertainty exists concerning the role of the air–water interface (AWI) in colloid transport in unsaturated porous media. This study aimed to elucidate the mechanisms of colloid mobilization and retention at the AWI in a model dynamic system at…
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Artikel Jurnal
Flow Processes in the Dry Regime: The Effect on Capillary Barrier Performance
Engineered capillary barriers typically consist of two layers of granular materials designed so that the contrast in material hydraulic properties and sloping interface retain infiltrating water in the upper layer. We conducted two benchtop capillary barrier experiments, followed by interpretation…