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Artikel Jurnal
Stress Effects on Soil Freezing Characteristic Curve: Equipment Development and Experimental Results
The soil freezing characteristic curve (SFCC) defines the relationship between soil temperature and unfrozen water content. This curve is important for predicting water flow and heat conduction in frozen soils, as well as freezing heave and thawing settlement. So far, SFCCs reported in the…
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Artikel Jurnal
How Meaningful are Plot-Scale Observations and Simulations of Preferential Flow for Catchment Models?
Despite ubiquitous field observations of nonuniform flow processes, preferential flow paths are rarely considered in hydrological models, especially at catchment scale. In this study, we investigated the extent to which plot-scale observations of preferential flow paths are informative for…
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Artikel Jurnal
On the Information Content of Cosmic-Ray Neutron Data in the Inverse Estimation of Soil Hydraulic Properties
Observations of soil moisture content from remote sensing platforms can be used in conjunction with hydrological models to inversely estimate soil hydraulic properties (SHPs). In recent years, cosmic-ray neutron sensing (CRNS) has proven to be a reliable method for the estimation of area-average…
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Artikel Jurnal
Interplay between Molecular Diffusion and Advection during Solute Transport in Macroporous Media
Solute transport in soils is known to differ from solute transport in homogeneous porous media. Nonequilibrium processes, like those induced by the presence of macropores, can strongly influence the breakthrough of solute in soils. Breakthrough experiments and effective models are often combined to…
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Artikel Jurnal
Spectral Induced Polarization of Biochar in Variably Saturated Soil
Biochar is considered a promising soil amendment, but an effective method to detect and characterize the spatial distribution and temporal dynamics of biochar in soil is still missing. The aim of this study is to investigate the ability of the spectral induced polarization (SIP) method for the…
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Artikel Jurnal
Characterization of Gas Injection Flow Patterns Subject to Gravity and Viscous Forces
Gas movement in otherwise water-saturated porous media is complex and is important for a variety of applications. The interplay of gravity, capillary, and viscous forces influences the movement and resulting pattern of gas. To develop a better understanding of this competition among these forces…
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Artikel Jurnal
Testing a Water Redistribution Model in a Cracked Vertisol at Two Scales
Water is preferentially conducted away from the soil surface through large cracks formed in shrink–swell soils, which complicates our ability to calculate the partitioning of water into infiltration and runoff. Preferential flow paths affect the hydrology of a landscape but often are not included…
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Artikel Jurnal
Dye Tracers Reveal Potential Edge-Flow Effects in Undisturbed Lysimeters Sealed with Petrolatum
Undisturbed soil lysimeters are widely used to study water and solute transport. During or following lysimeter collection, it is common to implement measures aimed at limiting edge flow at the interface between the soil and the lysimeter casing. The objective of this study was to use dye tracers to…
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Artikel Jurnal
Influence of Stone Content on Soil Hydraulic Properties: Experimental Investigation and Test of Existing Model Concepts
Studying the role of gravel, stones, or rock fragments on effective soil hydraulic properties (SHPs) is crucial for understanding and predicting soil water processes such as evaporation, redistribution, and water and solute transport through soils containing significant amounts of coarse…
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Artikel Jurnal
Microhydrological Niches in Soils: How Mucilage and EPS Alter the Biophysical Properties of the Rhizosphere and Other Biological Hotspots
Plant roots and bacteria are capable of buffering erratic fluctuations of water content in their local soil environment by releasing a diverse, highly polymeric blend of substances (e.g. extracellular polymeric substances [EPS] and mucilage). Although this concept is well accepted, the physical…
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Artikel Jurnal
A Generalized Analytical Solution for Preferential Infiltration and Wetting
Macropores induce preferential flow in many soils, creating the need for parsimonious solutions to describe nonequilibrium infiltration and wetting processes. This study applied the Green–Ampt infiltration model within a dual-domain framework to distinguish water movement through the soil matrix…
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Artikel Jurnal
Modeling the Impact of Biopores on Root Growth and Root Water Uptake
Roots are known to use biopores as preferential growth pathways to overcome hard soil layers and access subsoil water resources. This study evaluates root–biopore interactions at the root-system scale under different soil physical and environmental conditions using a mechanistic simulation model…
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Artikel Jurnal
Quantifying Nitrate Leaching under Commercial Red Raspberry Using Passive Capillary Wick Samplers
Groundwater NO–N contamination in the Abbotsford-Sumas Aquifer in British Columbia, Canada, has been attributed primarily to NO–N leaching from red raspberry ( L.); however, direct estimates of NO–N leaching are lacking. This study quantified the magnitude and timing of NO–N leaching under a…
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Artikel Jurnal
Nutrient Leaching in Soil Affected by Fertilizer Application and Frozen Ground
Agricultural runoff containing P and N from drainage tiles contributes to nutrient loading in waterways, leading to downstream eutrophication. Recent studies suggest that nutrient losses through tile drains can be reduced if nutrients are applied in the subsurface. This study explored interactions…
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Artikel Jurnal
Observing Heterogeneous Unsaturated Flow at the Hillslope Scale Using Time-Lapse Electrical Resistivity Tomography
Understanding water partitioning and storage on mountain hillslopes is important for vadose zone hydrologic modeling, water balance calculations, and predicting landslides. Revealing the dynamics of unsaturated water movement through time remains challenging due to the scarcity of spatially…
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Artikel Jurnal
Assessment of Managed Aquifer Recharge Sites Using a New Geophysical Imaging Method
In many places around the world, much attention is focused on managed aquifer recharge (MAR) because of reduced groundwater levels due to droughts. To assess the suitability of a site for MAR, detailed three-dimensional (3D) information about the subsurface materials and their hydraulic properties…
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Artikel Jurnal
Viscous Flow Approach to “Pushing Out Old Water” from Undisturbed and Repacked Soil Columns
The application of bromide tracer in transient infiltration–drainage experiments on undisturbed and repacked soil columns revealed distinct delays of tracer front arrivals with respect to the wetting front arrivals. A viscous flow approach was matched to the flow data that resulted in the…
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Artikel Jurnal
Metals and Metalloid Removal by Colloidal Humic Acid–Goethite: Column Experiments and Geochemical Modeling
Reactive barriers are proposed to scavenge groundwater contaminants such as metals and arsenate. Their remediation capacity is commonly investigated with sorption data disregarding the complexity of the interactions among elements when faced with mixed contamination. This study was set up to…