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Artikel Jurnal
Challenges with effective representations of heterogeneity in soil hydrology based on local water content measurements
Abstract The description of soil water movement at the field scale requires soil hydraulic material properties. These cannot be measured directly and exhibit an intrinsic multiscale heterogeneity. The estimation of soil hydraulic properties through inverse modeling or data assimilation requires…
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Artikel Jurnal
Carbon turnover and microbial activity in an artificial soil under imposed cyclic drainage and imbibition
Abstract Water table fluctuations generate temporally and spatially dynamic physicochemical conditions that drive biogeochemical hot spots and hot moments in the vadose zone. However, their role in the cycling of soil C remains poorly known. Here, we present results from unvegetated column…
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Artikel Jurnal
Field evaluation of portable soil water content sensors in a sandy loam
Abstract Ground observations are critical in the validation of soil water content (SWC) estimates from both satellites and land surface models. Portable SWC sensors provide useful information to determine the amount of SWC in the topsoil layer for various applications; however, these probes are not…
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Artikel Jurnal
Calibration, measurement, and characterization of soil moisture dynamics in a central Amazonian tropical forest
Abstract Soil moisture plays a key role in hydrological, biogeochemical, and energy budgets of terrestrial ecosystems. Accurate soil moisture measurements in remote ecosystems such as the Amazon are difficult and limited because of logistical constraints. Time domain reflectometry (TDR) sensors are…
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Artikel Jurnal
Simulating future salinity dynamics in a coastal marshland under different climate scenarios
Abstract Salinization is a well‐known problem in agricultural areas worldwide. In the last 20–30 yr, rising salinity in the upper, unconfined aquifer has been observed in the Freepsumer Meer, a grassland near the German North Sea coast. For investigating long‐term development of salinity and water…
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Artikel Jurnal
Combining visible near‐infrared spectroscopy and water vapor sorption for soil specific surface area estimation
Abstract The soil specific surface area (SSA) is a fundamental property governing a range of soil processes relevant to engineering, environmental, and agricultural applications. A method for SSA determination based on a combination of visible near‐infrared spectroscopy (vis‐NIRS) and vapor…
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Artikel Jurnal
Water‐dispersible nanocolloids and higher temperatures promote the release of carbon from riparian soil
Abstract Increasing temperatures in alpine regions accompanied by glacial retreat is occurring rapidly due to climate change. This may affect riparian soils by increasing weathering rates, resulting in greater organic carbon (OC) release to rivers via movement of iron‐containing colloids and…
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Artikel Jurnal
BEST-2K Method for Characterizing Dual-Permeability Unsaturated Soils with Ponded and Tension Infiltrometers
This study presents a new method (BEST-2K) that extends the existing BEST methods for use in characterizing the water retention and hydraulic conductivity functions of matrix and fast-flow regions in dual-permeability soils. BEST-2K requires input information from two water infiltration experiments…
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Artikel Jurnal
Simulation of Soil Freezing and Thawing for Different Groundwater Table Depths
During freeze–thaw periods, the transformation between phreatic water and soil water will change the soil hydrothermal properties and affect the soil freezing and thawing in shallow groundwater areas. The purpose of this study was to determine the effect of four different groundwater table depths…
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Artikel Jurnal
Influences of Macropores on Infiltration into Seasonally Frozen Soil
Water frozen in soil can reduce the soil infiltrability, depending on the water content. We hypothesize that air-filled macropores control the infiltration of a seasonally frozen soil under high saturation degrees. Sprinkling experiments with different intensities on a seasonally frozen soil were…
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Artikel Jurnal
Hydraulic-Mechanical Properties of Unsaturated Granite-Weathered Residual Soil in Korea
This study performed a series of experiments to examine the hydraulic-mechanical properties of granite-weathered residual soil in the Korean Peninsula. Particular attention was paid to the soil-water characteristic curve (SWCC) and shear strength under various stress states and matric suction…
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Artikel Jurnal
Impact of Infiltration Rate on Residual Air Distribution and Hydraulic Conductivity
The dynamics of water infiltration into soil have a strong influence on the subsequent distribution of air trapped inside pores. We present results of two infiltration experiments conducted on an artificially prepared sample under ponding and drip irrigation boundary conditions, with concurrent…
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Artikel Jurnal
Predicting the Fate of Preferentially Moving Herbicides
Simulation of preferential flow remains a challenge despite being a recognized phenomenon. With short-interval data, we adapted and tested the preferential flow model (PFM) to simulate the vertical transport of herbicides to lower soil layers. The PFM divides the soil profile into a top…
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Artikel Jurnal
Steady Water Flow with Interacting Point Source–Point Sink–Water Table in a Cylindrical Soil Domain
A previously derived analytical solution to the quasi-linear form of the water flow equation is used to analyze (i) steady, coupled plant water uptake from a surface water emitter in a confined cylindrical soil domain with a non-evaporating surface in the presence of a shallow water table, and (ii)…
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Artikel Jurnal
Experimental and Numerical Studies of Saturation Overshoot during Infiltration into a Dry Soil
Downward infiltration of water into almost dry soil, when there is no ponding at the soil surface, often occurs in the form of fingers, with saturation overshoot at the finger tips. While this is well known, there is still uncertainty about the exact saturation pattern within fingers. We performed…
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Artikel Jurnal
Electrical Resistivity of a Partially Saturated Porous Medium at Subzero Temperatures
Electrical resistivity tomography has been used in many frozen ground applications to delineate frozen and unfrozen areas of the subsurface and monitor changes with time. In these studies, the amount of unfrozen water remaining in the pore space at subzero temperatures is often a parameter of…
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Artikel Jurnal
The Effect of Intraparticle Porosity and Interparticle Voids on the Hydraulic Properties of Soilless Media
An essential component of a building-integrated vegetation system, such as an extensive green roof, is the layer of lightweight planting medium that supports rooting and stores water. Predicting and describing the stormwater management performance of green roofs requires reliable data regarding the…
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Artikel Jurnal
Delineating Site-Specific Management Zones and Evaluating Soil Water Temporal Dynamics in a Farmer’s Field in Kentucky
Due to spatial variability of soil genesis, topography, and resulting soil properties in farmers’ fields, soil and crop processes vary in space and time. Therefore, optimum rates and timing of resource applications, such as nutrients and irrigation water, may vary as well. It remains a challenge to…
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Artikel Jurnal
Leaching of Five Pesticides of Contrasting Mobility through Frozen and Unfrozen Soil
Field and laboratory studies show increased leaching of pesticides through macropores in frozen soil. Fast macropore flow has been shown to reduce the influence of pesticide properties on leaching, but data on these processes are scarce. The objective of this study was to investigate the effect of…