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Artikel Jurnal
Feasibility assessment on use of proximal geophysical sensors to support precision management
Abstract A study was conducted at three sites in North Dakota to strengthen understanding of the usefulness of different proximal geophysical data types in agricultural contexts of varying pedology. This study hypothesizes that electromagnetic induction (EMI), gamma‐ray sensor (GRS), cosmic‐ray…
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Artikel Jurnal
Examining subsurface response to an extreme precipitation event using HYDRUS‐1D
Abstract North‐central Colorado experienced an extreme precipitation event (EPE) in September 2013, during which the equivalent of 80% of the region's annual average precipitation fell in a few days. Widespread flooding occurred above ground, but the short‐ and long‐term subsurface response remains…
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Artikel Jurnal
Calibration and validation of soil water reflectometers
Abstract In this study, we tested soil water reflectometers represented by the CS65x series soil water reflectometers. The objectives were to (a) quantify the sensing volume of the CS65x sensors, (b) evaluate common univariate and multivariate calibration models, and (c) assess the implications of…
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Artikel Jurnal
Soil water potential: A historical perspective and recent breakthroughs
Abstract Soil water potential is a cornerstone in defining the thermodynamic state of soil water required to quantify phenomena such as water phase change, water movement, heat transfer, electric current, chemical transport, and mechanical stress and deformation in the earth's shallow subsurface…
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Artikel Jurnal
In situ measurement of 3D contact angle in sand based on X‐ray computed tomography
Abstract Soil water repellency is traditionally expressed as contact angle (CA) and measured destructively on exposed surfaces or derived from flow behavior or measured forces. These approaches cannot map local heterogeneities in CA, which typically exist in intact soil. Here, we explore the…
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Artikel Jurnal
Developing a soil column system to measure hydrogeophysical properties of unconsolidated sediment
Abstract Geophysical methods have been increasingly used to characterize the Earth's critical zone (CZ) and monitor hydrological processes occurring within it. For a quantitative interpretation, geophysical studies of CZ materials are necessary, and thus require more sophisticated laboratory…
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Artikel Jurnal
Moisture‐dependent anisotropy calculations using the van Genuchten–Mualem model
Abstract Variable, moisture‐dependent anisotropy in unsaturated media is an effective, large‐scale (macroscopic) flow property that results from media heterogeneities at a smaller scale. This technical note documents the variable moisture‐dependent anisotropy calculations using a script for the…
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Artikel Jurnal
Managed aquifer recharge site assessment with electromagnetic imaging: Identification of recharge flow paths
Abstract Surface spreading recharge, the intentional flooding of the ground surface to replenish a groundwater system, is one approach used to mitigate groundwater overdraft in California's Central Valley (CV). Choosing appropriate sites for surface spreading recharge, in regard to the sites’…
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Artikel Jurnal
Controlled drainage and subirrigation suitability in the United States: A meta‐analysis of crop yield and soil moisture effects
Abstract Controlled drainage and subirrigation (CDSI) is an important water management strategy in many regions, but the conditions under which CDSI is most likely to increase crop yield and soil moisture are not fully understood. A meta‐analysis, consisting of 154 pairwise observations from…
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Artikel Jurnal
Bias of stormwater infiltration measurement methods evaluated using numerical experiments
Abstract Infiltration stormwater control measures (SCMs) have the potential to contribute towards mitigating the effects of urbanization on downstream receiving waters. Infiltration SCMs are most often successful when the in‐situ saturated hydraulic conductivity (Ksat) is well characterized. In…
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Artikel Jurnal
Modification of a 3D printer to create geologically realistic heterogeneous sand packs
Abstract There is a need to develop more accessible approaches to generate geologically realistic microheterogeneous structures in quasi‐two‐dimensional flow cells for use in light transmission experiments. In addition to automating the packing procedure to increase repeatability, such approaches…
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Artikel Jurnal
Monitoring critically saturated conditions for shallow landslide occurrence using electrical resistivity tomography
Abstract Soil wetness is an important property in determining the variable disposition of hillslopes to shallow landslides. Recent studies have demonstrated the potential of in situ soil wetness information for landslide early warning. However, the spatial representativeness of in situ sensors may…
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Artikel Jurnal
Relationships among water and gas transport properties in soils from natural and induced clay gradients
Abstract Clay content in soil potentially has strong influence on soil structure and thereby controls soil physical, hydraulic, and gas transport properties. Only few studies have investigated the effect of clay content on saturated hydraulic conductivity (Ks) and gas transport parameters such…
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Artikel Jurnal
Precipitation is the key determinant of topsoil δ15N values in southern Patagonia's semiarid rangelands
Abstract Nitrogen (N) cycling in rangeland soils could potentially be controlled by water supply, stocking rates, or a range of other variables, such as ecosystem N stocks. To gauge the relative importance and elucidate possible interactions among these factors, we measured many abiotic variables…
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Artikel Jurnal
A device to simulate contaminant transfer and surface and subsurface flow through intact soil monoliths
Abstract Many contaminants of agricultural origin are released into rural environments, particularly at the soil surface. Their fate has been extensively investigated in repacked soils, but only few studies have addressed their transport in structurally preserved natural soils. Much remains unknown…
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Artikel Jurnal
A global 1‐km downscaled SMAP soil moisture product based on thermal inertia theory
Abstract Microwave remote sensing technology has been applied to produce soil moisture (SM) retrievals on a global scale for various studies and applications. However, due to the limitations of current technology, the native spatial resolution of currently available passive microwave SM products is…
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Artikel Jurnal
Methods for downhole soil water sensor calibration—Complications of bulk density and water content variations
Abstract Downhole soil volumetric water content (VWC) sensors are used in access tubes to assess the soil water content at multiple depths. If sensor readings are spaced closely enough vertically and are accurate enough, then accurate soil profile water content storage and change in storage can be…
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Artikel Jurnal
A device to collect passive, flow‐weighted water samples from surface runoff
Abstract Obtaining water quality samples from surface runoff is essential for understanding erosion and pollutant transport processes. Existing water sampling devices are expensive, require installation of extensive infrastructure or power supplies, or have limited ability to collect flow‐weighted…
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Artikel Jurnal
Pedotransfer functions developed for calculating soil saturated hydraulic conductivity in check dams on the Loess Plateau in China
Abstract Soil saturated hydraulic conductivity (Ks) is a key soil hydraulic property that determines the hydrological cycle of check dam–dominated catchment areas. However, Ks data are lacking due to the difficulty of directly measuring this variable in deep soil layers. In this study, 45 soil…