790 results
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Journal Article
Parameterization of Root Water Uptake Models Considering Dynamic Root Distributions and Water Uptake Compensation
The spatiotemporal distribution of root water uptake (RWU) depends on the dynamics of the root distribution and compensatory uptake from wetter regions in the root zone. This work aimed to parameterize three RWU models with different representations of compensation: the Feddes–Jarvis model that…
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Journal Article
Rhizosphere-Scale Quantification of Hydraulic and Mechanical Properties of Soil Impacted by Root and Seed Exudates
Using rhizosphere-scale physical measurements, we tested the hypothesis that plant exudates gel together soil particles and, on drying, enhance soil water repellency. Barley ( L. cv. Optic) and maize ( L. cv. Freya) root exudates were compared with chia ( L.) seed exudate, a commonly used root…
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Journal Article
Combining X-ray Computed Tomography and Visible Near-Infrared Spectroscopy for Prediction of Soil Structural Properties
Soil structure is a key soil property affecting a soil’s flow and transport behavior. X-ray computed tomography (CT) is increasingly used to quantify soil structure. However, the availability, cost, time, and skills required for processing are still limiting the number of soils studied. Visible…
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Journal Article
The WASCAL Hydrometeorological Observatory in the Sudan Savanna of Burkina Faso and Ghana
Watersheds with rich hydrometeorological equipment are still very limited in West Africa but are essential for an improved analysis of environmental changes and their impacts in this region. This study gives an overview of a novel hydrometeorological observatory that was established for two…
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Journal Article
Exploring Scale-Specific Controls on Soil Water Content across a 500-Kilometer Transect Using Multivariate Empirical Mode Decomposition
Soil water content (SWC) varies both spatially and temporally and is highly controlled by various factors operating at different intensities and scales. In this study, we investigated the scale-specific controls of SWC along a 500-km transect using multivariate empirical mode decomposition (MEMD)…
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Journal Article
Impact of Flow Velocity on Transport of Graphene Oxide Nanoparticles in Saturated Porous Media
Saturated column experiments were conducted to systematically examine transport of graphene oxide nanoparticles (GONPs) in sand porous media at different solution ionic strengths (ISs) with different flow velocities. Results show that deposition of GONPs increase with decreasing IS. However, the…
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Journal Article
Quantitative Analysis of Water Infiltration in Soil Cores Using X-Ray
X-ray radiography is a suitable approach to study water dynamics in undisturbed soil. However, beam hardening impairs the deduction of soil moisture changes from X-ray attenuation, especially when studying infiltration of water into cylindrical soil columns. We developed a calibration protocol to…
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Journal Article
Evaluation of Factors Driving Seasonal Nitrate Variations in Surface and Underground Systems of a Karst Catchment
A typical mixed-land-use karst catchment in Guizhou Province, southwestern China, with well-developed conduit networks was studied to understand the spatiotemporal variability of nitrate sources and transformation processes. High nitrate concentrations were detected in the karstic study area, which…
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Journal Article
Effect of Biochar Application on Hydraulic Properties of Sandy Soil under Dry and Wet Conditions
Knowledge of soil hydraulic properties under dry (below permanent wilting point) and wet (from saturation to permanent wilting point) conditions is helpful for evaluating soil physical quality and modeling the movement of the substances (water and nutrients) in biochar-amended soils. To investigate…
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Journal Article
Qinghai Lake Basin Critical Zone Observatory on the Qinghai-Tibet Plateau
The surface–subsurface architecture of the critical zone (CZ) regulates the hydrologic and geochemical processes that drive the CZ function. Due to the complex heterogeneity, highly coupled processes, and the dynamic controlling mechanisms across scales, CZ science faces grand challenges on…
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Journal Article
Why Hydrological Maze: The Hydropedological Trigger? Review of Experiments at Chuzhou Hydrology Laboratory
Hydrology is an old discipline due to its early origination, as well as a young discipline due to its insufficient scientific foundation as a natural science. Thus hydrology has long been haunted by a debate between natural functionalities found in observations vs. model results built on many…
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Journal Article
Soil Water Dynamics in Apple Orchards of Different Ages on the Loess Plateau of China
Knowledge of soil water in apple ( Borkh.) orchards is necessary for formulating robust management strategies and sound planning of apple plantations with limited water resources, such as on the Chinese Loess Plateau. In this work, we assessed the relationship between the age of trees and soil…
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Journal Article
Southern Sierra Critical Zone Observatory and Kings River Experimental Watersheds: A Synthesis of Measurements, New Insights, and Future Directions
Sensor networks within the Southern Sierra Critical Zone Observatory (SSCZO) and Kings River Experimental Watersheds (KREW) document changes in the water cycle spanning the west slope of the southern Sierra Nevada in California. The networks were established to document water dynamics throughout…
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Journal Article
In Situ Bioremediation of a Gasoline-Contaminated Vadose Zone: Implications from Direct Observations
In situ bioremediation of a contaminated vadose zone requires implementing hydraulic and chemical conditions that stimulate the development of indigenous bacteria capable of degrading contaminants in the subsurface. We investigated enhanced biostimulation of a gasoline-contaminated deep vadose zone…
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Journal Article
Quantifying Subsurface Lateral Flow along Sloping Horizon Boundaries in Soil Profiles of a Hummocky Ground Moraine
Subsurface lateral flow in hillslope soils depends on lower permeability or texture-contrasting soil horizons. In the arable hummocky soil landscape, erosion processes caused glacial till appearance closer to the soil surface at upslope positions. The objective of this work was to quantify the…
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Journal Article
Long-Term Variability of Soil Moisture in the Southern Sierra: Measurement and Prediction
Using 6 yr (Water Year [WY] 2009–WY 2014) of hourly in situ measurements from a spatially distributed water-balance cluster, we quantified the long-term accuracy of an algorithm used to predict spatial patterns of depth-integrated soil-water storage within the rain–snow transition zone of the…
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Journal Article
Field and Laboratory Hydraulic Characterization of Landslide-Prone Soils in the Oregon Coast Range and Implications for Hydrologic Simulation
Unsaturated zone flow processes are an important focus of landslide hazard estimation. Differences in soil hydraulic behavior between wetting and drying conditions (i.e., hydraulic hysteresis) may be important in landslide triggering. Hydraulic hysteresis can complicate soil hydraulic parameter…
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Journal Article
The Intensively Managed Landscape Critical Zone Observatory: A Scientific Testbed for Understanding Critical Zone Processes in Agroecosystems
In intensively managed landscapes, interactions between surface (tillage) and subsurface (tile drainage) management with prevailing climate/weather alter landscape characteristics, transport pathways, and transformation rates of surface/subsurface water, soil/sediment, and particulate/dissolved…
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Journal Article
Factors that Influence the Vertical Distribution of Soil Water Content in the Critical Zone on the Loess Plateau, China
In arid and semiarid regions, determining the vertical distribution of the soil water content (SWC) in the Earth’s Critical Zone is important for understanding hydrological processes and for evaluating soil water storage (SWS) levels. However, the vertical distribution of SWC and its storage in…
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Journal Article
The East River, Colorado, Watershed: A Mountainous Community Testbed for Improving Predictive Understanding of Multiscale Hydrological–Biogeochemical Dynamics
Extreme weather, fires, and land use and climate change are significantly reshaping interactions within watersheds throughout the world. Although hydrological–biogeochemical interactions within watersheds can impact many services valued by society, uncertainty associated with predicting…