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Artikel Jurnal
Using Water Stable Isotopes in the Unsaturated Zone to Quantify Recharge in Two Contrasted Infiltration Regimes
A reliable estimate of recharge is needed for the sustainable management of groundwater resources. Water stable isotope (δO and δH) profiles in the unsaturated zone are frequently used to quantify groundwater recharge based on the seasonality of water isotopic compositions in precipitation. A very…
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Artikel Jurnal
An Observatory of Groundwater in Crystalline Rock Aquifers Exposed to a Changing Environment: Hyderabad, India
Multiscale and long-term work is needed to tackle the scientific challenges found in areas vulnerable to climate change and anthropic pressure. This is the case in the semiarid and drought-prone regions of southern India where freshwater is scarce and agriculture near fast-growing cities is…
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Artikel Jurnal
Quantifying Soil Water and Root Dynamics Using a Coupled Hydrogeophysical Inversion
Plot- to field-scale root distribution data are relatively rare and difficult to measure with traditional methods. Nevertheless, these data are needed to accurately model root water uptake (RWU) processes within agronomic, hydrologic, and terrestrial biosphere models. New tools are needed to…
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Artikel Jurnal
Water Distribution in an Arid Zone Soil: Numerical Analysis of Data from a Large Weighing Lysimeter
Although desert soils cover approximately one third of the Earth’s land surface, surprisingly little is known about their physical properties and how those properties affect the ecology and hydrology of arid environments. The main goal of this study was to advance our understanding of desert soil…
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Artikel Jurnal
Quantification of Water Content during Freeze–Thaw Cycles: A Nuclear Magnetic Resonance Based Method
In analyzing the phase transition and water migration processes in multiphase porous systems, it is helpful to properly evaluate the unfrozen capillary water content and adsorptive water content, respectively. In this study, an innovative procedure was developed to determine the total, adsorptive…
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Artikel Jurnal
Measuring Soil Water Content with Ground Penetrating Radar: A Decade of Progress
Tremendous progress has been made with respect to ground penetrating radar (GPR) equipment, data acquisition, and processing since the establishment of GPR as a tool for soil water content determination in vadose zone hydrology about 25 yr ago. In this update, we aim to provide a critical overview…
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Artikel Jurnal
Stable Isotope Approaches in Vadose Zone Research
Recent developments in the measurement, modeling, and application of stable isotope tools to provide insights on water flow, transport, biogeochemical, and ecological processes in the vadose zone have motivated a special section in . We give an overview of recent advances and challenges in stable…
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Artikel Jurnal
Dry-Out Periods of Rain Sensors vs. Soil Dry-Out: Water Saving Potential and Recommendations
Rain sensors (RSs) are devices that may help to irrigate residential landscapes more efficiently. When a predetermined amount of rain occurs, an RS interrupts the programmed irrigation cycle. When rainfall stops, RSs allow irrigation after a dry-out period. However, no actual RS dry-out times have…
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Artikel Jurnal
Viscous Flow Approach to Rapid Infiltration and Drainage in a Weighing Lysimeter
Rapid infiltration and drainage in a free-draining weighing lysimeter are assessed with a viscous flow approach that is based on the concept of moving water films. The two parameters and of the film per unit volume of the permeable medium together with the rate and duration of water input suffice…
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Artikel Jurnal
Estimating the Contribution of Groundwater to the Root Zone of Winter Wheat Using Root Density Distribution Functions
For winter wheat ( L.) that grows during the rainless season, the contribution of groundwater to the root zone (CGWR) is an important water source for growth. Accurately estimating the CGWR is important for making decisions on irrigation and discharge for winter wheat fields and preventing water…
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Artikel Jurnal
Estimating Field Capacity from Volumetric Soil Water Content Time Series Using Automated Processing Algorithms
Vadose zone measurements of volumetric soil water content (θ) using soil moisture sensors (SMSs) have become more common due to advances in technology and reduction of costs. Soil moisture sensor data exhibit a characteristic cyclical pattern reflecting water flux dynamics into and out of the…
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Artikel Jurnal
A Simple and Improved Model for Describing Soil Hydraulic Properties from Saturation to Oven Dryness
Soil water retention characteristics and hydraulic conductivity from saturation to oven dryness are needed for simulating soil water movement and solute transport, especially in arid and semiarid regions. The aim of this study was to derive a new soil hydraulic model and compare this model with the…
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Artikel Jurnal
Effects of Water Regimes on Methane Emissions in Peatland and Gley Marsh
The increasing frequency of extreme drought and intense precipitation events with global warming may affect CH emissions from different types of wetlands by regulating drying–wetting cycles. To determine the effects of different water regimes on CH emissions, a mesocosm experiment was conducted…
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Artikel Jurnal
Measuring and Modeling Hydraulic Lift of Lolium multiflorum Using Stable Water Isotopes
This study tested a method to quantify and locate hydraulic lift (HL, defined as the passive upward water flow from wetter to dryer soil zones through the plant root system) by combining an experiment using the stable water isotope HO as a tracer with a soil–plant water flow model. Our methodology…
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Artikel Jurnal
Filtering of Periodic Infiltration in a Layered Vadose Zone: 2. Applications and a Freeware Screening Tool
We have developed a screening tool to visualize and conceptualize the filtering properties of a layered vadose zone. Climate projections indicate that rainfall timing and magnitude may change and impact groundwater resources. This increases the importance of understanding how the vadose zone…
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Artikel Jurnal
The Root Zone: Soil Physics and Beyond
This special section of (VZJ) contains 15 contributions focusing on the physical, biological, and chemical aspects of water and solute transport into and through the soil root zone, including root water and solute uptake. The papers stem from presentations at the 2016 Kirkham Conference, “The Root…
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Artikel Jurnal
Assessing SMAP Soil Moisture Scaling and Retrieval in the Carman (Canada) Study Site
In 2015, NASA launched the Soil Moisture Active Passive (SMAP) satellite. Data from this satellite are being exploited to improve forecasting of extreme weather events and delivery of disaster response. International core validation sites (CVSs) have been contributing in situ soil moisture data to…
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Artikel Jurnal
A Matric Flux Potential Approach to Assess Plant Water Availability in Two Climate Zones in Brazil
Predicting soil water availability to plants is important for agricultural and ecological models. Models that explicitly take into account root water uptake and transpiration reduction describe the ability of soil to supply water to plants based on soil hydraulic properties that depend on soil…
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Artikel Jurnal
Comparative Study of a Long-Established Large Weighing Lysimeter and a State-of-the-Art Mini-lysimeter
Weighing lysimeters are a well-established means of accurately obtaining local-scale estimates of actual evapotranspiration (ET), precipitation, and seepage within soils. At the Rietholzbach research catchment in northeastern Switzerland, two weighing lysimeters are in operation. One is a recently…