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Artikel Jurnal
Identifying the Transport Pathways of Dissolved Organic Carbon in Contrasting Catchments
Dissolved organic C (DOC) plays an important role in the cycling and distribution of energy and nutrients. However, factors controlling the transport of DOC both within and between ecosystems are not clear. The aim of this work was to identify the contributing pathways for transport of DOC to…
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Artikel Jurnal
Pore Size Distribution Patterns in Tropical Soils Obtained by Mercury Intrusion Porosimetry: The Multifractal Approach
Mercury intrusion porosimetry (MIP) is commonly used to determine soil pore size distributions (PSDs) in a wide, but incomplete, range of equivalent pore diameters. Mono‐ and multifractal analyses of soil PSDs are useful for analyzing the soil porous system. The main objective of this work was to…
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Artikel Jurnal
Global Sensitivity Analysis for UNSATCHEM Simulations of Crop Production with Degraded Waters
One strategy for maintaining irrigated agricultural productivity in the face of diminishing resource availability is to make greater use of marginal quality waters and lands. A key to sustaining systems using degraded irrigation waters is salinity management. Advanced simulation models and decision…
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Artikel Jurnal
Effects of Lime and Concrete Waste on Vadose Zone Carbon Cycling
In a series of mesocosm experiments, with barley (Hordeum vulgare L.) grown on podzolic soil material, we have investigated inorganic carbon cycling through the gaseous and liquid phases and how it is affected by different soil amendments. The mesocosm amendments comprised the addition of 0, 9.6…
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Artikel Jurnal
Method of In‐Line Bromide Breakthrough Curve Measurements for Column Leaching Experiments
This study presents a new method for deriving the breakthrough curve (BTC) of Br− tracer by measurements in the laboratory. In this method, the breakthrough is recorded by an ion selective electrode placed in a flow cell into which a peristaltic pump redirects part of the effluent. Special care was…
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Artikel Jurnal
Dissolved Organic Matter: Linking Soils and Aquatic Systems
Dissolved organic matter (DOM) plays a crucial role in many important processes that take place in terrestrial and aquatic systems. These include carbon and nutrient cycling, pedogenesis, and microbial metabolism. Here we highlight the results of studies that demonstrate the role of DOM in linking…
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Artikel Jurnal
Development and Calibration of Dual‐Permeability Flow Models with Discontinuous Fault Networks
A sophisticated dual‐permeability flow model of the T‐tunnel complex, Rainier Mesa, Nevada National Security Site, was developed and calibrated to facilitate predictions of radionuclide transport from underground nuclear tests within a perched zone of saturation downward through a series of…
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Artikel Jurnal
Water and Dissolved Carbon Fluxes in an Eroding Soil Landscape Depending on Terrain Position
Leaching of dissolved C in arable hummocky ground moraine soil landscapes is characterized by a spatial continuum of more or less erosion‐affected Luvisols, Calcaric Regosols at exposed positions, and Colluvic Regosols in depressions. Our objective was to estimate the fluxes of dissolved C in four…
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Artikel Jurnal
Heated Fiber Optic Distributed Temperature Sensing: A Dual‐Probe Heat‐Pulse Approach
Implementation of the dual‐probe heat‐pulse (DPHP) approach for measurement of volumetric heat capacity (C) and water content (θ) with distributed temperature sensing heated fiber optic (FO) systems presents an unprecedented opportunity for environmental monitoring (e.g., simultaneous measurement…
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Artikel Jurnal
Spatial‐Scale Prediction of the SVAT Soil Hydraulic Variables Characterizing Stratified Soils on the Tibetan Plateau from an EnKF Analysis of SAR Soil Moisture
In highly stratified soils as on the Tibetan Plateau, uncertainty associated with a vertical profile of soil and hydraulic properties largely restricts the performance of Soil Vegetation Atmosphere Transfer (SVAT) model. In lieu of commonly used pedotransfer functions (PTFs) or artificial neural…
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Artikel Jurnal
The Role of Dissolved Organic Matter in Adsorbing Heavy Metals in Clay‐Rich Soils
Heavy metals (HMs) are toxic to human life and the environment when present in excessive concentrations. Therefore, determining the interactions of HMs with soils and dissolved organic matter (DOM) is essential to predict their fate. To find out the effect of DOM and soil properties (clay minerals…
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Artikel Jurnal
Field‐Scale Sulfur Hexafluoride Tracer Experiment to Understand Long Distance Gas Transport in the Deep Unsaturated Zone
A natural gradient SF6 tracer experiment provided an unprecedented evaluation of long distance gas transport in the deep unsaturated zone (UZ) under controlled (known) conditions. The field‐scale gas tracer test in the 110‐m‐thick UZ was conducted at the U.S. Geological Survey's Amargosa Desert…
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Artikel Jurnal
Fractionation of Dissolved Organic Matter by (Oxy)Hydroxide‐Coated Sands: Competitive Sorbate Displacement during Reactive Transport
Sorptive retention of dissolved organic matter (DOM) at soil particle surfaces controls C flux through the critical zone. Prior studies have shown that pristine Al‐ and Fe‐(oxy)hydroxide surfaces are especially reactive toward DOM sorptive stabilization. However, the impact of progressive and/or…
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Artikel Jurnal
Rapid and Fully Automated Measurement of Water Vapor Sorption Isotherms: New Opportunities for Vadose Zone Research
Eminent environmental challenges such as remediation of contaminated sites, the establishment and maintenance of nuclear waste repositories, or the design of surface landfill covers all require accurate quantification of the soil water characteristic (SWC) at low water contents. Furthermore…
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Artikel Jurnal
Hydraulic Modeling and in situ Electrical Resistivity Tomography to Analyze Ponded Infiltration into a Water Repellent Sand
Water repellency (WR) might affect the spatial and temporal dynamics of a wetting front during infiltration and redistribution in a way that is difficult to predict with standard approaches. Therefore, the objectives of this study were to simulate the wetting plume geometry with a three‐dimensional…
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Artikel Jurnal
Assessing Vadose Zone Biodegradation by a Multicomponent Gas Transport Model
This study calibrated a gas transport model that uses multicomponent approaches, i.e., the dusty gas model (DGM) and Stefan–Maxwell (SM) equations, to soil gas concentration depth profiles to determine aerobic biodegradation rates of hydrocarbons in unsaturated soils. I found that viscous advection…
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Artikel Jurnal
Sensible Heat Balance and Heat‐Pulse Method Applicability to In Situ Soil‐Water Evaporation
A combined heat‐pulse and sensible heat balance method can be used to determine evaporation using temperature measurements and thermal property estimations. The objective of this study was to investigate the applicability of the combined heat‐pulse and sensible heat balance method by comparing…
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Artikel Jurnal
Noninvasive Estimation of Water Retention Parameters by Observing the Capillary Fringe with Magnetic Resonance Sounding
The magnetic resonance sounding (MRS) method is usually applied for delineation and characterization of aquifer system stratification. Its unique property, distinct from other hydrogeophysical methods, is the direct sensitivity to water content in the subsurface. The inversion of MRS data yields…
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Artikel Jurnal
Ecosystem‐Specific Composition of Dissolved Organic Matter
We investigated the molecular composition of dissolved organic matter (DOM) from various rivers, bogs and soil sites to test for their ecosystems unique molecular patterns. This information is prerequisite for searching of new marker compounds that might help tracing the fate of ecosystem‐derived…