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Journal name
Vadose zone journal
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Publication year rev
7994-2006
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2006 v.5 no.3
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- Author:
- Abigail E. Faust; Ty P. A. Ferré; Marcel G. Schaap; Andrew C. Hinnell
- Source:
- Vadose zone journal 2006 v.5 no.3 pp. 850-855
- ISSN:
- 1539-1663
- Subject:
- pedotransfer functions; simulation models; evapotranspiration; soil hydraulic properties; groundwater recharge; soil texture; hydrologic models; Arizona
- Abstract:
- ... We examine in-place recharge as an example of the complex, basin-scale hydrologic processes that are being represented with simplified numerical models. The rate and distribution of recharge depend on local meteorological conditions and hydrogeologic properties. The pattern of recharge is defined predominantly by the distribution of net precipitation (precipitation less evapotranspiration), but di ...
- DOI:
- 10.2136/vzj2005.0109
- https://doi.org/10.2136/vzj2005.0109
- Author:
- Jirka Šimůnek; Changming He; Liping Pang; S. A. Bradford
- Source:
- Vadose zone journal 2006 v.5 no.3 pp. 1035-1047
- ISSN:
- 1539-1663
- Subject:
- saturated hydraulic conductivity; bacterial spores; simulation models; gravel; soil pollution; saturated conditions; groundwater contamination; soil colloids; cadmium; solutes; aquifers; porous media; Bacillus subtilis; soil water movement; hydrologic models
- Abstract:
- ... Strongly sorbing chemicals (e.g., heavy metals, radionuclides, pharmaceuticals, and explosives) in porous media are associated predominantly with the solid phase, which is commonly assumed to be stationary. However, recent field- and laboratory-scale observations have shown that in the presence of mobile colloidal particles (e.g., microbes, humic substances, clays, and metal oxides), colloids can ...
- Handle:
- 10113/30981
- DOI:
- 10.2136/vzj2005.0151
- https://doi.org/10.2136/vzj2005.0151
- Author:
- Arnaud Boivin; Jirka Šimůnek; Michel Schiavon; Martinus Th. van Genuchten
- Source:
- Vadose zone journal 2006 v.5 no.3 pp. 838-849
- ISSN:
- 1539-1663
- Subject:
- saturated hydraulic conductivity; simulation models; agricultural soils; clay soils; soil pollution; silty clay soils; herbicide residues; bentazon; tile drainage; silt loam soils; soil transport processes; sandy loam soils; hydrologic models; France
- Abstract:
- ... The purpose of this study was to assess the transport of the herbicide bentazone [3-(1-methylethyl)-1-2,1,3-benzothiadiazin-4(3)-one 2,2-dioxide] in three contrasting tile-drained cultivated field soils subject to otherwise similar experimental conditions. Observed drain discharge rates and chemical concentrations in the drainage water reflected the different transport processes at the three sites ...
- Handle:
- 10113/30979
- DOI:
- 10.2136/vzj2005.0089
- https://doi.org/10.2136/vzj2005.0089
- Author:
- Martha P. L. Whitaker; Ty P. A. Ferré; Bart Nijssen; Jim Washburne
- Source:
- Vadose zone journal 2006 v.5 no.3 pp. 856-859
- ISSN:
- 1539-1663
- Subject:
- soil sampling; drying; ovens; elementary schools; science education; elementary education; soil water content; measurement
- Abstract:
- ... Measuring gravimetric soil water content is a relatively elementary laboratory procedure; however, the inaccessibility of a laboratory oven makes this activity impractical for K–12 students. The Soil Moisture Campaign (SMC) Project of the Global Learning and Observation to Benefit the Environment (GLOBE) Program was developed to use gravimetric water content measurement as an introduction to earth ...
- DOI:
- 10.2136/vzj2005.0075
- https://doi.org/10.2136/vzj2005.0075
- Author:
- Insa Neuweiler; Hartmut Eichel
- Source:
- Vadose zone journal 2006 v.5 no.3 pp. 963-977
- ISSN:
- 1539-1663
- Subject:
- Richards' equation; vadose zone; unsaturated conditions; soil water movement; mathematical models; hydrologic models; porous media
- Abstract:
- ... Upscaling of the Richards equation is important for large-scale modeling of water flow in the unsaturated zone. We derive an upscaled model for Richards' equation in a layered porous medium. Homogenization theory is applied to derive the upscaled equations for slow flow processes. Two flow regimes are compared. The first flow regime is quantified by small Bond numbers, meaning forces due to pressu ...
- DOI:
- 10.2136/vzj2005.0127
- https://doi.org/10.2136/vzj2005.0127
6. Evaluation of Model Complexity and Input Uncertainty of Field-Scale Water Flow and Salt Transport
- Author:
- G. Schoups; J. W. Hopmans
- Source:
- Vadose zone journal 2006 v.5 no.3 pp. 951-962
- ISSN:
- 1539-1663
- Subject:
- simulation models; prediction; inorganic salts; irrigation; vadose zone; leaching; transpiration; irrigated soils; drainage; soil water movement; hydrologic models; crops
- Abstract:
- ... Prediction of large-scale vadose zone water flow and salt transport is affected by errors due to uncertainties in model structure, that is, complexity of representation of hydrologic processes and model input uncertainties such as parameter values, boundary conditions, and initial conditions. Selection of an appropriate level of model complexity must consider these two sources of uncertainty. We i ...
- DOI:
- 10.2136/vzj2005.0130
- https://doi.org/10.2136/vzj2005.0130
- Author:
- T. H. Skaggs; P. J. Shouse; J. A. Poss
- Source:
- Vadose zone journal 2006 v.5 no.3 pp. 824-837
- ISSN:
- 1539-1663
- Subject:
- water reuse; crop models; irrigation water; forage crops; simulation models; irrigation; Medicago sativa; lysimeters; saline water; Thinopyrum elongatum; drainage; water uptake; roots; drainage water; California
- Abstract:
- ... The recycling of agricultural drainage water for irrigation is increasingly viewed as a desirable management practice in areas with limited options for drainage disposal. Modeling is potentially a cost-effective approach to examining design and management options for drainage reuse systems, but questions exist about the accuracy of simulated root water uptake in dynamic, highly saline conditions s ...
- Handle:
- 10113/30978
- DOI:
- 10.2136/vzj2005.0120
- https://doi.org/10.2136/vzj2005.0120
- Author:
- C. Walker; H. S. Lin; D. D. Fritton
- Source:
- Vadose zone journal 2006 v.5 no.3 pp. 860-866
- ISSN:
- 1539-1663
- Subject:
- infiltrometers; soil matric potential; measurement; sand; agricultural soils; silt loam soils; forest soils; sandy soils; transducers (equipment); loamy sand soils
- Abstract:
- ... The tension infiltrometer has become a standard tool for measuring near-saturated soil hydraulic properties. The objective of this study was to examine the dynamics of the supply tension at the interface between the tension infiltrometer and the measured soil using a pressure transducer under different soil conditions and to raise some cautions needed for proper use of this standard device. Infilt ...
- DOI:
- 10.2136/vzj2005.0096
- https://doi.org/10.2136/vzj2005.0096
- Author:
- Mike Schwank; Timothy R. Green; Christian Mätzler; Hansruedi Benedickter; Hannes Flühler
- Source:
- Vadose zone journal 2006 v.5 no.3 pp. 1048-1064
- ISSN:
- 1539-1663
- Subject:
- capacitance; dielectric properties; capacitance probes; soil water content
- Abstract:
- ... Ring-capacitor sensors are used widely for real-time estimation of volumetric soil water content θ from measured resonant frequency f ᵣ, which is directly affected by the bulk soil permittivity ε. However, the relationship f ᵣ(ε) requires improved quantification. We conducted laboratory experiments to characterize the response of the Sentek EnviroSMART sensor system for a full range of ε values fr ...
- Handle:
- 10113/26858
- DOI:
- 10.2136/vzj2006.0009
- https://doi.org/10.2136/vzj2006.0009
- Author:
- P. Cannavo; F. Lafolie; B. Nicolardot; P. Renault
- Source:
- Vadose zone journal 2006 v.5 no.3 pp. 990-1004
- ISSN:
- 1539-1663
- Subject:
- agricultural soils; seasonal variation; soil respiration; dissolved organic carbon; carbon dioxide; soil solution; nitrate nitrogen; soil air; soil microorganisms; denitrifying bacteria; crop production; Zea mays; simulation models; crop residues; corn; biological activity in soil; denitrification; nitrous oxide; rain; biodegradation; vadose zone; France
- Abstract:
- ... Soil CO₂ and N₂O concentrations were simulated with a model predicting C and N transport in the vadose zone during a 7-mo field experiment, after maize (Zea mays L.) harvesting and incorporation of maize residues into the soil. The gas transport model was based on the dusty gas theory and combined with the PASTIS model. During the experiment, soil atmosphere (CO₂ and N₂O), soil solution (NO₃ ⁻ and ...
- DOI:
- 10.2136/vzj2005.0124
- https://doi.org/10.2136/vzj2005.0124
- Author:
- J. Mertens; R. Stenger; G. F. Barkle
- Source:
- Vadose zone journal 2006 v.5 no.3 pp. 917-933
- ISSN:
- 1539-1663
- Subject:
- simulation models; reflectometry; soil water content; leaching; lysimeters; irrigated soils; vadose zone; hydrologic models
- Abstract:
- ... Due to the exponential increase in computational power and increasing awareness of problems associated with vadose zone parameter estimations based on laboratory and in situ measurements during the last decades, the process of automatic model calibration against laboratory or field data is being increasingly used. This is often referred to as inverse modeling and has as a major limitation the inab ...
- DOI:
- 10.2136/vzj2005.0117
- https://doi.org/10.2136/vzj2005.0117
- Author:
- Edward M. Kwicklis; Andrew V. Wolfsberg; Philip H. Stauffer; Michelle A. Walvoord; Michael J. Sully
- Source:
- Vadose zone journal 2006 v.5 no.3 pp. 934-950
- ISSN:
- 1539-1663
- Subject:
- simulation models; arid zones; alluvium; unsaturated conditions; liquids; oxygen; soil water movement; stable isotopes; deuterium; vadose zone; vapors; hydrologic models; Nevada
- Abstract:
- ... Multiphase, multicomponent numerical models of long-term unsaturated-zone liquid and vapor movement were created for a thick alluvial basin at the Nevada Test Site to predict present-day liquid and vapor fluxes. The numerical models are based on recently developed conceptual models of unsaturated-zone moisture movement in thick alluvium that explain present-day water potential and tracer profiles ...
- DOI:
- 10.2136/vzj2006.0021
- https://doi.org/10.2136/vzj2006.0021
- Author:
- P. F. Germann; D. Hensel
- Source:
- Vadose zone journal 2006 v.5 no.3 pp. 867-876
- ISSN:
- 1539-1663
- Subject:
- mathematical models; sandy soils; clay soils; soil water content; loam soils; silty soils; time domain reflectometry; sprinkler irrigation; infiltration (hydrology); soil structure; wetting front; hydrologic models; Switzerland
- Abstract:
- ... Soil structure can significantly enhance or modify infiltration rates and flow pathways in undisturbed field soils. Relations between features of soil structure and features of infiltration were elucidated from the velocities of wetting fronts. To study flow geometries during wetting, 100 sprinkler infiltration experiments were performed in situ at 25 different sites. Applied sprinkler irrigation ...
- DOI:
- 10.2136/vzj2005.0080
- https://doi.org/10.2136/vzj2005.0080
- Author:
- A. Basile; A. Coppola; R. De Mascellis; L. Randazzo
- Source:
- Vadose zone journal 2006 v.5 no.3 pp. 1005-1016
- ISSN:
- 1539-1663
- Subject:
- unsaturated hydraulic conductivity; sandy loam soils; volcanic soils; clay loam soils; soil water characteristic; soil water retention; mathematics and statistics; Italy
- Abstract:
- ... Hydraulic properties should be determined at the scale of the process modeled. The methods to hydraulically characterize a soil in situ remain extremely difficult to implement, requiring measurements of water content and pressure head with adequate time–depth resolution. We recently proposed a method that reduced the number of field measurements required for complete field hydraulic characterizati ...
- DOI:
- 10.2136/vzj2005.0128
- https://doi.org/10.2136/vzj2005.0128
- Author:
- Lutz Weihermüller; Roy Kasteel; Harry Vereecken
- Source:
- Vadose zone journal 2006 v.5 no.3 pp. 886-893
- ISSN:
- 1539-1663
- Subject:
- simulation models; soil water content; soil heterogeneity; solutes; soil water movement; hydrologic models
- Abstract:
- ... Porous cups are widely used to extract soil solution for monitoring solute transport; however, it is not always clear how soil heterogeneity influences solute breakthrough sampled by suction cups. The objective of this study was to evaluate the influence of soil heterogeneity on the breakthrough of solute extracted by suction cups. We conducted numerical simulations using the HYDRUS-2D code. Local ...
- DOI:
- 10.2136/vzj2005.0105
- https://doi.org/10.2136/vzj2005.0105
- Author:
- Steven R. Evett; Judy A. Tolk; Terry A. Howell
- Source:
- Vadose zone journal 2006 v.5 no.3 pp. 894-907
- ISSN:
- 1539-1663
- Subject:
- neutron probes; meters (equipment); soil temperature; soil water content; time domain reflectometry; electromagnetic induction techniques; soil profiles
- Abstract:
- ... Although the neutron moisture meter (NMM) has served the need for accurate soil water content determinations well, increasing regulatory burdens, including the requirement that the NMM not be left unattended, limit the usefulness of the method. Newer methods, which respond to soil electromagnetic (EM) properties, typically allow data logging and unattended operation, but with uncertain precision, ...
- Handle:
- 10113/2200
- DOI:
- 10.2136/vzj2005.0149
- https://doi.org/10.2136/vzj2005.0149
- Author:
- S. Torkzaban; S. M. Hassanizadeh; J. F. Schijven; H. A. M. de Bruin; A. M. de Roda Husman
- Source:
- Vadose zone journal 2006 v.5 no.3 pp. 877-885
- ISSN:
- 1539-1663
- Subject:
- feces; soil pollution; bacteriophages; soil transport processes; sand; sandy soils; unsaturated flow; saturated flow; soil water content; soil pH; ionic strength; adsorption
- Abstract:
- ... The transport of viruses in unsaturated porous media has been a subject of great interest in recent years because of the enhanced removal of these microorganisms compared with saturated conditions. We studied the transport of bacteriophages MS2 and ϕX174, used as surrogate pathogenic viruses, at various water contents and solution chemistries in terms of pH and ionic strength (IS). The objective w ...
- DOI:
- 10.2136/vzj2005.0086
- https://doi.org/10.2136/vzj2005.0086
- Author:
- T. H. Skaggs; J. A. Poss; P. J. Shouse; C. M. Grieve
- Source:
- Vadose zone journal 2006 v.5 no.3 pp. 815-823
- ISSN:
- 1539-1663
- Subject:
- irrigation; forage crops; Medicago sativa; Thinopyrum elongatum; irrigation water; saline water; water reuse; drainage water; evapotranspiration; lysimeters; dry matter accumulation; crop yield; salt tolerance; leaching; California
- Abstract:
- ... In regions lacking outlets for agricultural drainage disposal, the recycling of drainage waters for irrigation is increasingly seen as a viable management option. Vadose zone modeling could potentially assist in the design of management practices for drainage reuse operations, but data are lacking about the accuracy of simulations of root water uptake under the dynamic, saline field conditions tha ...
- Handle:
- 10113/30976
- DOI:
- 10.2136/vzj2005.0119
- https://doi.org/10.2136/vzj2005.0119
- Author:
- K.-J.S. Kung; E. J. Kladivko; C. S. Helling; T. J. Gish; T. S. Steenhuis; D. B. Jaynes
- Source:
- Vadose zone journal 2006 v.5 no.3 pp. 978-989
- ISSN:
- 1539-1663
- Subject:
- macropores; unsaturated hydraulic conductivity; macropore flow; unsaturated flow; silt loam soils; vadose zone; Indiana
- Abstract:
- ... It is well known that there is a spectrum of pores in a soil profile. The conventional use of a single lumped value of soil hydraulic conductivity to describe a spectrum of hydraulically active pores may have unintentionally impeded the development of field-scale chemical transport theory and perhaps indirectly hindered the development of management protocols for chemical application and waste dis ...
- Handle:
- 10113/30982
- DOI:
- 10.2136/vzj2006.0003
- https://doi.org/10.2136/vzj2006.0003
- Author:
- A. L. Pirani; K. R. Brye; T. C. Daniel; B. E. Haggard; E. E. Gbur; J. D. Mattice
- Source:
- Vadose zone journal 2006 v.5 no.3 pp. 1017-1034
- ISSN:
- 1539-1663
- Subject:
- manganese; heavy metals; selenium; soil amendments; seasonal variation; dissolved organic carbon; application rate; soil pollution; pastures; iron; cadmium; drainage; copper; arsenic; poultry manure; leaching; chromium; grassland soils; zinc; nickel; Udults; Arkansas
- Abstract:
- ... More than 1 billion broiler chickens (Gallus gallus domesticus) are produced annually in Arkansas, with nearly 900 Gg of waste (i.e., litter) generated. Poultry litter is typically land applied as a means of disposal to nearby pastures as an organic fertilizer. Aside from essential plant nutrients, poultry litter also contains heavy metals, yet little is known about the potential of these metals t ...
- DOI:
- 10.2136/vzj2005.0138
- https://doi.org/10.2136/vzj2005.0138