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- Author:
- Goldberg, S.; Criscenti, L.J.; Turner, D.R.; Davis, J.A.; Cantrell, K.J.
- Source:
- Vadose zone journal 2007 v.6 no.3 pp. 407
- ISSN:
- 1539-1663
- Subject:
- soil pollution; vadose zone; aquifers; groundwater contamination; pollutants; adsorption; desorption; metal ions; radionuclides; geochemistry; mathematical models; chemical reactions; soil water movement; groundwater flow; saturated flow; unsaturated flow
- Abstract:
- ... Adsorption-desorption reactions are important processes that affect the transport of contaminants in the environment. Various empirical approaches, such as the distribution coefficient and Freundlich and Langmuir isotherm equations, have been used to represent adsorption. The empirical approaches are not capable of accounting for the effects of variable chemical conditions, such as pH, on adsorpti ...
- Handle:
- 10113/11109
- DOI:
- 10.2136/vzj2006.0085
-
http://dx.doi.org/10.2136/vzj2006.0085
- Author:
- Oostrom, M.; Dane, J. H.; Wietsma, T. W.
- Source:
- Vadose zone journal 2007 v.6 no.3 pp. 610-637
- ISSN:
- 1539-1663
- Subject:
- groundwater contamination; groundwater flow; infiltration (hydrology); solutes; porous media; analytical methods; dense nonaqueous phase liquids; saturated flow
- Abstract:
- ... A review is presented of original multidimensional, intermediate-scale experiments involving nonaqueous phase liquid (NAPL) flow behavior, imaging, and detection and quantification with solute tracers. In a companion paper (Oostrom et al., 2006a), experiments related to aqueous dissolution and enhanced remediation were discussed. The experiments investigating flow behavior include infiltration and ...
- DOI:
- 10.2136/vzj2006.0178
-
https://dx.doi.org/10.2136/vzj2006.0178
- Author:
- Gurdak, Jason J.; Hanson, Randall T.; McMahon, Peter B.; Bruce, Breton W.; McCray, John E.; Thyne, Geoffrey D.; Reedy, Robert C.
- Source:
- Vadose zone journal 2007 v.6 no.3 pp. 533-547
- ISSN:
- 1539-1663
- Subject:
- temporal variation; El Nino; evapotranspiration; vadose zone; chlorides; leaching; infiltration (hydrology); nitrate nitrogen; climatic factors; nitrates; water table; High Plains (United States)
- Abstract:
- ... Responses in the vadose zone and groundwater to interannual, interdecadal, and multidecadal climate variability have important implications for groundwater resource sustainability, yet they are poorly documented and not well understood in most aquifers of the USA. This investigation systematically examines the role of interannual to multidecadal climate variability on groundwater levels, deep infi ...
- DOI:
- 10.2136/vzj2006.0087
-
https://dx.doi.org/10.2136/vzj2006.0087
- Author:
- White, Ian; Falkland, Tony; Metutera, Taboia; Metai, Eita; Overmars, Marc; Perez, Pascal; Dray, Anne
- Source:
- Vadose zone journal 2007 v.6 no.3 pp. 581-590
- ISSN:
- 1539-1663
- Subject:
- islands; groundwater; water table; rain; El Nino; drought; wells; infiltration (hydrology); water quality; aquifers; freshwater; saturated hydraulic conductivity; groundwater contamination; Escherichia coli; atolls; Kiribati
- Abstract:
- ... Population centers in low, small islands have water supply problems that are among the most critical in the world. Limited land areas and extremely large soil hydraulic conductivities severely reduce surface runoff and surface storage, so that thin lenses of fresh groundwater floating over seawater comprise the major source of fresh water for people in many atolls. Atoll groundwater is extremely v ...
- DOI:
- 10.2136/vzj2006.0092
-
https://dx.doi.org/10.2136/vzj2006.0092
- Author:
- Sugita, Fumi; Nakane, Kazuro
- Source:
- Vadose zone journal 2007 v.6 no.3 pp. 548-553
- ISSN:
- 1539-1663
- Subject:
- macropores; groundwater contamination; macropore flow; chlorides; infiltration (hydrology); lysimeters; nitrate nitrogen; leaching; porous media; rain; rain intensity; topsoil; climate change; sand; rainfall simulation; nitrates
- Abstract:
- ... Laboratory experiments were conducted to investigate the effects of water input properties on the movement of nitrate in three different porous media. A series of artificial rainfall amounts from 4.0 to 26 mm were applied every 24 h in 10 min durations over a weighing lysimeter packed with either fine sand, field soil over fine sand, or fine sand with artificial macropores. Movements of nitrate, c ...
- DOI:
- 10.2136/vzj2006.0095
-
https://dx.doi.org/10.2136/vzj2006.0095
- Author:
- Taniguchi, Makoto; Uemura, Takeshi; Jago-on, Karen
- Source:
- Vadose zone journal 2007 v.6 no.3 pp. 591-596
- ISSN:
- 1539-1663
- Subject:
- groundwater; water temperature; wells; aquifers; urban areas; urbanization; global warming; air temperature; Japan; South Korea; Thailand
- Abstract:
- ... Subsurface temperature profiles measured in boreholes can be analyzed to infer depths of thermal disturbance and associated surface warming due to combined global warming and urbanization (heat island effects). Asian cities are extremely vulnerable because of rapid increases in population. Average subsurface temperature profiles in four Asian cities (Tokyo, Osaka, Seoul, and Bangkok) were compared ...
- DOI:
- 10.2136/vzj2006.0094
-
https://dx.doi.org/10.2136/vzj2006.0094
- Author:
- Schroder, T.; Javaux, M.; Vanderborght, J.; Vereecken, H.
- Source:
- Vadose zone journal 2007 v.6 no.3 pp. 524-526
- ISSN:
- 1539-1663
- Subject:
- simulation models; soil water content; equations; transpiration; water uptake; roots; soil water movement
- DOI:
- 10.2136/vzj2007.0036
-
http://dx.doi.org/10.2136/vzj2007.0036
- Author:
- Sheikh, Vahedberdi; van Loon, E. Emiel
- Source:
- Vadose zone journal 2007 v.6 no.3 pp. 638-650
- ISSN:
- 1539-1663
- Subject:
- vadose zone; soil water content; soil water; mathematical models; agricultural watersheds; model validation; unsaturated conditions; hydrologic models; Netherlands
- Abstract:
- ... The utility of an unsaturated zone soil moisture model is not only its ability to describe the soil moisture dynamics at a given point but also the possibility to generalize the results to larger areas. In this study we investigated the predictive performance of a one-dimensional unsaturated zone soil moisture model when applied at point, field, response unit, and catchment scales, using detailed ...
- DOI:
- 10.2136/vzj2006.0077
-
https://dx.doi.org/10.2136/vzj2006.0077
- Author:
- Amidu, Sikiru A.; Dunbar, John A.
- Source:
- Vadose zone journal 2007 v.6 no.3 pp. 511-523
- ISSN:
- 1539-1663
- Subject:
- soil cracks; saturated conditions; Vertisols; soil micromorphology; evaporation; soil water; preferential flow; electrical resistance; Texas
- Abstract:
- ... Vertisols are complex soils with high clay content (>30%), high shrink–swell potential, and microrelief features known as gilgai We applied field and laboratory electrical-resistivity measurements to characterize seasonal wetting and drying of a Texas Vertisol, and to quantify the effects of gilgai and cracks on seasonal hydrodynamics of the soil. Thirty-two multielectrode resistivity-profiling li ...
- DOI:
- 10.2136/vzj2007.0005
-
https://dx.doi.org/10.2136/vzj2007.0005
- Author:
- Deurer, M.; Bachmann, J.
- Source:
- Vadose zone journal 2007 v.6 no.3 pp. 446-457
- ISSN:
- 1539-1663
- Subject:
- simulation models; contact angle; equations; water repellent soils; infiltration (hydrology); seasonal variation; wettability; hydrophobicity; forest soils; soil profiles; soil water retention; drainage; wetting front
- Abstract:
- ... A new approach by Bachmann et al. describes the wetting behavior of soil with reduced wettability with a macroscopic dynamic contact angle concept. The contact angle (CA) is hysteretic and depends on both time and water content. A maximum CA is reached at the permanent wilting point and decreases during rewetting until achieving the minimum CA at a water content close to field capacity. To simulat ...
- DOI:
- 10.2136/vzj2006.0061
-
https://dx.doi.org/10.2136/vzj2006.0061
- Author:
- Bachmann, J.; Deurer, M.; Arye, G.
- Source:
- Vadose zone journal 2007 v.6 no.3 pp. 436-445
- ISSN:
- 1539-1663
- Subject:
- water repellent soils; soil water movement; contact angle; soil water retention; mathematical models; equations; hydrophobicity; wettability
- Abstract:
- ... In the past, hydrophobic soils have been associated mostly with preferential flow phenomena. It has become increasingly evident that besides the phenomena of extremely (hydrophobic) water-repellent soils, soils with reduced wettability are more the rule than the exception. Despite the extensive literature on the hydraulic behavior of water-repellent soil, a conceptual model flexible enough to desc ...
- DOI:
- 10.2136/vzj2006.0060
-
https://dx.doi.org/10.2136/vzj2006.0060
- Author:
- Weeks, Edwin P.; McMahon, Peter B.
- Source:
- Vadose zone journal 2007 v.6 no.3 pp. 496-510
- ISSN:
- 1539-1663
- Subject:
- land use change; grasslands; agricultural soils; rhizosphere; Zea mays; rangeland soils; corn; arable soils; biological activity in soil; gas emissions; denitrification; water table; vadose zone; nitrous oxide; High Plains (United States)
- Abstract:
- ... Concentration profiles of N₂O, a greenhouse gas, and the conservative trace gases SF₆ and the chlorofluorocarbons CFC-11, CFC-12, CFC-113, and were measured periodically through thick vadose zones at nine sites in the U.S. High Plains. The CFC and SF₆ measurements were used to calibrate a one-dimensional gas diffusion model, using the parameter identification program UCODE. The calibrated model wa ...
- DOI:
- 10.2136/vzj2006.0164
-
https://dx.doi.org/10.2136/vzj2006.0164
- Author:
- Fagerlund, F.; Illangasekare, T.H.; Niemi, A.
- Source:
- Vadose zone journal 2007 v.6 no.3 pp. 483-495
- ISSN:
- 1539-1663
- Subject:
- mathematical models; saturated conditions; groundwater contamination; infiltration (hydrology); aquifers; porous media; sand; dense nonaqueous phase liquids; saturated flow
- Abstract:
- ... We performed a series of well-controlled laboratory experiments investigating the infiltration and subsequent immobilization of nonaqueous-phase liquid (NAPL) in saturated heterogeneous media. A system of two distinct aquifer zones separated by a dipping interface was considered. Heterogeneity was represented by a spatially correlated random field with known geostatistical parameters in one zone i ...
- DOI:
- 10.2136/vzj2006.0172
-
https://dx.doi.org/10.2136/vzj2006.0172
- Author:
- Fagerlund, F.; Illangasekare, T.H.; Niemi, A.
- Source:
- Vadose zone journal 2007 v.6 no.3 pp. 471-482
- ISSN:
- 1539-1663
- Subject:
- mathematical models; saturated conditions; groundwater contamination; infiltration (hydrology); porous media; sand; dense nonaqueous phase liquids; saturated flow
- Abstract:
- ... Accurate data to understand the migration and entrapment of nonaqueous-phase liquids (NAPLs) in heterogeneous formations are presently lacking. A series of well-controlled laboratory experiments were conducted to investigate the infiltration and subsequent immobilization of dense NAPLs in saturated heterogeneous media. The focus of this first study was the development of a special experimental met ...
- DOI:
- 10.2136/vzj2006.0171
-
https://dx.doi.org/10.2136/vzj2006.0171
- Author:
- Green, T.R.; Bates, B.C.; Charles, S.P.; Fleming, P.M.
- Source:
- Vadose zone journal 2007 v.6 no.3 pp. 597
- ISSN:
- 1539-1663
- Subject:
- elevated atmospheric gases; carbon dioxide; climate change; groundwater recharge; physical models; simulation models; General Circulation Models; aquifers; infiltration (hydrology); saturated flow; evapotranspiration; vegetation; plant growth; senescence; subtropics; Mediterranean climate; Western Australia; Queensland
- Abstract:
- ... Increasing concentrations of atmospheric CO2 will alter regional rainfall and evapotranspiration regimes that drive groundwater recharge. Improved methods of simulation and analysis are needed for assessing the potential sensitivities of soil-water-vegetation systems to climate change. This study demonstrates methods for generating climates and simulating soil-water and vegetation dynamics in resp ...
- Handle:
- 10113/11017
- DOI:
- 10.2136/vzj2006.0099
-
http://dx.doi.org/10.2136/vzj2006.0099
- Author:
- Altfelder, Sven; Duijnisveld, Wilhelmus H. M.; Streck, Thilo; Meyenburg, Gunnar; Utermann, Jens
- Source:
- Vadose zone journal 2007 v.6 no.3 pp. 668-678
- ISSN:
- 1539-1663
- Subject:
- trace elements; heavy metals; leaching; cadmium; equations; simulation models; Monte Carlo method; risk assessment; groundwater contamination; soil pH; soil organic carbon; clay fraction; spatial variation; sorption; Germany
- Abstract:
- ... The application of leaching models to predict field-scale heavy metal transport has been successful at several sites. Past studies involved site-specific sorption experiments to quantify the leaching process and to investigate its spatial variability. Uncertainty due to lack of knowledge was frequently ignored. Here we present a leaching model that is based on an extended Freundlich equation to de ...
- DOI:
- 10.2136/vzj2006.0148
-
https://dx.doi.org/10.2136/vzj2006.0148
- Author:
- van Roosmalen, Lieke; Christensen, Britt S. B.; Sonnenborg, Torben O.
- Source:
- Vadose zone journal 2007 v.6 no.3 pp. 554-571
- ISSN:
- 1539-1663
- Subject:
- overland flow; stream flow; climate models; winter; geographical variation; streams; climate change; aquifers; watershed hydrology; summer; groundwater; hydrologic models; Denmark
- Abstract:
- ... Regional impact studies of the effects of future climate change are necessary because projected changes in meteorological variables vary regionally, and different hydrological systems can react in various ways to the same changes. In this study the effects of climate change on groundwater recharge, storage, and discharge to streams are compared in two geologically and climatologically different re ...
- DOI:
- 10.2136/vzj2006.0093
-
https://dx.doi.org/10.2136/vzj2006.0093
- Author:
- Aerts, Jeroen; Lasage, Ralph; Beets, Wisse; de Moel, Hans; Mutiso, Gideon; Mutiso, Sam; de Vries, Arjen
- Source:
- Vadose zone journal 2007 v.6 no.3 pp. 572-580
- ISSN:
- 1539-1663
- Subject:
- water harvesting; climate change; aquifers; dams (hydrology); rain; runoff; Kenya
- Abstract:
- ... This study shows the robustness of subsurface storage using sand dams under long-term climate change for the Kitui District in Kenya. Climate change is predicted to enhance potential evaporation through an increase in average temperature of about 3°C. Even though average precipitation will also increase, approximately 13%, the net water availability is projected to decrease in the future, about 1 ...
- DOI:
- 10.2136/vzj2006.0097
-
https://dx.doi.org/10.2136/vzj2006.0097
- Author:
- Liu, H. H.; Zhang, Y. Q.; Molz, F. J.
- Source:
- Vadose zone journal 2007 v.6 no.3 pp. 679-683
- ISSN:
- 1539-1663
- Subject:
- rocks; equations; groundwater flow; solutes; aquifers; diffusion
- Abstract:
- ... Matrix diffusion is an important process affecting solute transport in fractured rock, and the matrix diffusion coefficient is a key parameter for describing this process. Previous studies have indicated that effective matrix diffusion coefficient values obtained from a number of field tracer tests are enhanced in comparison with local values and may increase with test scale. In this communication ...
- DOI:
- 10.2136/vzj2006.0140
-
https://dx.doi.org/10.2136/vzj2006.0140