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 Author:
 Chen, J. S.; Mansell, R. S.; NkediKizza, P.; Burgoa, B. A.
 Source:
 Soil Science Society of America journal 1996 v.60 no.1 pp. 4248
 ISSN:
 03615995
 Subject:
 unsaturated flow, etc ; sandy soils; acid soils; phosphorus; sorption; kinetics; soil; soil solution; mathematical models; Show all 9 Subjects
 Abstract:
 ... Sorbentsorbate interactions heavily retard the movement of P during water flow in most soils. The effect of soil/solution ratio on sorption kinetics and movement of P during unsteady unsaturated water flow were investigated. A series of batch experiments with soil/solution ratios ranging from 0.1 to 6.4 Mg m were conducted to obtain sorption rate coefficients. Aqueous P solutions (100–800 g m) we ...
 DOI:
 10.2136/sssaj1996.03615995006000010009x

https://dx.doi.org/10.2136/sssaj1996.03615995006000010009x
 Author:
 Romano, C.G.; Frind, E.O.; Rudolph, D.L.
 Source:
 Ground water 1999 v.37 no.4 pp. 625632
 ISSN:
 0017467X
 Subject:
 unsaturated flow, etc ; seepage; groundwater flow; saturated flow; simulation models; aquifers; mathematical models; unsaturated hydraulic conductivity; groundwater recharge; streams; Show all 10 Subjects
 Abstract:
 ... A fully saturated, freesurface ground water flow model and a variably saturated model are applied to the solution of the freesurface ground water flow problem in order to determine the influence of the unsaturated flow component on the accuracy of the saturated flow solution and the water balance for homogeneous systems. The significance of the seepage face that must exist to provide a transitio ...
 DOI:
 10.1111/j.17456584.1999.tb01151.x

http://dx.doi.org/10.1111/j.17456584.1999.tb01151.x
 Author:
 Abbaspour, Karim C.; Sonnleitner, Marion A.; Schulin, Rainer
 Source:
 Soil Science Society of America journal 1999 v.63 no.3 pp. 501509
 ISSN:
 03615995
 Subject:
 unsaturated flow, etc ; simulation models; algorithms; soil water content; pressure; water flow; lysimeters; statistical analysis; stochastic processes; geostatistics; uncertainty; Show all 11 Subjects
 Abstract:
 ... An increasingly attractive alternative to the direct measurement of soil hydraulic properties is the use of inverse procedures. We investigated the consequences of using different variables or combinations of variables from among pressure head, water content, and cumulative outflow on the estimation of hydraulic parameters by inverse modeling. We also looked at a new multiplicative formulation of ...
 DOI:
 10.2136/sssaj1999.03615995006300030012x

https://dx.doi.org/10.2136/sssaj1999.03615995006300030012x
 Author:
 de Rooij, Gerrit H.; de Vries, Peter
 Source:
 Journal of environmental quality 1999 v.28 no.2 pp. 493497
 ISSN:
 00472425
 Subject:
 unsaturated flow, etc ; Monte Carlo method; cost effectiveness; groundwater; leaching; models; soil heterogeneity; soil hydraulic properties; solutes; topsoil; Show all 10 Subjects
 Abstract:
 ... Soil heterogeneity hampers our ability to calculate fieldscale solute leaching. Many of the existing fieldscale modeling attempts are laborious, time consuming, and computationally demanding. NonRichardstype flows (e.g., fingering) cannot be handled by methods based solely on the heterogeneity of the soil hydraulic properties. We developed a time and costeffective approach that starts with a ...
 DOI:
 10.2134/jeq1999.00472425002800020014x

https://dx.doi.org/10.2134/jeq1999.00472425002800020014x
 Author:
 Scanlon, B.R.; Paine, J.G.; Goldsmith, R.S.
 Source:
 Ground water 1999 v.37 no.2 pp. 296304
 ISSN:
 0017467X
 Subject:
 unsaturated flow, etc ; deserts; semiarid zones; semiarid soils; playa soils; electrical conductivity; soil chemistry; chlorides; clay fraction; soil water content; Texas; Show all 11 Subjects
 Abstract:
 ... The use of apparent electrical conductivity (EC(a) measured with electromagnetic (EM) induction was examined as a reconnaissance tool for characterizing unsaturated flow in a semiarid region in the Chihuahuan Desert of Texas. Aboveground conductivity meters (EM31 and EM38) were used to measure EC(a) along transects in various geomorphic settings. Eight boreholes were drilled at different locations ...
 DOI:
 10.1111/j.17456584.1999.tb00987.x

http://dx.doi.org/10.1111/j.17456584.1999.tb00987.x
 Author:
 Ferre, T.P.A.; Nissen, H.H.; Simunek, J.
 Source:
 Vadose zone journal 2002 v.1 no.2
 ISSN:
 15391663
 Subject:
 unsaturated flow, etc ; soil water content; wetting front; time domain reflectometry; spatial variation; dielectric properties; probes (equipment); sand; mathematical models; mathematics and statistics; Show all 10 Subjects
 Abstract:
 ... Many measurement methods are considered to return point values of volumetric water content, water pressure, or other hydrologically relevant properties. However, many methods have spatially distributed measurement sensitivities, averaging a property of interest over some sample volume. In this investigation, we study the effects of the spatially distributed measurement sensitivity of time domain r ...

 Author:
 Lu, Z.; Zhang, D.
 Source:
 Vadose zone journal 2002 v.1 no.1
 ISSN:
 15391663
 Subject:
 unsaturated flow, etc ; saturated flow; porous media; vadose zone; soil water movement; mathematical models; stochastic processes; equations; Monte Carlo method; temporal variation; spatial variation; Show all 11 Subjects
 Abstract:
 ... In this study, on the basis of the van GenuchtenMualem constitutive relationship, we develop a general nonstationary stochastic model for transient, variably saturated flow in randomly heterogeneous media with the method of moment equations. We first derive partial differential equations governing the statistical moments of the flow quantities by perturbation expansions and then implement these e ...

 Author:
 Weigand, H.; Totsche, K.U.; KogelKnabner, I.; Annweiler, E.; Richnow, H.H.; Michaelis, W.
 Source:
 European journal of soil science 2002 v.53 no.1 pp. 7181
 ISSN:
 13510754
 Subject:
 unsaturated flow, etc ; polycyclic hydrocarbons; soil pollution; polluted soils; biodegradation; mass transfer; soil pH; electrical conductivity; anions; organic compounds; dissolved organic carbon; Show all 11 Subjects
 DOI:
 10.1046/j.13652389.2002.00427.x

http://dx.doi.org/10.1046/j.13652389.2002.00427.x
 Author:
 Yang, Y.J.; Spencer, R.D.; Mersmann, M.A.; Gates, T.M.
 Source:
 Ground water 1995 v.33 no.6 pp. 927935
 ISSN:
 0017467X
 Subject:
 unsaturated flow, etc ; groundwater contamination; aromatic hydrocarbons; benzene; toluene; xylene; groundwater flow; aquifers; equations; biodegradation; Show all 10 Subjects
 Abstract:
 ... Concentration ratios of benzene, toluene, ethylbenzene, and xylenes (BTEX) in ground water can be used for groundwater contaminant plume differentiation and source determination. Computer modeling utilizing BTEX soilwater partitioning coefficients and biodegradation rates shows that hydraulic dispersion, retardation, and biodegradation do not significantly modify the BTEX concentration ratios in ...
 DOI:
 10.1111/j.17456584.1995.tb00038.x

http://dx.doi.org/10.1111/j.17456584.1995.tb00038.x
 Author:
 Moench, A.F.
 Source:
 Ground water 1995 v.33 no.3 pp. 378384
 ISSN:
 0017467X
 Subject:
 unsaturated flow, etc ; groundwater flow; aquifers; wells; equations; mathematical models; saturated flow; water table; Show all 8 Subjects
 Abstract:
 ... A Laplace transform solution is presented for flow to a well in a homogeneous, watertable aquifer with noninstantaneous drainage of water from the zone above the water table. The Boulton convolution integral is combined with Darcy's law and used as an upper boundary condition to replace the condition used by Neuman. Boulton's integral derives from the assumption that water drained from the unsatu ...
 DOI:
 10.1111/j.17456584.1995.tb00293.x

http://dx.doi.org/10.1111/j.17456584.1995.tb00293.x
 Author:
 Baker, D.L.
 Source:
 Ground water 1995 v.33 no.3 pp. 385390
 ISSN:
 0017467X
 Subject:
 unsaturated flow, etc ; sand; sandy soils; equations; unsaturated hydraulic conductivity; soil water content; mathematics and statistics; Show all 7 Subjects
 Abstract:
 ... The true Darcian interblock conductivity mean for vertical unsaturated flow, Kv, is derived from Darcy's law, q/Ks = Kv (dH/dx), and the assumption that flow is constant between grid centers. It can be expressed as Kv = (delta x Kxdelta p Kh)/(delta xdelta p), where Kx is the gravity flow mean, Kh is the capillary flow mean, and H = xp (total head = elevation matric suction). Plotting contours ...
 DOI:
 10.1111/j.17456584.1995.tb00294.x

http://dx.doi.org/10.1111/j.17456584.1995.tb00294.x
 Author:
 Nachabe, M.H.; Islas, A.L.; Illangasekare, T.H.
 Source:
 Ground water 1995 v.33 no.2 pp. 304310
 ISSN:
 0017467X
 Subject:
 unsaturated flow, etc ; soil water movement; equations; pollutants; mathematical models; unsaturated hydraulic conductivity; mathematics and statistics; solutes; Show all 8 Subjects
 Abstract:
 ... Analytical solutions for the water flow and solute transport equations in the unsaturated zone are presented. We use the Broadbridge and White nonlinear model to solve the Richards' equation for vertical flow under a constant infiltration rate. Then we extend the water flow solution and develop an exact parametric solution for the advectiondispersion equation. The method of characteristics is ado ...
 DOI:
 10.1111/j.17456584.1995.tb00285.x

http://dx.doi.org/10.1111/j.17456584.1995.tb00285.x
 Author:
 Woldt, W.E.; Hagemeister, M.E.; Jones, D.D.
 Source:
 Ground water 1998 v.36 no.6 pp. 966974
 ISSN:
 0017467X
 Subject:
 unsaturated flow, etc ; groundwater contamination; geology; kriging; surveys; saturated flow; electrical conductivity; sand; gravel; landfill leachates; landfills; Nebraska; Show all 12 Subjects
 Abstract:
 ... This paper develops a geoelectrical and geostatisticalbased methodology that can be used to screen unregulated landfills for the presence of leachate and obtain an approximation of the vertical/spatial extent of waste. The methodology uses a surface electromagnetic (EM) survey combined with indicator kriging. Indicator kriging allows for the use of EM data that have been collected over highly ele ...
 DOI:
 10.1111/j.17456584.1998.tb02103.x

http://dx.doi.org/10.1111/j.17456584.1998.tb02103.x
 Author:
 Ressler, D.E.; Horton, R.; Kluitenberg, G.J.
 Source:
 Soil science 1998 v.163 no.8 pp. 601610
 ISSN:
 0038075X
 Subject:
 unsaturated flow, etc ; Udolls; aquic regimes; agricultural soils; macropores; soil management; chlorides; application methods; leaching; preferential flow; porosity; solutes; Show all 12 Subjects
 DOI:
 10.1097/0001069419980800000001

http://dx.doi.org/10.1097/0001069419980800000001
 Author:
 Kodesova, R.; Gribb, M.M.; Simunek, J.
 Source:
 Soil science 1998 v.163 no.6 pp. 436453
 ISSN:
 0038075X
 Subject:
 unsaturated flow, etc ; soil analysis; hydraulic conductivity; soil water content; soil water retention; wetting front; pressure; optimization; estimation; simulation models; Show all 10 Subjects
 DOI:
 10.1097/0001069419980600000002

http://dx.doi.org/10.1097/0001069419980600000002
 Author:
 Mace, A.; Rudolph, D.L.; Kachanoski, R.G.
 Source:
 Ground water 1998 v.36 no.3 pp. 465475
 ISSN:
 0017467X
 Subject:
 unsaturated flow, etc ; unsaturated hydraulic conductivity; soil water retention; sand; gravel; soil water content; glacial deposits; saturated flow; mathematical models; Massachusetts; Show all 10 Subjects
 Abstract:
 ... The performance of parametric models used to describe soil water retention (SWR) properties and predict unsaturated hydraulic conductivity (K) as a function of volumetric water content (theta) is examined using SWR and K(theta) data for coarse sand and gravel sediments. Six 70 cm long, 10 cm diameter cores of glacial outwash were instrumental at eight depths with porous cup tensiometers and time d ...
 DOI:
 10.1111/j.17456584.1998.tb02818.x

http://dx.doi.org/10.1111/j.17456584.1998.tb02818.x
 Author:
 Langner, H. W.; Wraith, J. M.; Inskeep, W. P.; Gaber, H. M.; Huwe, B.
 Source:
 Soil Science Society of America journal 1998 v.62 no.1 pp. 110113
 ISSN:
 03615995
 Subject:
 unsaturated flow, etc ; soil analysis; soil water movement; saturated flow; pressure; soil water content; monitoring; soil matric potential; solutes; Show all 9 Subjects
 Abstract:
 ... We developed a system to impose, maintain, and monitor constant matric head () and water content (θ) within large soil cores during saturated or unsaturated flow. Critical elements include: (i) delivery of water and chemicals to the column inlet using a modified disk permeameter; (ii) paired time domain reflectometry (TDR) and transducer tensiometer sensors; and (iii) solenoid valves at the outlet ...
 DOI:
 10.2136/sssaj1998.03615995006200010014x

https://dx.doi.org/10.2136/sssaj1998.03615995006200010014x
 Author:
 Lee, S.; McAvoy, D.C.; Szydlik, J.; Schnoor, J.L.
 Source:
 Ground water 1998 v.36 no.1 pp. 123132
 ISSN:
 0017467X
 Subject:
 unsaturated flow, etc ; laundry products; dicarboxylic acids; mathematical models; biodegradation; septic systems; saturated flow; groundwater flow; equations; phosphates; Ontario; Show all 11 Subjects
 Abstract:
 ... A mathematical model was developed for the purpose of predicting the fate and transport of downthedrain household chemicals in septic systems. The model was tested with field data collected from a typical septic system located near Cambridge, Ontario, Canada. Model simulations were in good agreement with field data for the laundry detergent builders tartrate monosuccinate (TMS) and tartrate diss ...
 DOI:
 10.1111/j.17456584.1998.tb01072.x

http://dx.doi.org/10.1111/j.17456584.1998.tb01072.x
 Author:
 Boateng, Samuel
 Source:
 Hydrogeology journal 2001 v.9 no.6 pp. 543554
 ISSN:
 14312174
 Subject:
 unsaturated flow, etc ; algorithms; clay loam soils; coarsetextured soils; finetextured soils; hydraulic conductivity; models; probability; probability distribution; sand; saturated flow; seepage; water content; Show all 13 Subjects
 Abstract:
 ... A variably saturated flow model is coupled to a firstorder reliability algorithm to simulate unsaturated flow in two soils. The unsaturated soil properties are considered as uncertain variables with means, standard deviations, and marginal probability distributions. Thus, each simulation constitutes an unsaturated probability flow event. Sensitivities of the uncertain variables are estimated for ...
 DOI:
 10.1007/s1004000101646

https://dx.doi.org/10.1007/s1004000101646