SAES-422 Multistate Research Activity Accomplishments Report
Sections
Status: Approved
Basic Information
- Project No. and Title: W188 : Characterization of Flow and Transport Processes in Soils at Different Scales
- Period Covered: 01/01/2001 to 12/01/2001
- Date of Report: 04/12/2002
- Annual Meeting Dates: 01/03/2002 to 01/04/2002
Participants
Arizona A.W. Warrick, Department of Soil, Water and Environmental Science, University of Arizona, Tucson, AZ 85721 P.J. Wierenga, Department of Soil, Water and Environmental Science, University of Arizona, Tucson, AZ 85721 W. Rasmussen, Department of Soil, Water and Environmental Science, University of Arizona, Tucson, AZ 85721 P. Ferre, Department of Hydrology and Water Resources, University of Arizona, Tucson, AZ 85721 California M. Ghodrati, Dept. of Env. Sci. Pol. Mgmt., University of California, Berkeley, CA 94720-3110 J.W. Hopmans, Dept. of LAWR, Hydrologic Science, University of California Davis, CA 95616 W.A. Jury, Dept. of Envir. Sciences, University of California, Riverside, CA 92521 F. Leij, George E. Brown, Jr. Salinity Lab - USDA-ARS, Riverside, CA 92507 D.R. Nielsen, Dept. of LAWR, Hydrologic Science, University of California Davis, CA 95616 D.E. Rolston, Dept. of LAWR, Soil and BioGeochemistry, University of California Davis, CA 95616 P.J. Shouse, George E. Brown, Jr. Salinity Lab - USDA-ARS, Riverside, CA 92507 J. imynek, George E. Brown, Jr. Salinity Lab - USDA-ARS, Riverside, CA 92507 T. Skaggs, George E. Brown, Jr. Salinity Lab - USDA-ARS, Riverside, CA 92507 M.Th. van Genuchten, George E. Brown, Jr. Salinity Lab - USDA-ARS, Riverside, CA 92507 L.Wu, Dept. of Envir. Sciences, University of California, Riverside, CA 92521 Colorado L.R. Ahuja, USDA-ARS, Great Plains System Research Unit Fort Collins, CO 80522 T. Green, USDA-ARS, Great Plains System Research Unit Fort Collins, CO 80522 G. Butters, Dept. of Agronomy, Colorado State University, Ft Collins, CO 80523 Delaware Y. Jin, Dept. of Plant and Soil Sciences, Univ. of Delaware, Newark, DE 10717-1303 Idaho J.B. Sisson, Idaho National Engin. Lab., Idaho Falls, ID 83415-2107 J. Hubbel, Idaho National Engin. Lab., Idaho Falls, ID 83415-2107 Markus Tuller, Dept. of Plant, Soils & Ent. Sci. Univ. of Idaho, Moscow, ID 83844 Illinois T.R. Ellsworth, University of Illinois, Urbana, IL 61801 Indiana J. Cushman, Mathematics Dept., Purdue University, W. Lafayette, IN 47905 P.S.C. Rao, School of Civil Engineering, Purdue University, W. Lafayette, IN 47905 Iowa R. Horton, Dept. of Agronomy, Iowa State University, Ames, IA 50011 D. Jaynes, National Soil Tilth Lab, USDA-ARS, Ames, IA 50011 Kansas G. Kluitenberg, Dept. of Agronomy, Kansas State University, Manhattan, KS 66506 Montana J. M. Wraith, Land Resources and Environ. Sciences, Montana State University, Bozeman, MT 59717-3120 Nevada S.W. Tyler, Hydrologic Sciences Graduate Program, University of Nevada, Reno, NV 89532 M.H. Young, Desert Research Institute, University of Nevada, Las Vegas, NV 89119 New Mexico J.H.M. Hendrickx, New Mexico Tech, Dept. of Geoscience, Socorro, NM 87801 North Dakota F. Casey, Dept. of Soil Science, North Dakota State University, Fargo, ND 58105-5638 Tennessee E. Perfect, Dept. of Geo. Sciences, Univ. Tennessee Knoxville, TN 37996-1410 Utah D. Or, Dept. of Plants, Soils & Biomet., Utah State University, Logan, UT 84322 Washington M. Flury, Dept. of Crop & Soil Sciences, Washington State University, Pullman, WA 99164 J. Wu, Dept. of Biological System Engineering, Washington State University, Pullman, WA 99164 Wyoming R. Zhang, Dept. of Renewable Resources, University of Wyoming, Laramie, WY 82071 CSREES R. Knighton, USAD-CSREES, Washington, DC 20250-2200 Adm. Adv. G.A. Mitchell, Palmer Research Center, 533 E.Fireweed, Palmer,AK 99645
The minutes of the annual meeting and a complete
copy of the annual report may be found on the W-188 website.
copy of the annual report may be found on the W-188 website.
[Minutes]
Accomplishments
Objective 1: To study relationships between flow and transport properties or processes
and the spatial and temporal scales at which these are observed.
The CA-Riverside field investigation of preferential flow patterns during moisture redistribution matured in 2001 and using a combination of soil sampling and dye trace photography found confirmation of their hypothesis that unstable flow begins at the draining front only after the initiation of redistribution which is characterized by a series of flow fingers. University of Minnesota in collaboration with Cornell University, Kazan University (Russia), and Wageningen University (Netherlands) used an
extended Richards equation (REE) applied to linear stability analysis for three flow models in unsaturated porous media. The wetting front for the REE model is conditionally stable (stable for high frequency perturbations and unstable otherwise). Results of this work leads to existence of a wave-number for maximum amplification which relates to the dimensions of fingers in unstable flow alluded to in the Riverside work. Other research at UC-R involved fate of pesticides on golf greens and other turfgrass ecosystems. An important outcome included findings that the fraction of trichlorfon nor chlorpyrifos insecticides lost to leaching, volatilization and clipping was insignificant (< .06% of applied). Outcomes of other research contributing to Objective 1 included:
7 USDA-USSL studied transport of volatile organic chemicals and developed analytical solutions that describe gas movement in layered soil profiles and predict gas flux and concentration. USSL researchers studied the critical area of pathogen transport. They found that pathogen transport was highly dependent on parasite size and soil pore characteristics.
7 USDA-USSL studies have found multidimensional transient water flow models are limited in their applicability because root water uptake is generally treated as one-dimensional. In 2001, researchers developed a very flexible two-dimensional root water uptake model that allows spatial variations of water uptake as influenced by both non-uniform (i.e. drip irrigation) and uniform water application patterns. Collaborative research between USDA-USSL, University of Nevada Reno, and the Desert Research Institute addressed the development of fully coupled flow and geochemical numerical solvers to predict infiltration in mine-altered lands in Nevada. Target contaminants include arsenic, cyanide, and sulfates. The results are reducing contamination and developing cost-effective closure designs for operating mines.
7 UC-Davis studied flow or transport processes across a range of spatial and temporal scales. They concluded that new instrumentation was needed to overcome inherent problems of uncertainties when changing between scales and the nonlinear nature of flow and transport processes in vadose zone hydrology.
7 Iowa State University in collaboration with the Lawrence Berkeley National Lab studied effects of low connectivity on imbibition and solute transport in rock matrices. As predicted by percolation theory, they found that imbibition in sparsely connected porespaces is proportional to time0.26 as compared to time0.5 for cumulative mass imbibition.
7 Iowa State University improved accuracy of water flow and solute transport predictions by developing a simple flow method to estimate hydraulic properties. North Dakota State University is pursuing collaborative research involving MT, MN, and SD on precision agriculture to develop nutrient management zones. This work is funded by a grant from the REEUSDA Initiative for Future Agriculture and Food Sources.
7 Washington State University and the University of Delaware completed a comprehensive review article on fate and transport of viruses in the environment.
OBJECTIVE 2: To develop and evaluate instrumentation and methods of analysis for characterization of flow and transport at different scales
University of Arizona investigated water redistribution of subsurface water using borehole ground penetrating radar (BGPR). They concluded this to be a promising new method for water content profiling that rivals neutron probe for depth and spatial resolution. Other significant accomplishments under this objective included:
7 USDA-USSL developed a rapid and sensitive method to measure the permeability of new low-permeability films for used during soil fumigation. Combination of methodology and improved agricultural film covers will reduce fumigant emissions and increase efficacy of the pesticide.
7 Tension infiltrometers are widely and successfully used to measure hydraulic properties in soil, but not in fractured rock media. USSL has developed a new instrument that appears to meet the requirement for fractured rock.
7 USDA-USSL scientists studied the rate-dependence of unsaturated hydraulic characteristics using steady state and transient flow analysis. They found that water entrapment and pore blockage play a significant role in hydraulic conductivity at high flow rates. They also evaluated the computer program "Rosetta" that uses a number of pedotransfer functions for quicker and cheaper estimates of water retention and hydraulic conductivity. It is available for use by researchers and consultants at http://www.ussl.ars.usda.gov/MODELS/MODELS.HTM
7 USSL research described non-equilibrium flow in soils that has implications for the accelerated movement of fertilizers, pesticides, non-aqueous liquids, and other pollutants. Their approach using laboratory soil cores fitted with tensiometers, combined a numerical solution of governing flow equation (using a modification of HYDRUS-1D) with a Marquardt-Levenberg optimization. Their analysis of flow response demonstrated significant non-equilibrium flow.
7 Colorado State University developed a new continuous flow method that allows estimation of wetting/draining hydraulic conductivity and moisture retention functions over the entire range of plant available soil water. They determined the continuous flow method is ideally suited for evaluating fundamental problems is soil water flow such as temporal variation and spatial scaling of soil hydraulic properties. University of Idaho and Utah State University collaborated on analytical solutions for prediction of sample scale unsaturated hydraulic conductivity derived from pore-scale processes in matrix and structural pore domains.
7 Iowa State University developed a method to measure subsurface water fluxes using a heat pulse sensor and a simpler mathematical relationship that replaces the cumbersome mathematical analysis previously required.
7 Kansas State University determined that the dual-probe heat-pulse (DPHP) method could be used to measure near surface volumetric water content and that forced convection did not limit the function depending on DPHP configuration in the soil.
7 Montana State University and Utah State University improved in situ measurements of soil hydraulic properties that increase accuracy and efficiency in soil and water management. North Dakota State University improved the design of the automated tension infiltrometers by installing a single differential transducer. Measurement precision was increased by two orders of magnitude. NDSU also developed a new method of describing soil water retention curves using a flexible smooth function.
7 Washington State University and Decagon utilized freezing experiments in a new method to determine moisture characteristics in porous media. Network analyzer measurements were made to determine the dielectric properties of frozen porous media as a function of frequency and temperature. WSU also tested the use of dyes in the vadose zone to visualize flow pathways in soils.
7 USDA-CPRL (Bushland, TX) is estimating hydraulic properties in soils using a disc infiltrometer and in situ measurements of infiltration. They found inverse optimization of parameter offers an economical means to infer soil hydraulic properties from in situ measurements. USDA-CPRL also found that soil layering affected this method of estimating hydraulic conductivity. USDA-CPRL has an ongoing comparison of soil moisture sensors at Bushland. In particular, they are evaluating alternatives to the neutron probe by testing the Sentek EnviroSCAN, Sentek Diviner 2000, Trime T3 tube probe, Delta-T Profiler, and a sheathed TDR probe with the neutron probe. It appears that site-specific calibration will be required for many of these and accuracy still may not approach the neutron probe.
OBJECTIVE 3: To apply scale-appropriate methodologies for the management of soil and water resources.
UC-Riverside conducted studies of total maximum daily loads (TMDLs) in agricultural and nursery operations in cooperation with private sector growers to focus on control of sediment movement from the fields during overhead irrigation. In another agricultural project, UC-Riverside found that application of polymers to improve soil physical conditions reduces soil erosion but also can influence adsorption of pesticides and their eventual movement through soil profiles. UC-Davis developed a two- and three-dimensional root uptake model and incorporated it into their flow model. The simulated and measured water content values resulted in R2 values of 0.94 to 0.99, the model is extremely flexible, and allows spatial variation of water uptake as influenced by uniform and non-uniform water application.
USDA-ARS Colorado studied several management practices on soil-plant processes including furrow irrigation and N banding on plant growth and N leaching, evaporation and rain infiltration, reconsolidation on soil water storage, and wheel compaction on permeability, porosity, and water retention. Other research included:
7 ARS-CO scientists have incorporated their research findings into the Root Zone Water Quality Model (RZWQM) which is now available for application.
7 Iowa State and USDA Tilth Lab have collaborated on a number of studies related to crop yield and N management. Multiple discriminate analysis of corn yield in a 32 ha field using cluster analysis allowed deciphering of spatiotemporal patterns into four yield clusters. A second project found tillage-induced barriers or localized compaction and dome (LCD) show potential for reducing N use and nitrate leaching in the Corn Belt.
7 Montana State University in collaboration with CSIRO Land and Water (Australia), evaluated the efficacy of deep drains in lowering shallow saline water tables to maintain suitable rooting zone conditions for wheat. This research will have significant implications for Montana crop-fallow rotations.
MSU also studied soil water implication for invasive weed species and their capacity for utilizing deeper sources of moisture than native plant species.
7 North Dakota State University is using a novel approach for predicting field scale solute transport. A mechanistic-stochastic model was used to predict field-scale solute concentrations by integrating all possible velocities in individual stream tubes. They verified the model using fluorinated benzoic acid tracers under field conditions.
7 USDA-ARS and NDSU investigated transport of bioactive chemicals (i.e. antibiotics, hormones, etc.). They concluded hormones testosterone and estradiol were strongly adsorbed by soils and were transported by a colloidal mechanism, while sulfa-based antibiotics were very mobile indicating ion repulsion.
and the spatial and temporal scales at which these are observed.
The CA-Riverside field investigation of preferential flow patterns during moisture redistribution matured in 2001 and using a combination of soil sampling and dye trace photography found confirmation of their hypothesis that unstable flow begins at the draining front only after the initiation of redistribution which is characterized by a series of flow fingers. University of Minnesota in collaboration with Cornell University, Kazan University (Russia), and Wageningen University (Netherlands) used an
extended Richards equation (REE) applied to linear stability analysis for three flow models in unsaturated porous media. The wetting front for the REE model is conditionally stable (stable for high frequency perturbations and unstable otherwise). Results of this work leads to existence of a wave-number for maximum amplification which relates to the dimensions of fingers in unstable flow alluded to in the Riverside work. Other research at UC-R involved fate of pesticides on golf greens and other turfgrass ecosystems. An important outcome included findings that the fraction of trichlorfon nor chlorpyrifos insecticides lost to leaching, volatilization and clipping was insignificant (< .06% of applied). Outcomes of other research contributing to Objective 1 included:
7 USDA-USSL studied transport of volatile organic chemicals and developed analytical solutions that describe gas movement in layered soil profiles and predict gas flux and concentration. USSL researchers studied the critical area of pathogen transport. They found that pathogen transport was highly dependent on parasite size and soil pore characteristics.
7 USDA-USSL studies have found multidimensional transient water flow models are limited in their applicability because root water uptake is generally treated as one-dimensional. In 2001, researchers developed a very flexible two-dimensional root water uptake model that allows spatial variations of water uptake as influenced by both non-uniform (i.e. drip irrigation) and uniform water application patterns. Collaborative research between USDA-USSL, University of Nevada Reno, and the Desert Research Institute addressed the development of fully coupled flow and geochemical numerical solvers to predict infiltration in mine-altered lands in Nevada. Target contaminants include arsenic, cyanide, and sulfates. The results are reducing contamination and developing cost-effective closure designs for operating mines.
7 UC-Davis studied flow or transport processes across a range of spatial and temporal scales. They concluded that new instrumentation was needed to overcome inherent problems of uncertainties when changing between scales and the nonlinear nature of flow and transport processes in vadose zone hydrology.
7 Iowa State University in collaboration with the Lawrence Berkeley National Lab studied effects of low connectivity on imbibition and solute transport in rock matrices. As predicted by percolation theory, they found that imbibition in sparsely connected porespaces is proportional to time0.26 as compared to time0.5 for cumulative mass imbibition.
7 Iowa State University improved accuracy of water flow and solute transport predictions by developing a simple flow method to estimate hydraulic properties. North Dakota State University is pursuing collaborative research involving MT, MN, and SD on precision agriculture to develop nutrient management zones. This work is funded by a grant from the REEUSDA Initiative for Future Agriculture and Food Sources.
7 Washington State University and the University of Delaware completed a comprehensive review article on fate and transport of viruses in the environment.
OBJECTIVE 2: To develop and evaluate instrumentation and methods of analysis for characterization of flow and transport at different scales
University of Arizona investigated water redistribution of subsurface water using borehole ground penetrating radar (BGPR). They concluded this to be a promising new method for water content profiling that rivals neutron probe for depth and spatial resolution. Other significant accomplishments under this objective included:
7 USDA-USSL developed a rapid and sensitive method to measure the permeability of new low-permeability films for used during soil fumigation. Combination of methodology and improved agricultural film covers will reduce fumigant emissions and increase efficacy of the pesticide.
7 Tension infiltrometers are widely and successfully used to measure hydraulic properties in soil, but not in fractured rock media. USSL has developed a new instrument that appears to meet the requirement for fractured rock.
7 USDA-USSL scientists studied the rate-dependence of unsaturated hydraulic characteristics using steady state and transient flow analysis. They found that water entrapment and pore blockage play a significant role in hydraulic conductivity at high flow rates. They also evaluated the computer program "Rosetta" that uses a number of pedotransfer functions for quicker and cheaper estimates of water retention and hydraulic conductivity. It is available for use by researchers and consultants at http://www.ussl.ars.usda.gov/MODELS/MODELS.HTM
7 USSL research described non-equilibrium flow in soils that has implications for the accelerated movement of fertilizers, pesticides, non-aqueous liquids, and other pollutants. Their approach using laboratory soil cores fitted with tensiometers, combined a numerical solution of governing flow equation (using a modification of HYDRUS-1D) with a Marquardt-Levenberg optimization. Their analysis of flow response demonstrated significant non-equilibrium flow.
7 Colorado State University developed a new continuous flow method that allows estimation of wetting/draining hydraulic conductivity and moisture retention functions over the entire range of plant available soil water. They determined the continuous flow method is ideally suited for evaluating fundamental problems is soil water flow such as temporal variation and spatial scaling of soil hydraulic properties. University of Idaho and Utah State University collaborated on analytical solutions for prediction of sample scale unsaturated hydraulic conductivity derived from pore-scale processes in matrix and structural pore domains.
7 Iowa State University developed a method to measure subsurface water fluxes using a heat pulse sensor and a simpler mathematical relationship that replaces the cumbersome mathematical analysis previously required.
7 Kansas State University determined that the dual-probe heat-pulse (DPHP) method could be used to measure near surface volumetric water content and that forced convection did not limit the function depending on DPHP configuration in the soil.
7 Montana State University and Utah State University improved in situ measurements of soil hydraulic properties that increase accuracy and efficiency in soil and water management. North Dakota State University improved the design of the automated tension infiltrometers by installing a single differential transducer. Measurement precision was increased by two orders of magnitude. NDSU also developed a new method of describing soil water retention curves using a flexible smooth function.
7 Washington State University and Decagon utilized freezing experiments in a new method to determine moisture characteristics in porous media. Network analyzer measurements were made to determine the dielectric properties of frozen porous media as a function of frequency and temperature. WSU also tested the use of dyes in the vadose zone to visualize flow pathways in soils.
7 USDA-CPRL (Bushland, TX) is estimating hydraulic properties in soils using a disc infiltrometer and in situ measurements of infiltration. They found inverse optimization of parameter offers an economical means to infer soil hydraulic properties from in situ measurements. USDA-CPRL also found that soil layering affected this method of estimating hydraulic conductivity. USDA-CPRL has an ongoing comparison of soil moisture sensors at Bushland. In particular, they are evaluating alternatives to the neutron probe by testing the Sentek EnviroSCAN, Sentek Diviner 2000, Trime T3 tube probe, Delta-T Profiler, and a sheathed TDR probe with the neutron probe. It appears that site-specific calibration will be required for many of these and accuracy still may not approach the neutron probe.
OBJECTIVE 3: To apply scale-appropriate methodologies for the management of soil and water resources.
UC-Riverside conducted studies of total maximum daily loads (TMDLs) in agricultural and nursery operations in cooperation with private sector growers to focus on control of sediment movement from the fields during overhead irrigation. In another agricultural project, UC-Riverside found that application of polymers to improve soil physical conditions reduces soil erosion but also can influence adsorption of pesticides and their eventual movement through soil profiles. UC-Davis developed a two- and three-dimensional root uptake model and incorporated it into their flow model. The simulated and measured water content values resulted in R2 values of 0.94 to 0.99, the model is extremely flexible, and allows spatial variation of water uptake as influenced by uniform and non-uniform water application.
USDA-ARS Colorado studied several management practices on soil-plant processes including furrow irrigation and N banding on plant growth and N leaching, evaporation and rain infiltration, reconsolidation on soil water storage, and wheel compaction on permeability, porosity, and water retention. Other research included:
7 ARS-CO scientists have incorporated their research findings into the Root Zone Water Quality Model (RZWQM) which is now available for application.
7 Iowa State and USDA Tilth Lab have collaborated on a number of studies related to crop yield and N management. Multiple discriminate analysis of corn yield in a 32 ha field using cluster analysis allowed deciphering of spatiotemporal patterns into four yield clusters. A second project found tillage-induced barriers or localized compaction and dome (LCD) show potential for reducing N use and nitrate leaching in the Corn Belt.
7 Montana State University in collaboration with CSIRO Land and Water (Australia), evaluated the efficacy of deep drains in lowering shallow saline water tables to maintain suitable rooting zone conditions for wheat. This research will have significant implications for Montana crop-fallow rotations.
MSU also studied soil water implication for invasive weed species and their capacity for utilizing deeper sources of moisture than native plant species.
7 North Dakota State University is using a novel approach for predicting field scale solute transport. A mechanistic-stochastic model was used to predict field-scale solute concentrations by integrating all possible velocities in individual stream tubes. They verified the model using fluorinated benzoic acid tracers under field conditions.
7 USDA-ARS and NDSU investigated transport of bioactive chemicals (i.e. antibiotics, hormones, etc.). They concluded hormones testosterone and estradiol were strongly adsorbed by soils and were transported by a colloidal mechanism, while sulfa-based antibiotics were very mobile indicating ion repulsion.
Impacts
- A major problem that recurs in soils, soil water, and ground water is describing flow and transport of solutes in a complex media with very large spatial and temporal variability. Researchers participating in W-188 have shown that developing an understanding of and management strategies for the unsaturated soil zone near the surface offers the best opportunity to prevent or at least limit pollution of groundwater by chemical and biological agents from agricultural and industrial sources.
- Surface runoff problems from commercial nurseries was partially solved using vegetation filter strips as a demonstration of Management Practices that minimize off-site movement of nutrients and other contaminants.
- The Root Zone Water Quality Model (RZWQM) was made available for application and has been used for crop growth, effects of management, and environmental impact under a variety of situations such as: Midwest and Colorado cropping systems, tile drainage in Iowa, basin irrigation, manure management in Colorado and Arkansas, and water stress responses in Colorado. A user-friendly interface is being marketed commercially.
- Turf professionals recognize that chemicals used to control turfgrass pests can be harmful to plants and animals that live in and around ponds, streams, and lakes surrounding golf courses. Studies by W-188 scientists demonstrated that, when applied according to label, trichlorfon and chlorpyrifos was not found to leach, volatilize, or be removed by clipping.
- W-188 research has contributed significantly to mining company's ability to meet regulatory bonding requirements. In NV, research addressing development of fully coupled flow and geochemical numerical solvers to predict infiltration in mine-altered lands and the fate of such contaminants as cyanide, arsenic, and sulfates. Results are reducing contamination and developing cost-effective closure designs for operating mines.
Publications
2001 PUBLICATIONS:
Abbaspour, K. C., A. Kohler, J.
imunek, M. Fritsch, and R. Schulin, Application of a two-dimensional model to simulate flow and transport in a macroporous agricultural field with tile drains, European J. of Soil Sci., 52(3), 433-447, 2001.
Ahuja, L.R., L. Ma and T.A. Howell (eds.) 2002. Agricultural System Models in Field Research and Technology Transfer, CRC Press, Boca Raton, FL. In press.
Ahuja, L.R., T.R. Green, R.H. Erskine, J.C. Ascough II, L. Ma, G.H. Dunn and M.J. Shaffer, 2002. Topographic analysis, scaling, and models to evaluate spatial/temporal variability of landscape processes and management, In: Agricultural System Models in Field Research and Technology Transfer, Ahuja et al. (eds.), CRC Press, Boca Raton, FL, 6 pp. In press.
Al-Jabri, S.A., Horton, R., and Jaynes, D.B. 2001. Measurement of soil hydraulic and chemical transport properties. p. 105-108. In 2nd International Symposium Preferential Flow. Honolulu, HI. Jan. 3-5, 2001. ASAE, St Joseph, MI.
Arya, L. M., E. L. Pulver, and M. Th. van Genuchten. 2000. Economic, environmental and natural resource benefits of plastic shelters in vegetable production in a humid tropical environment. J. Sustainable Agriculture, 17(2/3):123-143.
Bachmann, J., R. Horton, T. Ren, and R.R. van der Ploeg. 2001. Comparison of the thermal properties of four wettable and four water-repellent soils. Soil Sci. Soc. Am. J. 65:1575-1679.
Bachmann, J., R. Horton, and R.R. van der Ploeg. 2001. Isothermal and nonisothermal evaporation from four sandy soils of different water repellency. Soil Sci. Soc. Am. J. 65:1599-1607.
Bakhsh, A., T.S. Colvin, D.B. Jaynes, R.S. Kanwar, and U.S. Tim. 2000. Using soil attributes and GIS for interpretation of spatial variability in yield. Trans. ASAE. 43:819-828.
Bakhsh, A., Kanwar, R.S., Jaynes, D.B., Colvin, T.S., and Ahuja, L.R. 2001. Preferential flow effects on NO3-N losses with tile flow. p. 41-44. In 2nd International Symposium Preferential Flow. Honolulu, HI. Jan. 3-5, 2001. ASAE, St Joseph, MI.
Bakhsh, A., R.S. Kanwar, D.B. Jaynes, T.S. Colvin, and L.R. Ahuja. 2001. Simulating effects of variable nitrogen application rates on corn yields and NO3-N losses in subsurface drain water. Trans. ASAE. 44:269-276.
Barnes, P., G. Kluitenberg, and J. Ham. 2001. Soil moisture monitoring in the Black Vermillion watershed. p. 9-12. In J. C. Ascough II and D. C. Flanagan (ed.) Soil erosion research for the 21st century. Proc. Int. Symp., Honolulu, HI. 3-5 Jan. 2001. American Society of Agricultural Engineers, St. Joseph, MI.
Bittelli, M., M. Flury, G.S. Campbell, and E.J. Nichols. 2001. Reduction of transpiration through foliar application of Chitosan. Agric. For. Meteorol., 107: 167-175.
Bradford, S. A., and L. M. Abriola. 2001. Dissolution of residual tetrachloroethylene in fractional wettability porous media: Incorporation of interfacial area estimates. Water Resour. Res. 37:1183-1195.
Bradley, E. F., B. E. Clothier, O. T. Denmead, D. A. de Vries, P. W. Ford, G. J. Kluitenberg, J. H. Knight, P. A. C. Raats, D. E. Smiles, R. T. Waechter, I. White, E. G. Youngs. 2001. The environmental mechanic. Aust. J. Soil Res. 39:649-681.
Bristow, K. L., G. J. Kluitenberg, C. J. Goding, and T. S. Fitzgerald. 2001. A small multi-needle probe for measuring soil thermal properties, water content and electrical conductivity. Comput. Electron. Agric. 31:265-280.
Brown, P.W., C.F. Mancino, M.H. Young, T.L. Thompson, P.J. Wierenga and D.M. Kopec. 2001. Penman Monteith crop coefficients for use with desert turf systems. Crop Science 41:1197-1206.
Carrillo, M.L., J. Letey, and S.R. Yates. 2000. Unstable water flow in layered soil I: The effects of a stable water repellent layer. Soil Science Society of America Journal 64:450?455.
Carrillo, M.L., Letey, J. and Yates, S.R. 2000. Unstable water flow in layered soil II: The effects of an unstable water repellent layer. Soil Science Society of America Journal. 64:456?460.
Casey, F.X.M., and J.
imunek. 2001. Inverse Analyses of the Transport of Chlorinated Hydrocarbons Subject to Sequential Transformation Reactions. J. Environ. Qual. 30:1354-1360.
Casey, F.X.M., and N.E. Derby. 2002. Improved Design for an Automated Tension Infiltrometer. Soil Sci. Soc. Am. J. 66 (Jan/Feb).
Casey, F.X.M. 2001. Long-term Water Quality under Irrigated Agriculture: Observations and Trends. North Dakota State University, Irrigation Research Extension Magazine: WaterSpouts (June).
Casey, F.X.M., N.E. Derby, D.D. Steele, R.E. Knighton, and E.C. Stegman. 2001. Initiation of irrigation and the long-term impacts and trends in subsurface water quality. J. Environ. Qual. Submitted.
Casey, F.X.M. 2001. A Novel Method for Field-scale Solute Transport Prediction: 1) Method Development. Water Resour. Res. Submitted.
Casey, F.X.M., N.E. Derby, and D.D. Steele. 2001. A Novel Method for Field-scale Solute Transport Prediction: 2) Method Evaluation. Water Resour. Res. Submitted.
Chu, Y., Y. Jin, M. Flury and M.V. Yates. 2001. Mechanisms of virus removal during transport in unsaturated porous media. Water Resour. Res., 37: 253{263.
Colvin, T.S., Jaynes, D.B., Kaspar, T.C., James, D.E., and Meek, D.W. 2001. Yield certainty with plots or fields. In 5th Int. Conf. Precision Farming. July 16-19-2000. Minneapolis, MN. CD-ROM. ASA-CSSA-SSSA, Madison, WI.
Das, B. S., R. S. Govindaraju, G. J. Kluitenberg, A. J. Valocchi, and J. M. Wraith. 2002. Theory and applications of time moment analysis to study the fate of reactive solutes in soil. In R. S. Govindaraju (ed.) Stochastic methods in subsurface contaminant hydrology. American Society of Civil Engineering. In press.
Dekker, S.C., W. Bouten and M.G. Schaap. 2001. Use of artificial neural networks to improve predictions of a deterministic forest transpiration model. Journal of Hydrology. 246:197-208.
Dungan, R., J. Gan and S.R. Yates. 2001. Effect of temperature, organic amendment rate, and moisture content on the degradation of 1,3?dichloropropene in soil, Pesticide Management Science 57:1?7.
Edmunds, W.M. and S.W.Tyler, Unsaturated zones as archives of paleoclimate: Towards a new proxy for continental regions. Hydrogeology Journal. In press.
Erskine, R.H., T.R. Green, and J.A. Ramirez. 2001. Effects of digital elevation model resolution and accuracy on terrain analyses, Eos, Transactions, Amer Geophys Union, 82(20):S158.
Erskine, R.H, T.R. Green and G.H. Dunn. 2001. GPS/GIS methods for collecting and analyzing grain and forage data, Proc. 2001 ESRI Southwestern User Group Meeting, Tucson, AZ, October 23-25, 2001, 9 pp. (CD-ROM).
Evett, S.R. 2001. Measuring soil water by time domain reflectometry. Accepted for publication In The Encyclopedia of Water Science, Dekker.
Evett, S.R. 2001. Measuring soil water by neutron thermalization. Accepted for publication In The Encyclopedia of Water Science, Dekker.
Evett, S.R., N. Ibragimov, B. Kamilov, Y. Esanbekov, M. Sarimsakov, J. Shadmanov, R. Mirhashimov, R. Musaev, T. Radjabov, and B. Muhammadiev. 2002. Soil moisture neutron probe calibration and use in five soils of Uzbekistan. Accepted for the Proceedings of the 17th World Congress of Soil Science, August 14-21.
Evett, S., J-P Laurent, P. Cepuder, and C. Hignett. 2002. Neutron scattering, capacitance, and TDR soil water content measurements compared on four continents. Accepted for the Proceedings of the 17th World Congress of Soil Science, August 14-21.
Evett, S.R. 2002. Water and Energy Balances at Soil-Plant-Atmosphere Interfaces. Pp. 127-188 In Arthur A. Warrick (ed.) The Soil Physics Companion. CRC Press LLC, Boca Raton, FL.
Evett, S.R., B.B. Ruthardt, S.T. Kottkamp, T.A. Howell, A.D. Schneider, and J.A. Tolk. Accuracy and precision of soil water measurements by neutron, capacitance, and TDR methods. Accepted for the Proceedings of the 17th World Congress of Soil Science, August 14-21, 2002.
Evett, S.R., B.B. Ruthardt, S.T. Kottkamp, J.A. Tolk, and T.A. Howell. 2001. Profiling soil water probes compared in three soils. Agron. Abstr. (CD-ROM)
Ewing, R.P. and B. Berkowitz. 2001. Stochastic pore-scale growth models of DNAPL migration in porous media. Adv. Water Resour. 24:309-323.
Feng, G., J. Letey, L. Wu. 2001. Water ponding depths affect temporal infiltration rates in a water-repellent sand. . Soil Sci. Soc. Am. J. 65:315-320.
Fennemore, G.G., A. Davis, L. Goss and A.W. Warrick. 2000. A rapid screening-level method to optimize location of infiltration pond. Ground Water 39:230-238.
Flury, M. and Gimmi, T. 2002. Solute diffusion. In: J. H. Dane and G. C. Topp (Editors),
Methods of Soil Analysis, Part 1, Physical Methods. 3rd edn. American Society of Agronomy, Madison, WI, In press.
Gan, J., Q. Wang, S. Yates, W. Koskinen, and W. Jury, 2001. Dehalogenation of Chloroacetamide Herbicides by Thiosulfate Salts Proc. Nat. Acad. Sci. Submitted.
Gan, J., N.E. Megonnell and S.R. Yates. 2001. Adsorption and catalytic hydrolysis of methyl bromide and methyl iodide on activated carbons. Atmospheric Environment 35:941?947.
Goncalves, M.C., F.J. Leij, and M.G. Schaap. 2001. Pedotransfer functions for solute transport parameters. European Journal of Soil Science 52(4):563-574.
Gao, F., Y. Jin, S.R. Yates, S.K. Papiernik, M.A. Anderson, and M.V.Yates. 2001. Theory and laboratory study of a tall passive chamber for measuring gas fluxes at soil surface, J. Air & Waste Management Assoc. 51:49?59.
This is a partial List
Complete List can be found at: http://www.soilsci.ndsu.nodak.edu/w188
Abbaspour, K. C., A. Kohler, J.
imunek, M. Fritsch, and R. Schulin, Application of a two-dimensional model to simulate flow and transport in a macroporous agricultural field with tile drains, European J. of Soil Sci., 52(3), 433-447, 2001.
Ahuja, L.R., L. Ma and T.A. Howell (eds.) 2002. Agricultural System Models in Field Research and Technology Transfer, CRC Press, Boca Raton, FL. In press.
Ahuja, L.R., T.R. Green, R.H. Erskine, J.C. Ascough II, L. Ma, G.H. Dunn and M.J. Shaffer, 2002. Topographic analysis, scaling, and models to evaluate spatial/temporal variability of landscape processes and management, In: Agricultural System Models in Field Research and Technology Transfer, Ahuja et al. (eds.), CRC Press, Boca Raton, FL, 6 pp. In press.
Al-Jabri, S.A., Horton, R., and Jaynes, D.B. 2001. Measurement of soil hydraulic and chemical transport properties. p. 105-108. In 2nd International Symposium Preferential Flow. Honolulu, HI. Jan. 3-5, 2001. ASAE, St Joseph, MI.
Arya, L. M., E. L. Pulver, and M. Th. van Genuchten. 2000. Economic, environmental and natural resource benefits of plastic shelters in vegetable production in a humid tropical environment. J. Sustainable Agriculture, 17(2/3):123-143.
Bachmann, J., R. Horton, T. Ren, and R.R. van der Ploeg. 2001. Comparison of the thermal properties of four wettable and four water-repellent soils. Soil Sci. Soc. Am. J. 65:1575-1679.
Bachmann, J., R. Horton, and R.R. van der Ploeg. 2001. Isothermal and nonisothermal evaporation from four sandy soils of different water repellency. Soil Sci. Soc. Am. J. 65:1599-1607.
Bakhsh, A., T.S. Colvin, D.B. Jaynes, R.S. Kanwar, and U.S. Tim. 2000. Using soil attributes and GIS for interpretation of spatial variability in yield. Trans. ASAE. 43:819-828.
Bakhsh, A., Kanwar, R.S., Jaynes, D.B., Colvin, T.S., and Ahuja, L.R. 2001. Preferential flow effects on NO3-N losses with tile flow. p. 41-44. In 2nd International Symposium Preferential Flow. Honolulu, HI. Jan. 3-5, 2001. ASAE, St Joseph, MI.
Bakhsh, A., R.S. Kanwar, D.B. Jaynes, T.S. Colvin, and L.R. Ahuja. 2001. Simulating effects of variable nitrogen application rates on corn yields and NO3-N losses in subsurface drain water. Trans. ASAE. 44:269-276.
Barnes, P., G. Kluitenberg, and J. Ham. 2001. Soil moisture monitoring in the Black Vermillion watershed. p. 9-12. In J. C. Ascough II and D. C. Flanagan (ed.) Soil erosion research for the 21st century. Proc. Int. Symp., Honolulu, HI. 3-5 Jan. 2001. American Society of Agricultural Engineers, St. Joseph, MI.
Bittelli, M., M. Flury, G.S. Campbell, and E.J. Nichols. 2001. Reduction of transpiration through foliar application of Chitosan. Agric. For. Meteorol., 107: 167-175.
Bradford, S. A., and L. M. Abriola. 2001. Dissolution of residual tetrachloroethylene in fractional wettability porous media: Incorporation of interfacial area estimates. Water Resour. Res. 37:1183-1195.
Bradley, E. F., B. E. Clothier, O. T. Denmead, D. A. de Vries, P. W. Ford, G. J. Kluitenberg, J. H. Knight, P. A. C. Raats, D. E. Smiles, R. T. Waechter, I. White, E. G. Youngs. 2001. The environmental mechanic. Aust. J. Soil Res. 39:649-681.
Bristow, K. L., G. J. Kluitenberg, C. J. Goding, and T. S. Fitzgerald. 2001. A small multi-needle probe for measuring soil thermal properties, water content and electrical conductivity. Comput. Electron. Agric. 31:265-280.
Brown, P.W., C.F. Mancino, M.H. Young, T.L. Thompson, P.J. Wierenga and D.M. Kopec. 2001. Penman Monteith crop coefficients for use with desert turf systems. Crop Science 41:1197-1206.
Carrillo, M.L., J. Letey, and S.R. Yates. 2000. Unstable water flow in layered soil I: The effects of a stable water repellent layer. Soil Science Society of America Journal 64:450?455.
Carrillo, M.L., Letey, J. and Yates, S.R. 2000. Unstable water flow in layered soil II: The effects of an unstable water repellent layer. Soil Science Society of America Journal. 64:456?460.
Casey, F.X.M., and J.
imunek. 2001. Inverse Analyses of the Transport of Chlorinated Hydrocarbons Subject to Sequential Transformation Reactions. J. Environ. Qual. 30:1354-1360.
Casey, F.X.M., and N.E. Derby. 2002. Improved Design for an Automated Tension Infiltrometer. Soil Sci. Soc. Am. J. 66 (Jan/Feb).
Casey, F.X.M. 2001. Long-term Water Quality under Irrigated Agriculture: Observations and Trends. North Dakota State University, Irrigation Research Extension Magazine: WaterSpouts (June).
Casey, F.X.M., N.E. Derby, D.D. Steele, R.E. Knighton, and E.C. Stegman. 2001. Initiation of irrigation and the long-term impacts and trends in subsurface water quality. J. Environ. Qual. Submitted.
Casey, F.X.M. 2001. A Novel Method for Field-scale Solute Transport Prediction: 1) Method Development. Water Resour. Res. Submitted.
Casey, F.X.M., N.E. Derby, and D.D. Steele. 2001. A Novel Method for Field-scale Solute Transport Prediction: 2) Method Evaluation. Water Resour. Res. Submitted.
Chu, Y., Y. Jin, M. Flury and M.V. Yates. 2001. Mechanisms of virus removal during transport in unsaturated porous media. Water Resour. Res., 37: 253{263.
Colvin, T.S., Jaynes, D.B., Kaspar, T.C., James, D.E., and Meek, D.W. 2001. Yield certainty with plots or fields. In 5th Int. Conf. Precision Farming. July 16-19-2000. Minneapolis, MN. CD-ROM. ASA-CSSA-SSSA, Madison, WI.
Das, B. S., R. S. Govindaraju, G. J. Kluitenberg, A. J. Valocchi, and J. M. Wraith. 2002. Theory and applications of time moment analysis to study the fate of reactive solutes in soil. In R. S. Govindaraju (ed.) Stochastic methods in subsurface contaminant hydrology. American Society of Civil Engineering. In press.
Dekker, S.C., W. Bouten and M.G. Schaap. 2001. Use of artificial neural networks to improve predictions of a deterministic forest transpiration model. Journal of Hydrology. 246:197-208.
Dungan, R., J. Gan and S.R. Yates. 2001. Effect of temperature, organic amendment rate, and moisture content on the degradation of 1,3?dichloropropene in soil, Pesticide Management Science 57:1?7.
Edmunds, W.M. and S.W.Tyler, Unsaturated zones as archives of paleoclimate: Towards a new proxy for continental regions. Hydrogeology Journal. In press.
Erskine, R.H., T.R. Green, and J.A. Ramirez. 2001. Effects of digital elevation model resolution and accuracy on terrain analyses, Eos, Transactions, Amer Geophys Union, 82(20):S158.
Erskine, R.H, T.R. Green and G.H. Dunn. 2001. GPS/GIS methods for collecting and analyzing grain and forage data, Proc. 2001 ESRI Southwestern User Group Meeting, Tucson, AZ, October 23-25, 2001, 9 pp. (CD-ROM).
Evett, S.R. 2001. Measuring soil water by time domain reflectometry. Accepted for publication In The Encyclopedia of Water Science, Dekker.
Evett, S.R. 2001. Measuring soil water by neutron thermalization. Accepted for publication In The Encyclopedia of Water Science, Dekker.
Evett, S.R., N. Ibragimov, B. Kamilov, Y. Esanbekov, M. Sarimsakov, J. Shadmanov, R. Mirhashimov, R. Musaev, T. Radjabov, and B. Muhammadiev. 2002. Soil moisture neutron probe calibration and use in five soils of Uzbekistan. Accepted for the Proceedings of the 17th World Congress of Soil Science, August 14-21.
Evett, S., J-P Laurent, P. Cepuder, and C. Hignett. 2002. Neutron scattering, capacitance, and TDR soil water content measurements compared on four continents. Accepted for the Proceedings of the 17th World Congress of Soil Science, August 14-21.
Evett, S.R. 2002. Water and Energy Balances at Soil-Plant-Atmosphere Interfaces. Pp. 127-188 In Arthur A. Warrick (ed.) The Soil Physics Companion. CRC Press LLC, Boca Raton, FL.
Evett, S.R., B.B. Ruthardt, S.T. Kottkamp, T.A. Howell, A.D. Schneider, and J.A. Tolk. Accuracy and precision of soil water measurements by neutron, capacitance, and TDR methods. Accepted for the Proceedings of the 17th World Congress of Soil Science, August 14-21, 2002.
Evett, S.R., B.B. Ruthardt, S.T. Kottkamp, J.A. Tolk, and T.A. Howell. 2001. Profiling soil water probes compared in three soils. Agron. Abstr. (CD-ROM)
Ewing, R.P. and B. Berkowitz. 2001. Stochastic pore-scale growth models of DNAPL migration in porous media. Adv. Water Resour. 24:309-323.
Feng, G., J. Letey, L. Wu. 2001. Water ponding depths affect temporal infiltration rates in a water-repellent sand. . Soil Sci. Soc. Am. J. 65:315-320.
Fennemore, G.G., A. Davis, L. Goss and A.W. Warrick. 2000. A rapid screening-level method to optimize location of infiltration pond. Ground Water 39:230-238.
Flury, M. and Gimmi, T. 2002. Solute diffusion. In: J. H. Dane and G. C. Topp (Editors),
Methods of Soil Analysis, Part 1, Physical Methods. 3rd edn. American Society of Agronomy, Madison, WI, In press.
Gan, J., Q. Wang, S. Yates, W. Koskinen, and W. Jury, 2001. Dehalogenation of Chloroacetamide Herbicides by Thiosulfate Salts Proc. Nat. Acad. Sci. Submitted.
Gan, J., N.E. Megonnell and S.R. Yates. 2001. Adsorption and catalytic hydrolysis of methyl bromide and methyl iodide on activated carbons. Atmospheric Environment 35:941?947.
Goncalves, M.C., F.J. Leij, and M.G. Schaap. 2001. Pedotransfer functions for solute transport parameters. European Journal of Soil Science 52(4):563-574.
Gao, F., Y. Jin, S.R. Yates, S.K. Papiernik, M.A. Anderson, and M.V.Yates. 2001. Theory and laboratory study of a tall passive chamber for measuring gas fluxes at soil surface, J. Air & Waste Management Assoc. 51:49?59.
This is a partial List
Complete List can be found at: http://www.soilsci.ndsu.nodak.edu/w188