HR: 0830h
AN: H11G-0921    [PDF]
TI: MIM Simulation of Cl$^{-}$ and B Transport: Comparison with Measured Data from an Irrigated Field
AU: * Vaughan, P J
EM: pvaughan@ussl.ars.usda.gov
AF: George E. Brown, Jr. Salinity Lab. USDA-ARS, 450 W Big Springs Road, Riverside, CA 92507 United States
AU: Suarez, D L
EM: dsuarez@ussl.ars.usda.gov
AF: George E. Brown, Jr. Salinity Lab. USDA-ARS, 450 W Big Springs Road, Riverside, CA 92507 United States
AB: The mobile-immobile water (MIM) model of solute transport can provide an improved representation of solute transport in soils especially for intact soil samples or field soils. The Unsatchem model of multicomponent solute transport was upgraded to include the MIM model. A field-based test of the MIM model consisted of running Unsatchem for 45 locations within a 65 ha field in the San Joaquin Valley. Soil sampling was done for 6 depths (0-1.8 m), all locations, five different sampling periods starting in November, 1995 and ending in November, 1997. Cl$^{-}$ transport was calculated for both standard uniform flow (UFM) and MIM models. The MIM model parameters, $\omega$, the transfer coefficient, and $\theta$$_{im}$, the immobile water content, were varied systematically to determine their influence on the match between the model results and measured resident chloride concentrations. The MIM model performed better than UFM with the best match occurring for the highest $\theta$$_{im}$ and 10$^{-4}$$<$=$\omega$$<$=10$^{-3}$.
DE: 1065 Trace elements (3670)
DE: 1806 Chemistry of fresh water
DE: 1818 Evapotranspiration
DE: 1842 Irrigation
DE: 1875 Unsaturated zone
SC: Hydrology [H]
MN: 2003 Fall Meeting