HR: 13:45h
AN: H13D-02    [Abstracts]
TI: Equivalence of Hydraulic Functions and Its Implication on Upscaling for Steady State Flux and Surface Soil Moisture in Heterogeneous Soils
AU: * Zhu, J
EM: Jianting.Zhu@dri.edu
AF: Desert Research Institute, Division of Hydrologic Sciences, 755 E. Flamingo Road, Las Vegas, NV 89119 United States
AB: Soil hydraulic properties at large scales (e.g., remote sensing footprints) are important for land-atmosphere interaction and general circulation models or other applications. This study investigates two major issues involving soil hydraulic properties: (1) hydraulic parameter equivalence among some of the more commonly used soil hydraulic conductivity functions, and (2) its implication in upscaling of hydraulic properties to large scales for steady-state flow in heterogeneous soils. We first establish parameter equivalence among the conductivity functions based on hydrologic process equivalence. We propose two important equivalence criteria based on hydraulic behavior equivalence. Our approach forces both the predicted flux across the soil surface and the surface soil moisture content to be the same for the different hydraulic property functions. We selected these two hydrologic quantities for the equivalence purpose since they are important state variables in upscaling of hydrologic processes from local scale to footprint scale. Next we investigate the significance of parameter equivalence on upscaling schemes for the hydraulic parameters to allow predictions of the ensemble characteristics for steady-state flow at large scales.
DE: 1833 Hydroclimatology
DE: 1866 Soil moisture
DE: 1869 Stochastic processes
DE: 1875 Unsaturated zone
SC: Hydrology [H]
MN: 2005 Joint Assembly