By Seann Mischa Reed, Ph. Use of simplified process models is justified because there are large uncertainties involved with the specification of soil hydraulic properties and in quantifying rainfall. Representative soil hydraulic properties are assigned based on USDA texture class.
Spatial complexity is varied in three different ways.
In the two-layer conceptual soil model, the top layer controls direct runoff, but the bottom layer serves as an important control on how much water evaporates and how much water percolates to the groundwater reservoir. When the spatial variability of surface texture is reduced through resampling of soil properties, model performance decreases. Further simulations should be made to verify these conclusions. The highlighted links that follow are connected to Adobe pdf files of the corresponding material. To view them you must have the Adobe Acrobat Reader 3.0.