Propagation of Uncertainty in Solute Transport Simulations.

Soil salinity reduces crop production on about 50% of irrigated lands worldwide.  One roadblock to increased use of advanced computer simulation tools for better managing irrigation water and soil salinity is that the models usually do not provide an estimate of the uncertainty in model predictions, which can be substantial.  In this work, we investigate methods for putting confidence bounds on simulations of solute leaching in soils.  Uncertainties in model parameters are propagated through simulation model predictions using Monte Carlo simulation.  Generalized sensitivity analyses indicate which parameters are most significant for quantifying uncertainty.  The simulation results are compared with experimentally observed transport variability in a number of large, replicated lysimeters.