Robust estimation of the generalized solute transfer function parameters

摘要: A method is presented to mathematically characterize a wide range of solute transport processes in soils from time-domain-reflectometry (TDR)-based breakthrough curve (BTC) measurements. To do this, we combined the flexible generalized transfer function model (GTF) with definition time normalized resident concentrations C-n*. The GTF four-parameter able describe both convection-dispersive (CD) and stochastic-convective (SC) process dispersion soil. In addition, it allows other typical for heterogeneous be modeled. obtain robust estimations parameters, closed-form expressions C-n* temporal moments were defined. These allow parameters estimated TDR-based BTCs without relying on problematic probe calibrations mass recovery assumptions. Since model, robustness parameterization procedure. was tested by fitting numerically generated, error-contaminated BTCs. Using least-square optimization technique, estimates could obtained TDR observations at two different soil depths. Application proposed also real undisturbed sandy subsoil compared convective lognormal (CLT) CD models. For this case, shown that improved greatly goodness prediction offers new powerful tool analyzing nonreactive solutes