Numerical simulations of water ̄ow and solute transport were used to investigate the e€ect of the recharge (rain/irrigation) at the soil surface on solute spreading and breakthrough in a realistic, three-dimensional, heterogeneous, vadose zone±groundwater ̄ow system. Results of the analyses suggest that smaller recharge at the soil surface increases the relative variability in the response of t...

While inverse parameter estimation techniques for determining key parameters affecting water flow and solute transport are becoming increasingly common in saturated and unsaturated zone studies, their application to practical problems, such as irrigation, have received relatively little attention. In this article, we used the Levenberg–Marquardt optimization algorithm in combination with the HY...

CHAPTER L GENERAL INTRODUCTION 1 [ntroduction I Dissertation Organization 4 References 5 CHAPTER 2. EVALUATION OF A SIMPLE METHOD FOR ESTIMATING SOLUTE TRANSPORT PAR.\>4ETERS: LABORATORY STUDIES 9 Abstract 9 [ntroduction 10 Materials and Methods 13 Results and Discussion 16 Conclusions 22 References 23 CHAPTER 3. A TIME DOMAIN REFLECTOMETRY METHOD TO MEASURE IMMOBILE WATER CONTENT AND MASS EXCH...

Horizontal contaminant transport through unsaturated soil been demonstrated both analytically and experimentally. The water and solute transport equations were solved using the Boltzman transformation, to convert the partial differential equations to ordinary differential equations. The resulted mathematical model was verified using experimental data. A laboratory scale column system was constr...

Most field soils exhibit soil spatial variability as well as soil structure. The challenge is to account adequately for both types of spatial heterogeneity in simulation models. A numerical finite element code was used to compare singleand dual-permeability approaches for modeling variably saturated flow and transport in two-dimensional heterogeneous soil systems. The code was based on the Rich...

this study was reported by Regalado et al. (2003) and Muñoz-Carpena et al. (2005). Volcanic soils exhibit particular physical-chemical properties (i.e., The intensive use of agrichemicals in volcanic agriculstrong and stable natural aggregation and high content of variablecharge minerals) that may influence solute transport. To determine tural fields, as for many other areas of the world, has l...

solute transport in unsaturated porous media can be viewed as a coupled phenomenon with waterand heat transport, together with mechanical behaviour of media. in this paper, solute transport is formulatedmathematically considering heat and water flow in deformable porous media. advection, dispersion anddiffusion of chemical species in the liquid phase are considered. convection and conduction fo...