Detailed Characterization of Solute Transport in a Heterogeneous Field Soil

ABSTRACT There is a necessity for improved physical understanding of solute transport processes in heterogeneous soil systems. In situ nondestructive techniques like time domain reflectometry (TDR) and fiber optic miniprobes (FOMPs) permit the collection of unique measurements of solute transport pr...

Full description

Saved in:
Bibliographic Details
Published in:Journal of environmental quality 2001-03, Vol.30 (2), p.573-583
Main Authors: Garrido, Fernando, Ghodrati, Masoud, Campbell, Chris G., Chendorain, Michael
Format: Article
Language:English
Subjects:
Applied sciences
Biological and physicochemical properties of pollutants. Interaction in the soil
Earth sciences
Earth, ocean, space
Engineering and environment geology. Geothermics
Exact sciences and technology
Fiber Optic Technology
Forecasting
Hydrology
Hydrology. Hydrogeology
Models, Theoretical
Optical Fibers
Pollution
Pollution, environment geology
Soil and sediments pollution
Soil Pollutants - analysis
Solubility
Water Movements
Water Pollutants - analysis
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:ABSTRACT There is a necessity for improved physical understanding of solute transport processes in heterogeneous soil systems. In situ nondestructive techniques like time domain reflectometry (TDR) and fiber optic miniprobes (FOMPs) permit the collection of unique measurements of solute transport processes in soils for the purposes of model development and validation. This study examined the application of TDR and FOMPs to measure solute transport at various points laterally and at two depths in a heterogeneous clay‐loam soil. A miscible displacement experiment was performed at a constant irrigation flux to examine the applicability of these probes to field soils. In their first application to a field soil, the FOMPs were successfully calibrated and performed well in measuring solute breakthrough curves. Two flow regimes were identified in the soil profile, the first where lateral spreading of the solute occurred in the surface horizon, followed by convergence into preferential flow pathways in the second transport zone. The measured transport response was heterogeneous with at least two identifiable vertical flow phases. It was demonstrated using transfer function modeling and data from a corresponding laboratory study that the FOMPs were measuring the slower phase, while the TDR probes captured a composite of the fast and slow phases. The combination of these two techniques may be a means to separate solute transport phases in heterogeneous media and relate laboratory column results to field studies.
ISSN:0047-2425
1537-2537
DOI:10.2134/jeq2001.302573x