HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Emmerich, W. E. Articles by Shirley, E. D. Search for Related Content PubMed Articles by Emmerich, W. E. Articles by Shirley, E. D. Agricola Articles by Emmerich, W. E. Articles by Shirley, E. D.

Comparison of Lumped and Distributed Models for Chemical Transport by Surface Runoff

USDA-ARS, Aridland Watershed Management Research Unit, 2000 E. Allen Rd., Tucson, AZ 85719.

^* Corresponding author.

ABSTRACT

A simple, complete mixing model is used to evaluate the degree of distortion involved in modeling chemical exchange and transport at the soil surface as a lumped rather than a distributed process. A complete mixing model was coupled to the kinematic cascade model, KINEROS, to provide a distributed representation of chemical exchange and transport. A lumped model was developed by ignoring spatial variations of chemical concentration in overland flow and in the mixing zone. Chemical concentration and transport predicted by the alternative approaches were evaluated for total transport, arrival time, peak concentration time, and peak concentration. Total chemical transport was virtually unaffected by model form. However, significant differences were found in arrival and peak concentration times as well as peak concentrations when chemical was placed only in the upper plane of a two plane cascade. The lumped model predicted significantly lower peak chemical concentrations and arrival times that were too short. A lumped model provides a good approximation for transport from a single plane, but caution should be used when a lumped model is used to describe chemical exchange and transport on a cascade of planes.

Contribution of USDA-ARS, Aridland Watershed Management Research Unit.

Received for publication June 22, 1988.

This article has been cited by other articles:

				A. Furman Modeling Coupled Surface-Subsurface Flow Processes: A Review Vadose Zone J., May 27, 2008; 7(2): 741 - 756. [Abstract] [Full Text] [PDF]