Comparison of flux and resident concentrations in macroporous field soils

Dong Ju Kim, J. Feyen

Research output: Contribution to journalArticle

6 Citations (Scopus)

Abstract

In many solute transport studies, either the flux or the resident concentration is used. In some cases, however, the transport parameters obtained from different concentration modes may not be identical, especially for soils having preferential pathways. In this study we investigated differences in the transport parameters between flux and resident concentrations by performing laboratory solute displacement experiments on a number of structured field soils. Breakthrough curves (BTCs) of flux and resident concentrations for a pulse injection of 10 g/L CaCl2 solution were monitored simultaneously at the bottom and middle of soil columns using an EC-meter and time domain reflectometry (TDR) probes, respectively. Transport parameters were then obtained by fitting the convective log-normal transfer function (CLT) model to the observed BTC data and compared for different concentration modes. Flux concentrations predicted from the parameters of resident concentrations based on the CLT model were also compared with the observed BTC data. Comparison of transport parameters between the flux and resident concentrations showed substantial differences caused by preferential movement of solute through soil macropores. The predicted flux concentration BTCs also differed greatly from the observed BTCs in peak and travel time. This suggests that for structured soils having preferential flow, the TDR-measured resident concentrations are not representative of solute transport in the soil macropores but are primarily in the soil matrix region, and use of TDR for monitoring resident concentrations in such soils becomes limited.

Original languageEnglish
Pages (from-to)616-623
Number of pages8
JournalSoil Science
Volume165
Issue number8
Publication statusPublished - 2000 Sep 23

Fingerprint

breakthrough curve
time domain reflectometry
soil transport processes
soil
macropore
macropores
solute transport
transfer function
solute
preferential flow
soil column
comparison
travel time
travel
solutes
probe
parameter
matrix
injection
monitoring

Keywords

  • Breakthrough curve
  • Convective lognormal transfer function
  • Flux concentration
  • Resident concentration
  • Solute transport
  • Structured soil

ASJC Scopus subject areas

  • Soil Science
  • Earth-Surface Processes

Cite this

Comparison of flux and resident concentrations in macroporous field soils. / Kim, Dong Ju; Feyen, J.

In: Soil Science, Vol. 165, No. 8, 23.09.2000, p. 616-623.

Research output: Contribution to journalArticle

@article{d637f3d02c4e4e488aad9b3610af20a6,
title = "Comparison of flux and resident concentrations in macroporous field soils",
abstract = "In many solute transport studies, either the flux or the resident concentration is used. In some cases, however, the transport parameters obtained from different concentration modes may not be identical, especially for soils having preferential pathways. In this study we investigated differences in the transport parameters between flux and resident concentrations by performing laboratory solute displacement experiments on a number of structured field soils. Breakthrough curves (BTCs) of flux and resident concentrations for a pulse injection of 10 g/L CaCl2 solution were monitored simultaneously at the bottom and middle of soil columns using an EC-meter and time domain reflectometry (TDR) probes, respectively. Transport parameters were then obtained by fitting the convective log-normal transfer function (CLT) model to the observed BTC data and compared for different concentration modes. Flux concentrations predicted from the parameters of resident concentrations based on the CLT model were also compared with the observed BTC data. Comparison of transport parameters between the flux and resident concentrations showed substantial differences caused by preferential movement of solute through soil macropores. The predicted flux concentration BTCs also differed greatly from the observed BTCs in peak and travel time. This suggests that for structured soils having preferential flow, the TDR-measured resident concentrations are not representative of solute transport in the soil macropores but are primarily in the soil matrix region, and use of TDR for monitoring resident concentrations in such soils becomes limited.",
keywords = "Breakthrough curve, Convective lognormal transfer function, Flux concentration, Resident concentration, Solute transport, Structured soil",
author = "Kim, {Dong Ju} and J. Feyen",
year = "2000",
month = "9",
day = "23",
language = "English",
volume = "165",
pages = "616--623",
journal = "Soil Science",
issn = "0038-075X",
publisher = "Lippincott Williams and Wilkins",
number = "8",

}

TY - JOUR

T1 - Comparison of flux and resident concentrations in macroporous field soils

AU - Kim, Dong Ju

AU - Feyen, J.

PY - 2000/9/23

Y1 - 2000/9/23

N2 - In many solute transport studies, either the flux or the resident concentration is used. In some cases, however, the transport parameters obtained from different concentration modes may not be identical, especially for soils having preferential pathways. In this study we investigated differences in the transport parameters between flux and resident concentrations by performing laboratory solute displacement experiments on a number of structured field soils. Breakthrough curves (BTCs) of flux and resident concentrations for a pulse injection of 10 g/L CaCl2 solution were monitored simultaneously at the bottom and middle of soil columns using an EC-meter and time domain reflectometry (TDR) probes, respectively. Transport parameters were then obtained by fitting the convective log-normal transfer function (CLT) model to the observed BTC data and compared for different concentration modes. Flux concentrations predicted from the parameters of resident concentrations based on the CLT model were also compared with the observed BTC data. Comparison of transport parameters between the flux and resident concentrations showed substantial differences caused by preferential movement of solute through soil macropores. The predicted flux concentration BTCs also differed greatly from the observed BTCs in peak and travel time. This suggests that for structured soils having preferential flow, the TDR-measured resident concentrations are not representative of solute transport in the soil macropores but are primarily in the soil matrix region, and use of TDR for monitoring resident concentrations in such soils becomes limited.

AB - In many solute transport studies, either the flux or the resident concentration is used. In some cases, however, the transport parameters obtained from different concentration modes may not be identical, especially for soils having preferential pathways. In this study we investigated differences in the transport parameters between flux and resident concentrations by performing laboratory solute displacement experiments on a number of structured field soils. Breakthrough curves (BTCs) of flux and resident concentrations for a pulse injection of 10 g/L CaCl2 solution were monitored simultaneously at the bottom and middle of soil columns using an EC-meter and time domain reflectometry (TDR) probes, respectively. Transport parameters were then obtained by fitting the convective log-normal transfer function (CLT) model to the observed BTC data and compared for different concentration modes. Flux concentrations predicted from the parameters of resident concentrations based on the CLT model were also compared with the observed BTC data. Comparison of transport parameters between the flux and resident concentrations showed substantial differences caused by preferential movement of solute through soil macropores. The predicted flux concentration BTCs also differed greatly from the observed BTCs in peak and travel time. This suggests that for structured soils having preferential flow, the TDR-measured resident concentrations are not representative of solute transport in the soil macropores but are primarily in the soil matrix region, and use of TDR for monitoring resident concentrations in such soils becomes limited.

KW - Breakthrough curve

KW - Convective lognormal transfer function

KW - Flux concentration

KW - Resident concentration

KW - Solute transport

KW - Structured soil

UR - http://www.scopus.com/inward/record.url?scp=0033812498&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0033812498&partnerID=8YFLogxK

M3 - Article

AN - SCOPUS:0033812498

VL - 165

SP - 616

EP - 623

JO - Soil Science

JF - Soil Science

SN - 0038-075X

IS - 8

ER -