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

This Article Figures Only Full Text Free Full Text (PDF) Free Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in ISI Web of Science Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via ISI Web of Science (12) Citing Articles via Google Scholar Google Scholar Articles by Liu, S. Articles by Yeh, T.-C. J. Search for Related Content PubMed Articles by Liu, S. Articles by Yeh, T.-C. J. GeoRef GeoRef Citation Agricola Articles by Liu, S. Articles by Yeh, T.-C. J. Related Collections Water Content Tomography

ORIGINAL RESEARCH

An Integrative Approach for Monitoring Water Movement in the Vadose Zone

^a Burgess & Niple, 5025 E. Washington St., Phoenix, AZ 85034
^b Dep. of Hydrology and Water Resour., John W. Harshbarger Bldg., The Univ. of Arizona, Tucson, AZ 85721
^* Corresponding author (yeh{at}hwr.arizona.edu).

Received 18 July 2003.

Electrical resistivity tomography (ERT), during the past few years, has emerged as a potentially cost-effective, noninvasive tool for imaging changes of moisture content in the vadose zone. The accuracy of ERT surveys, however, has been the subject of debate because of its nonunique inverse solution and spatial variability in the constitutive relation between resistivity and moisture content. In this paper, an integrative inverse approach for ERT, based on a stochastic information fusion concept of Yeh and imnek, was developed to derive the best unbiased estimate of the moisture content distribution. Unlike classical ERT inversion approaches, this new approach assimilates prior information about the geological and moisture content structures in a given geological medium, as well as sparse point measurements of the moisture content, electrical resistivity, and electric potential. Using these types of data and considering the spatial variability of the resistivity–moisture content relation, the new approach directly estimates three-dimensional moisture content distributions instead of simply changes in moisture content in the vadose zone. Numerical experiments were conducted to investigate the effect of uncertainties in the prior information on the estimate. The effects of spatial variability in the constitutive relation were then examined on the interpretation of the change in moisture content, based on the change in electrical resistivity from the ERT survey. Finally, the ability of the integrative approach was tested by directly estimating moisture distributions in three-dimensional, heterogeneous vadose zones. Results show that the integrative approach can produce accurate estimates of the moisture content distributions and that incorporating some measurements of the moisture content is essential to improve the estimate.

Abbreviations: ERT, electrical resistivity tomography

This article has been cited by other articles:

				S. A. Amidu and J. A. Dunbar Geoelectric Studies of Seasonal Wetting and Drying of a Texas Vertisol Vadose Zone J., August 1, 2007; 6(3): 511 - 523. [Abstract] [Full Text] [PDF]

				H. Vereecken, R. Kasteel, J. Vanderborght, and T. Harter Upscaling Hydraulic Properties and Soil Water Flow Processes in Heterogeneous Soils: A Review Vadose Zone J., January 24, 2007; 6(1): 1 - 28. [Abstract] [Full Text] [PDF]