Quick Search:    advanced search

GSW Home   GeoRef Home   My GSW Alerts   Contact GSW   About GSW   Journals List   Help

This Article Figures Only Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Kamai, T. Articles by Hopmans, J. W. Search for Related Content GeoRef GeoRef Citation

Design and Numerical Analysis of a Button Heat Pulse Probe for Soil Water Content Measurement

^a Dep. of Land, Air and Water Resources, Univ. of California, 123 Veihmeyer Hall, Davis, CA 95616
^b Dep. of Agronomy, 2702 Throckmorton Plant Sciences Center, Kansas State Univ., Manhattan, KS 66506

Correspondence: ^* Corresponding author (jwhopmans{at}ucdavis.edu).

Received for publication 2 July 2008. Evaluation of a newly designed button heat pulse probe (BHPP) demonstrated the potential for improved soil water content measurements. Compared with the conventional heat pulse probe (HPP), the BHPP does not use needles, but instead consists of a ring-shaped 6-mm-radius heating element and a central thermistor, both embedded in the face of a plastic disk (6 mm thick and 16 mm in diameter). After calibration of the effective heater–thermistor spacing from temperature response measurements in agar, a sensitivity analysis was conducted to demonstrate the potential advantages of the BHPP. Measurement accuracy and robustness of the BHPP were significantly improved compared with the conventional HPP. Errors associated with needle deflection were eliminated by the design, whereas the water content measurement sensitivity was increased by the central placement of the thermistor. We used inverse modeling with a finite-element heat transport model to illustrate the increased sensitivity of the BHPP to soil water content measurements.

Abbreviations: BHPP, button heat pulse probe • HPP, heat pulse probe