J. Jpn. Soc. Soil Phys.
No. +*2, p. 3+32 ,**2´µ¶·*ῌ¸¹º**
Measurement of Soil Heat Flux Using a Thermo-moduleToshihiko MOMOSE* and Tatsuaki KASUBUCHI*** Division of Engineering, Saint Mary’s University, Halifax, B-H-C-, Canada** Faculty of Agriculture, Yamagata University, Tsuruoka, 331ῌ2///, Japan
Abstract
Measurement of soil heat ﬂux using a thermo-module was examined. The measuring principle
is almost the same to a traditional heat ﬂux plate method, however, the measurement accuracy ofthe temperature di#erence of the thermo-module is much higher than that of the traditional
thermo-pile. It was considered that the utilization of thermo-module allowed to measure the soilheat ﬂux accurately even under the soil layer of small temperature gradients.

Relation between

the thermo-module output and one-dimensional steady heat ﬂux was examined in agar-gel. As aresult, the thermo-module output was proportional to the heat ﬂux in a wide range.
relation, the soil heat ﬂux in a ﬁeld was determined.

Using thisIn order to conﬁrm the reliability of thethermo-module method, the heat storage ﬂux in soil layer was compared between the thermomodule method and the calorimetric method. Both results corresponded closely. These showedthat the thermo-module method was e#ective as the heat ﬂux meter.
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Soil Science Society of America, Madison, WI.
Liley, P.E. (+32/) : Thermophysical properties.In :Handbook of heat transfer fundamentals, ,ndedn. (eds. W.M. Rohsenow, J.P. Hartnett, and E.N.
Ganic),Chapter -. McGaw-Hill, New York.
Weaver, H.L. and Campbell, G.S. (+32/) : Use of peltiercoolers as soil heat ﬂux transducers.Soil Science
Society of America Journal, .3 : +*0/ῌ+*01.

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