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Correction of Systematic Errors in Estimates of Transpiration Obtained Using a Constant Temperature Heat Balance Technique

Published online by Cambridge University Press:  03 October 2008

Ahmed A. H. Khan  and
Chin K. Ong
Ahmed A. H. Khan
Affiliation:
International Centre for Research in Agroforestry (ICRAF), PO Box 30677, Nairobi, Kenya
Chin K. Ong
Affiliation:
International Centre for Research in Agroforestry (ICRAF), PO Box 30677, Nairobi, Kenya
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Summary

Field measurements using 30-month-old grevillea trees indicated that the three main sources of error in sap flow estimation can be overcome by: estimating the temperature bias with the gauge heater switched off or covering the whole trunk with 20 mm thick styrofoam sheet and alumimium foil; or by inserting thermocouples in the stem and accounting for radial and conductive heat losses. These corrections reduce gauge error for tree trunks (50–90 mm diameter) from 10–47% to ±7%. In the absence of a large lysimeter, a comparison of sap flow rates was made by attaching gauges to the trunk and a single terminal branch on the same tree.

Calibrado del flujo de la savia en los árboles del género Grevillea

Type
Research Article
Information
Experimental Agriculture , Volume 31 , Issue 4 , October 1995 , pp. 461 - 472
Copyright
Copyright © Cambridge University Press 1995

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References

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