An analysis of the steady-state heat balance method for measuring sap flow in plants

J. M. Baker, J. L. Nieber

Research output: Contribution to journalArticlepeer-review

47 Scopus citations

Abstract

An axisymmetric finite element model of heat flow was used to evaluate some of the assumptions inherent in the steady-state heat balance method for measuring sap flow in herbaceous plants. Results indicate that the gauge slightly overestimates conduction up and down the stem when sap flow is nearly zero, causing a corresponding underestimate of the sheath conductance and the radial outward heat flux. As sap flow rates increase, the temperature distribution in the stem and gauge is altered to the point that the one-dimensional Fourier equations are no longer applicable and the individual heat fluxes in the system are poorly estimated. However, the errors are largely self-compensating, so that the resulting gauge estimate of the heat absorbed by the sap stream is reasonably accurate. The model indicates that stem vascular anatomy affects the accuracy of the method, predicting that, in general, the method should be more accurate with dicots than with monocots.

Original languageEnglish (US)
Pages (from-to)93-109
Number of pages17
JournalAgricultural and Forest Meteorology
Volume48
Issue number1-2
DOIs
StatePublished - Oct 1989

Fingerprint Dive into the research topics of 'An analysis of the steady-state heat balance method for measuring sap flow in plants'. Together they form a unique fingerprint.

Cite this