Summary
Leaf diffusion resistances may lower the values of leaf water potentials found byin situ measurements with silver-foil psychrometers. With the instrumentation used, the bias ranges from zero to increasing negative deviations as leaf diffusion resistances become larger than 3.5 cm-1 sec.
Water potentials determined with the dewpoint technique are unaffected by diffusion resistances.In situ measurements by this method may also be carried out with the silver-foil sensor.
Hence, one and the same sensor may serve to trace both leaf water potentials and leaf diffusion resistance through dewpoint and psychrometric measurements. re]19760720
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Zanstra, P.E., Hagenzieker, F. Comments on the psychrometric determination of leaf water potentialsin situ . Plant Soil 48, 347–367 (1977). https://doi.org/10.1007/BF02187246
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DOI: https://doi.org/10.1007/BF02187246