A Cold Temperature Error in the Pressure Chamber Technique
Keyword(s):
Pressure chamber data for Engelmann spruce indicate that a cold temperature error causes artificially low (more negative) xylem pressure potential (Ψxp) values below −0.5 °C xylem temperature. Heat of compression in the chamber causes partial thawing of the frozen sample allowing some water to be forced from the twig at a reasonable, although artificially low, Ψxp value. It is important that the investigator know sample temperature in order not to misinterpret these low Ψxp values as indicative of severe water stress due to decreased absorption of water by root systems at low soil temperatures.
1979 ◽
Vol 9
(3)
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pp. 297-304
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1977 ◽
Vol 13
(4)
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pp. 341-351
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Keyword(s):
1990 ◽
Vol 20
(9)
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pp. 1508-1513
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Keyword(s):
1985 ◽
Vol 15
(5)
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pp. 818-821
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