Field measurements of xylem cavitation: Are acoustic emissions useful?
Field measurements of xylem cavitation: Are acoustic emissions useful?
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DOI：
10.1093/jxb/47.11.1643
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发表时间：
1996-11-01
影响因子：
6.9
通讯作者：
Grace, J
中科院分区：
文献类型：
--
作者：
Jackson, GE;Grace, J
木质部内水柱的空化对植物的水关系有害，因为它会导致栓塞，从而降低水力传导性。这种空化现象可以被检测到，因为它伴随着声发射的产生，可以通过超声波检测到声发射，并在几天内自动记录。声发射技术可用于确定对工厂导水系统造成损害的阈值水势。它可以揭示哪些环境变量对植物的水关系有害，以及植物的哪些部分对空化最敏感。可以进行物种比较，以及同一物种在不同环境下的比较，以获得耐旱性的指标。然而，声发射在确定传导茎中栓塞的比例方面用途有限，并且需要其他方法来确定导水率的降低百分比。
Cavitation of water columns within the xylem is deleterious for plant water relations as it results in embolism, so reducing hydraulic conductivity. This cavitation can be detected as it is accompanied by the production of acoustic emissions, which can be detected ultrasonically and logged automatically over periods of days, The acoustic emission technique is useful to determine the threshold water potential at which damage to the water-conducting system of the plant is initiated. It can reveal which environmental variables are deleterious to the plant water relations, and which parts of the plant are most sensitive to cavitation. Species comparisons, and comparisons of the same species in different environments can be made, to obtain indications of drought tolerance. However, acoustic emissions have only a limited use in determining the proportion of embolism in a conducting stem, and other methods are needed to find the percentage reduction in hydraulic conductivity.