Ultrasonic acoustic emissions in drought-stressed trees - more than signals from cavitation?
Data(s) |
01/09/2008
|
---|---|
Identificador |
http://boris.unibe.ch/30439/1/NewPhytol_179_1070.pdf Zweifel, Roman; Zeugin, Fabienne (2008). Ultrasonic acoustic emissions in drought-stressed trees - more than signals from cavitation? New Phytologist, 179(4), pp. 1070-1079. Oxford: Wiley-Blackwell 10.1111/j.1469-8137.2008.02521.x <http://dx.doi.org/10.1111/j.1469-8137.2008.02521.x> doi:10.7892/boris.30439 info:doi:10.1111/j.1469-8137.2008.02521.x urn:issn:0028-646X |
Idioma(s) |
eng |
Publicador |
Wiley-Blackwell |
Relação |
http://boris.unibe.ch/30439/ |
Direitos |
info:eu-repo/semantics/restrictedAccess |
Fonte |
Zweifel, Roman; Zeugin, Fabienne (2008). Ultrasonic acoustic emissions in drought-stressed trees - more than signals from cavitation? New Phytologist, 179(4), pp. 1070-1079. Oxford: Wiley-Blackwell 10.1111/j.1469-8137.2008.02521.x <http://dx.doi.org/10.1111/j.1469-8137.2008.02521.x> |
Tipo |
info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion PeerReviewed |
Resumo |
Ultrasonic acoustic emission (UAE) in trees is often related to collapsing water columns in the flow path as a result of tensions that are too strong (cavitation). However, in a decibel (dB) range below that associated with cavitation, a close relationship was found between UAE intensities and stem radius changes. • UAE was continuously recorded on the stems of mature field-grown trees of Scots pine (Pinus sylvestris) and pubescent oak (Quercus pubescens) at a dry inner-Alpine site in Switzerland over two seasons. The averaged 20-Hz records were related to microclimatic conditions in air and soil, sap-flow rates and stem-radius fluctuations de-trended for growth (ΔW). • Within a low-dB range (27 ± 1 dB), UAE regularly increased and decreased in a diurnal rhythm in parallel with ΔW on cloudy days and at night. These low-dB emissions were interrupted by UAE abruptly switching between the low-dB range and a high-dB range (36 ± 1 dB) on clear, sunny days, corresponding to the widely supported interpretation of UAE as sound from cavitations. • It is hypothesized that the low-dB signals in drought-stressed trees are caused by respiration and/or cambial growth as these physiological activities are tissue water-content dependent and have been shown to produce courses of CO2 efflux similar to our courses of ΔW and low-dB UAE. |
Formato |
application/pdf |
Palavras-Chave | #570 Life sciences; biology |