Journal Article

Transpiration sensitivity of urban trees in a semi-arid climate is constrained by xylem vulnerability to cavitation

Elizaveta Litvak, Heather R. McCarthy and Diane E. Pataki

Edited by Guillermo Goldstein

in Tree Physiology

Volume 32, issue 4, pages 373-388
Published in print April 2012 | ISSN: 0829-318X
Published online March 2012 | e-ISSN: 1758-4469 | DOI: http://dx.doi.org/10.1093/treephys/tps015
Transpiration sensitivity of urban trees in a semi-arid climate is constrained by xylem vulnerability to cavitation

Show Summary Details

Preview

Establishing quantitative links between plant hydraulic properties and the response of transpiration to environmental factors such as atmospheric vapor pressure deficit (D) is essential for improving our ability to understand plant water relations across a wide range of species and environmental conditions. We studied stomatal responses to D in irrigated trees in the urban landscape of Los Angeles, California. We found a strong linear relationship between the sensitivity of tree-level transpiration estimated from sap flux (mT; slope of the relationship between tree transpiration and ln D) and transpiration at D = 1 kPa (ETref) that was similar to previous surveys of stomatal behavior in natural environments. In addition, mT was significantly related to vulnerability to cavitation of branches (P50). While mT did not appear to differ between ring- and diffuse-porous species, the relationship between mT and P50 was distinct by wood anatomy. Therefore, our study confirms systematic differences in water relations in ring- versus diffuse-porous species, but these differences appear to be more strongly related to the relationship between stomatal sensitivity to D and vulnerability to cavitation rather than to stomatal sensitivity per se.

Keywords: stomatal control; xylem embolism

Journal Article.  9380 words.  Illustrated.

Subjects: Plant Sciences and Forestry

Full text: subscription required

How to subscribe Recommend to my Librarian

Users without a subscription are not able to see the full content. Please, subscribe or login to access all content.