Bonetti, S;
Breitenstein, D;
Fatichi, S;
Domec, J-C;
Or, D;
(2021)
Persistent decay of fresh xylem hydraulic conductivity varies with pressure gradient and marks plant responses to injury.
Plant, Cell and Environment
, 44
(2)
pp. 371-386.
10.1111/pce.13893.
Preview |
Text
pce.13893.pdf - Accepted Version Download (1MB) | Preview |
Abstract
Defining plant hydraulic traits is central to the quantification of ecohydrological processes ranging from land-atmosphere interactions, to tree mortality, and water-carbon budgets. A key plant trait is the xylem specific hydraulic conductivity (Kx ), that describes the plant's vascular system capacity to transport water. While xylem's vessels and tracheids are dead upon maturity, the xylem is neither inert nor deadwood, various components of the sapwood and surrounding tissue remaining alive and functional. Moreover, the established definition of Kx assumes linear relations between water flux and pressure gradient by tacitly considering the xylem as a "passive conduit". Here we reexamine this notion of an inert xylem by systematically characterizing xylem flow in several woody plants using Kx measurements under constant and cyclic pressure gradients. Results show a temporal and pressure gradient dependence of Kx . Additionally, microscopic features in "living branches" are irreversibly modified upon drying of the xylem thus differentiating the macroscopic definition of Kx for living and dead xylem. The findings highlight the picture of the xylem as a complex and delicate conductive system whose hydraulic behavior transcends a passive gradient-based flow. The study sheds new light on xylem conceptualization, conductivity measurement protocols, in situ long-distance water transport, and ecosystem modeling. This article is protected by copyright. All rights reserved.
Type: | Article |
---|---|
Title: | Persistent decay of fresh xylem hydraulic conductivity varies with pressure gradient and marks plant responses to injury |
Location: | United States |
Open access status: | An open access version is available from UCL Discovery |
DOI: | 10.1111/pce.13893 |
Publisher version: | http://dx.doi.org/10.1111/pce.13893 |
Language: | English |
Additional information: | This version is the author accepted manuscript. For information on re-use, please refer to the publisher’s terms and conditions. |
Keywords: | Plant hydraulic traits, Plant vascular system, Sapflow, Xylem conductivity measurements, Xylem hydraulic conductivity |
UCL classification: | UCL UCL > Provost and Vice Provost Offices > UCL BEAMS UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of the Built Environment UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of the Built Environment > Bartlett School Env, Energy and Resources |
URI: | https://discovery.ucl.ac.uk/id/eprint/10111453 |
Archive Staff Only
View Item |