UCL Discovery
UCL home » Library Services » Electronic resources » UCL Discovery

Persistent decay of fresh xylem hydraulic conductivity varies with pressure gradient and marks plant responses to injury

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. Green open access

[thumbnail of pce.13893.pdf]
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
Downloads since deposit
68Downloads
Download activity - last month
Download activity - last 12 months
Downloads by country - last 12 months

Archive Staff Only

View Item View Item