Weak tradeoff between xylem safety and xylem-specific hydraulic efficiency across the world's woody plant species
Sean M. Gleason
(1, 2)
,
Mark Westoby
(1)
,
Steven Jansen
(3)
,
Brendan Choat
(4)
,
Uwe G. Hacke
(5)
,
Robert B. Pratt
(6)
,
Radika Bhaskar
(7)
,
Tim J. Brodribb
(8)
,
Sandra J. Bucci
(9)
,
Kung-Fang Cao
(10)
,
Hervé H. Cochard
(11)
,
Sylvain S. Delzon
(12)
,
Jean-Christophe Domec
(13)
,
Ze-Xin Fan
(14)
,
Taylor S. Feild
(15)
,
Anna L. Jacobsen
(6)
,
Daniel M. Johnson
(16)
,
Frederic Lens
(17)
,
Hafiz Maherali
(18)
,
Jordi Martinez-Vivalta
(19, 20)
,
Stefan Mayr
(21)
,
Katherine A. Mcculloh
(22)
,
Maurizio Mencuccini
(23, 20)
,
Patrick J. Mitchell
(24)
,
Hugh Morris
(3)
,
Andrea Nardini
(25)
,
Jarmila Pittermann
(26)
,
Lenka Plavcová
(3, 5)
,
Stefan G. Schreiber
(5)
,
John S. Sperry
(27)
,
Ian J. Wright
(1)
,
Amy E. Zanne
(28)
1
Department of Biological Sciences
2 USDA - United States Department of Agriculture
3 Institute of Systematic Botany and Ecology
4 Hawkesbury Institute for the Environment
5 Department of Renewable Resources
6 California State University
7 Haverford College
8 School of Biological Sciences [Hobart]
9 UNPSJB - Universidad Nacional de la Patagonia San Juan Bosco
10 Department of Physics - Guangxi University
11 PIAF - Laboratoire de Physique et Physiologie Intégratives de l'Arbre Fruitier et Forestier
12 BioGeCo - Biodiversité, Gènes & Communautés
13 UMR ISPA - Interactions Sol Plante Atmosphère
14 Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden
15 School of Marine and Tropical Biology
16 Department of Forest, Rangeland and Fire Sciences
17 Naturalis Biodiversity Center [Leiden]
18 University of Guelph - Department of Integrative Biology
19 CREAF - Centre for Ecological Research and Forestry Applications
20 ICREA - Institució Catalana de Recerca i Estudis Avançats = Catalan Institution for Research and Advanced Studies
21 Department of Botany
22 Department of Botany
23 School of GeoSciences
24 CSIRO - Commonwealth Scientific and Industrial Research Organisation [Canberra]
25 Università degli studi di Trieste = University of Trieste
26 University of California Santa Cruz - Department of Ecology and Evolutionary Biology
27 Department of Biology
28 SUNY - State University of New York
2 USDA - United States Department of Agriculture
3 Institute of Systematic Botany and Ecology
4 Hawkesbury Institute for the Environment
5 Department of Renewable Resources
6 California State University
7 Haverford College
8 School of Biological Sciences [Hobart]
9 UNPSJB - Universidad Nacional de la Patagonia San Juan Bosco
10 Department of Physics - Guangxi University
11 PIAF - Laboratoire de Physique et Physiologie Intégratives de l'Arbre Fruitier et Forestier
12 BioGeCo - Biodiversité, Gènes & Communautés
13 UMR ISPA - Interactions Sol Plante Atmosphère
14 Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden
15 School of Marine and Tropical Biology
16 Department of Forest, Rangeland and Fire Sciences
17 Naturalis Biodiversity Center [Leiden]
18 University of Guelph - Department of Integrative Biology
19 CREAF - Centre for Ecological Research and Forestry Applications
20 ICREA - Institució Catalana de Recerca i Estudis Avançats = Catalan Institution for Research and Advanced Studies
21 Department of Botany
22 Department of Botany
23 School of GeoSciences
24 CSIRO - Commonwealth Scientific and Industrial Research Organisation [Canberra]
25 Università degli studi di Trieste = University of Trieste
26 University of California Santa Cruz - Department of Ecology and Evolutionary Biology
27 Department of Biology
28 SUNY - State University of New York
Mark Westoby
- Fonction : Auteur
- PersonId : 765099
- ORCID : 0000-0001-7690-4530
Steven Jansen
- Fonction : Auteur
- PersonId : 765107
- ORCID : 0000-0002-4476-5334
Hervé H. Cochard
- Fonction : Auteur
- PersonId : 739
- IdHAL : herve-cochard
Maurizio Mencuccini
- Fonction : Auteur
- PersonId : 769841
- ORCID : 0000-0003-0840-1477
Andrea Nardini
- Fonction : Auteur
- PersonId : 769794
- ORCID : 0000-0002-5208-0087
Résumé
The evolution of lignified xylem allowed for the efficient transport of water under tension, but also exposed the vascular network to the risk of gas emboli and the spread of gas between xylem conduits, thus impeding sap transport to the leaves. A well-known hypothesis proposes that the safety of xylem (its ability to resist embolism formation and spread) should trade off against xylem efficiency (its capacity to transport water). We tested this safety–efficiency hypothesis in branch xylem across 335 angiosperm and 89 gymnosperm species. Safety was considered at three levels: the xylem water potentials where 12%, 50% and 88% of maximal conductivity are lost. Although correlations between safety and efficiency were weak (r2 < 0.086), no species had high efficiency and high safety, supporting the idea for a safety–efficiency tradeoff. However, many species had low efficiency and low safety. Species with low efficiency and low safety were weakly associated (r2 < 0.02 in most cases) with higher wood density, lower leaf- to sapwood-area and shorter stature. There appears to be no persuasive explanation for the considerable number of species with both low efficiency and low safety. These species represent a real challenge for understanding the evolution of xylem.