The Widened Pipe Model of plant hydraulic evolution

Autor: Jayanth R. Banavar, Julieta A. Rosell, Amos Maritan, Todd E. Dawson, Kuo-Fang Chung, Rodrigo P. Rocha, Tommaso Anfodillo, Franco Cardin, Silvia Lechthaler, Alex Fajardo, Emilio Petrone‐Mendoza, Samir Suweis, Carmen Regina Marcati, Alberto Lovison, Mark E. Olson, Loren Koçillari, Cecilia Martínez-Pérez, Alí Segovia-Rivas, Alberto Echeverría, Andrea Rinaldo, Cameron B. Williams
Přispěvatelé: Univ Padua, Ist Italiano Tecnol, Univ Nacl Autonoma Mexico, Universidade Federal de Santa Catarina (UFSC), Univ Calif Berkeley, Univ Talca, Universidade Estadual Paulista (Unesp), Acad Sinica, Channel Isl Natl Pk, Santa Barbara Bot Garden, No Arizona Univ, Ecole Polytechinque Fed Lausanne, Univ Oregon
Jazyk: angličtina
Rok vydání: 2021
Předmět:
Zdroj: Proceedings of the National Academy of Sciences of the United States of America, vol 118, iss 22
Web of Science
Repositório Institucional da UNESP
Universidade Estadual Paulista (UNESP)
instacron:UNESP
Proceedings of the National Academy of Sciences of the United States of America
Popis: Significance For most of its path through plant bodies, water moves in conduits in the wood. Plant water conduction is crucial for Earth’s biogeochemical cycles, making it important to understand how natural selection shapes conduit diameters along the entire lengths of plant stems. Can mathematical modeling and global sampling explain how wood conduits ought to widen from the tip of a plant to its trunk base? This question is evolutionarily important because xylem conduits should widen in a way that keeps water supply constant to the leaves as a plant grows taller. Moreover, selection should act on economy of construction costs of the conducting system. This issue is ecologically important because it helps suggest why climate change alters vegetation height worldwide.
Shaping global water and carbon cycles, plants lift water from roots to leaves through xylem conduits. The importance of xylem water conduction makes it crucial to understand how natural selection deploys conduit diameters within and across plants. Wider conduits transport more water but are likely more vulnerable to conduction-blocking gas embolisms and cost more for a plant to build, a tension necessarily shaping xylem conduit diameters along plant stems. We build on this expectation to present the Widened Pipe Model (WPM) of plant hydraulic evolution, testing it against a global dataset. The WPM predicts that xylem conduits should be narrowest at the stem tips, widening quickly before plateauing toward the stem base. This universal profile emerges from Pareto modeling of a trade-off between just two competing vectors of natural selection: one favoring rapid widening of conduits tip to base, minimizing hydraulic resistance, and another favoring slow widening of conduits, minimizing carbon cost and embolism risk. Our data spanning terrestrial plant orders, life forms, habitats, and sizes conform closely to WPM predictions. The WPM highlights carbon economy as a powerful vector of natural selection shaping plant function. It further implies that factors that cause resistance in plant conductive systems, such as conduit pit membrane resistance, should scale in exact harmony with tip-to-base conduit widening. Furthermore, the WPM implies that alterations in the environments of individual plants should lead to changes in plant height, for example, shedding terminal branches and resprouting at lower height under drier climates, thus achieving narrower and potentially more embolism-resistant conduits.
Databáze: OpenAIRE
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