Xylem plasticity allows rapid hydraulic adjustment to annual climatic variability
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Thanks to acclimation, trees overcome environmental changes and endure for centuries. The anatomy of water conducting cells is an important factor determining plant success. Forming cells are coupled with the environment and their properties are naturally archived in the wood. Its variability across tree rings can thus provide a retrospective of plant’s hydraulic adjustments. In this work, we measured lumen and wall thickness of tracheids along tree-rings to explore how trees regulate their conducting system under variable plant-water conditions. Tracheids were measured along 51 dated rings of five mature Larix decidua and Picea abies trees from a low elevation site. Anatomical-based chronologies of annual growth performance, hydraulic conductance and safety, and construction costs were built. Similarities among chronologies and the relation to monthly climate data were analyzed. Most parameters displayed high annual plasticity which was partly coherent among trees and mostly associated with radial growth. In general, summer drought reduced growth and potential hydraulic conductivity of the forming ring, and increased hydraulic safety and construction costs. To evaluate the functional relevance of the annual acclimation, the conductivity of the forming ring relative to the entire sapwood needs to be assessed.
KeywordsTree-ring anatomy Tracheid-cell chronologies Plant-water relations Larix decidua Picea abies
This study was supported by Swiss National Foundation through an International short visit (Grant number: #131408) and through the cooperation on the project INTEGRAL (#121859). We would like to thank David Frank and Georg von Arx for their assistance and critical discussion of an earlier version of the manuscript, and Kathlene English and Gregory King for the English review.
- Barnard DM, Meinzer FC, Lachenbruch B, McCulloh KA, Johnson DM, Woodruff DR (2011) Climate-related trends in sapwood biophysical properties in two conifers: avoidance of hydraulic dysfunction through coordinated adjustments in xylem efficiency, safety and capacitance. Plant Cell Environ 34:643–654PubMedCrossRefGoogle Scholar
- Cook ER, Kairiukstis LA (1990) Methods of dendrochronology applications in the environmental sciences. Kluwer, DordrechtGoogle Scholar
- Fritts HC (1976) Tree rings and climate. Academic Press, LondonGoogle Scholar
- Holbrook NM, Zwieniecki MA (2005) Vascular transport in plants. Elsevier, AmsterdamGoogle Scholar