Advertisement

Plant–water relations and the fibre saturation point

Authors

  • Sandra L. Berry,

    1. Ecosystem Dynamics Group, Research School of Biological Sciences, Institute of Advanced Studies, The Australian National University, Canberra ACT 0200, Australia
    Search for more papers by this author
  • Michael L. Roderick

    Corresponding author
    1. Ecosystem Dynamics Group, Research School of Biological Sciences, Institute of Advanced Studies, The Australian National University, Canberra ACT 0200, Australia
      Author for correspondence: Michael L. Roderick Tel: +61 2 61254020 Fax: +61 2 61255095 Email: Michael.Roderick@anu.edu.au
    Search for more papers by this author

Author for correspondence: Michael L. Roderick Tel: +61 2 61254020 Fax: +61 2 61255095 Email: Michael.Roderick@anu.edu.au

Abstract

Contents

  • Summary 1

  • I. Introduction 2
  • II. The FSP: an overview 2
  • III. Equilibrium thermodynamics and the FSP 5
  • IV. Inside the FSP 7
  • V.  Living trees and the FSP 10
  • VI.  Conclusions 11
  • Acknowledgements 12

  • References 12

Summary

This review is about the behaviour of water in cell walls. The aim is to introduce to biologists the concept of the fibre saturation point (FSP), and the related research of material scientists and engineers on the thermodynamics and chemistry of water in timber and wood. In the review, we first summarise what the FSP is, why it is important and how the FSP is routinely used by engineers and material scientists to estimate the volume fractions of solid, liquid and gas phases in bulk timber. We then show that the FSP can be intuitively understood using equilibrium thermodynamics. That analysis shows that the FSP is based on the concept that a certain (and repeatable) amount of water is chemically bound to cellulose and other substances in wood. That water, sometimes called bound water, exists in a water–cell wall mixture. The noted physical chemist and wood scientist, A. J. Stamm, called this mixture a ‘solid solution’. In timber, the ‘solid solution’ is considered a separate phase from adjacent water in either a pure liquid phase or a vapour phase. Following that, we examine the FSP and wood–water dynamics at the molecular and cellular level. Despite differences between timber and living trees, we conclude that the FSP-based framework long used by material scientists and engineers is likely to be useful to biologists.

Ancillary