Đang chuẩn bị nút TẢI XUỐNG, xin hãy chờ
Tải xuống
Whereas the mechanical performance of plant organs has often been discussed in evolutionary biology [1,2], tree biomechanics has rarely been considered in the context of functional ecology. Functional ecology aims at understanding the functions of organisms that result in fluxes of biomass or energy within an ecosystem, e.g., a forest. This discipline studies the processes controlling these fluxes, at either the scale of an individual, community, or ecosystem, with their response to natural or anthropic environmental variations | 1 Tree Biomechanics and Growth Strategies in the Context of Forest Functional Ecology Meriem Fournier Alexia Stokes Catherine Coutand Thierry Fourcaud and Bruno Moulia CONTENTS 1.1 Introduction.2 1.2 Some Biomechanical Characteristics of Trees.3 1.2.1 Wood as a Lightweight Cellular- and Fiber-Reinforced Material 3 1.2.2 Wood Variability.5 1.2.3 Mechanics of Secondary Growth.6 1.3 Biomechanical and Ecological Significance of Height.6 1.3.1 Biomechanical Environmental Constraints on Tree Height and Their Ecological Significance.7 1.3.1.1 Safety Factor.7 1.3.1.2 Analysis of Successive Shapes Occurring during Growth Due to the Continuous Increase of Supported Loads.8 1.3.2 Biomechanical Functional Traits Defined from Risk Assessment.9 1.3.2.1 Buckling or Breakage of Stems.9 1.3.2.2 Root Anchorage.9 1.3.3 Biomechanical Functional Traits and Processes Involved in Height Growth Strategy.13 1.4 The Growth Processes That Control the Mechanical Stability of Slender Tree Stems. 14 1.4.1 The Mechanical Control of Growth.14 1.4.2 The Control of Stem Orientation to Maintain or Restore the Tree Form and Allow Vertical Growth.16 1.4.3 The Control of Root Growth to Secure Anchorage.21 1.5 A Practical Application of Tree Biomechanics in Ecology.21 1.6 Conclusion.24 References.25 1 Copyright 2006 Taylor Francis Group LLC 2 Ecology and Biomechanics 1.1 INTRODUCTION Whereas the mechanical performance of plant organs has often been discussed in evolutionary biology 1 2 tree biomechanics has rarely been considered in the context of functional ecology. Functional ecology aims at understanding the functions of organisms that result in fluxes of biomass or energy within an ecosystem e.g. a forest. This discipline studies the processes controlling these fluxes at either the scale of an individual community or ecosystem with their response to natural or anthropic environmental variations. Ecological differences among vascular land plant species arise from different ways of acquiring the same
