© 1997 Heron Publishing—Victoria, Canada
Biomechanical and hydraulic determinants of tree structure in Scots pine: anatomical characteristics
Maurizio Mencuccini (1, 4), John Grace (2) and Marco Fioravanti (3)
1. Istituto di Ecologia e Selvicoltura, Universita' di Firenze, Via S. Bonaventura, 13, 50145 Firenze, Italy / 2. Institute of Ecology and Resource Management, University of Edinburgh, The King's Buildings, Darwin Building, Mayfield Road,
EH9 3JU Edinburgh, U.K. / 3. Istituto de Assestamento Forestale e Tecnologia del Legno, Universita' di Firenze, Via S. Bonaventura, 13, 50145 Firenze,
Italy / 4. Boyce Thompson Institute for Plant Research at Cornell University, Tower Road, Ithaca, NY 14850, USA / Received November 22, 1995
Summary
The development of anatomical, hydraulic and biomechanical properties in Scots pine (Pinus sylvestris L.) stems aged 7 to 59 years was followed. The hydraulic diameter and length of tracheids increased with age to a maximum
at 15 and 35 years, respectively. Number of tracheids per unit of sapwood area decreased with age to a minimum of 500–600
tracheids mm–2. Variations in specific hydraulic conductivity and Young’s modulus of stems were associated with variation in anatomical
properties.
Over the time sequence considered, hydraulic and mechanical properties were positively related to each other and followed
a similar developmental pattern, with no suggestion of a trade-off between the two. For most of the tree’s life-cycle, heartwood
made only a small contribution to whole-section mechanical stiffness because of its location close to the flexural neutral
axis, and because of the presence of juvenile wood.
Keywords:
heartwood, Pinus sylvestris, sapwood, xylem anatomy, xylem conductivity, Young's modulus.
