S. Pallardy, and
4th Int. Workshop on Functional-Structural Plant Models,
The model LIGNUM is a functional-structural tree model, which simulates annual development of
tree biomass and structure based on carbon balance (Perttunen et al., 1996; 1998; 2001). LIGNUM
represents the tree architecture with simple structural units called tree segment, branching point and
bud. The metabolic processes of the tree are associated directly to these elementary model building
blocks. The model calculates the shading relationships between tree compartments within the 3D
structure, and computes the annual interception of solar irradiance in each compartment. Intercepted
irradiance is used for estimating leaf photosynthesis, and net primary production (NPP) is obtained by
deducting the respiration losses in each tree compartment from the whole tree photosynthesis. Carbon
allocation within the tree is estimated following the pipe model principles (Shinozaki et al., 1964), i.e.
according to the relationships between the growth of foliage and water conducting and supporting
organs - branches and stem - needed to support it. Tree structure is updated according to the carbon
In this paper, we report application of LIGNUM model for simulating the growth and yield of
eastern cottonwood (Populus deltoides Bart. ex. Marsh.) in a dense short-rotation plantation and a
wide-spaced agroforestry system. In the cottonwood application of LIGNUM, there are also several
new modelling developments including use of real weather data and a biochemically derived
photosynthesis model (Le Roux et al., 1999; von Caemmerer and Farquhar, 1981). We also apply
different time steps for physiological processes and structure update (Sievanen et al., this volume),
and voxel space for estimating the interception of photon flux (Perttunen et al., this volume).
author = "M. Lu and P. Nygren and J. Perttunen and S. Pallardy and K. Palaniappan",
title = "Growth simulation of eastern cottonwood (Populus deltoids) using LIGNUM model incorporating real weather data",
year = 2004,
booktitle = "4th Int. Workshop on Functional-Structural Plant Models",
keywords = "data mining, visualization, plants",
url = "http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.125.6245&rep=rep1&type=pdf"
M. Lu, P. Nygren, J. Perttunen, S. Pallardy, and K. Palaniappan. Growth simulation of eastern cottonwood (Populus deltoids) using LIGNUM model incorporating real weather data. 4th Int. Workshop on Functional-Structural Plant Models, 2004.