Growth responses of 15 rain-forest tree species to a light gradient: the relative importance of morphological and physiological traits
Article first published online: 27 MAR 2002
1999 British Ecological Society
Volume 13, Issue 3, pages 396–410, June 1999
How to Cite
Poorter, L. (1999), Growth responses of 15 rain-forest tree species to a light gradient: the relative importance of morphological and physiological traits. Functional Ecology, 13: 396–410. doi: 10.1046/j.1365-2435.1999.00332.x
- Issue published online: 27 MAR 2002
- Article first published online: 27 MAR 2002
- growth analysis;
- shade tolerance;
- tropical rain forest
1. Growth of seedlings of 15 rain-forest tree species was compared under controlled conditions, at six different light levels (3, 6, 12, 25, 50 and 100% daylight).
2. Most plant variables showed strong ontogenetic changes; they were highly dependent on the biomass of the plant.
3. Growth rate was highest at intermediate light levels (25–50%) above which it declined. Most plant variables showed a curvilinear response to irradiance, with the largest changes at the lowest light levels.
4. There was a consistent ranking in growth between species; species that were fast growing in a low-light environment were also fast growing in a high-light environment.
5. At low light, interspecific variation in relative growth rate was determined mainly by differences in a morphological trait, the leaf area ratio (LAR), whereas at high light it was determined mainly by differences in a physiological trait, the net assimilation rate (NAR).
6. NAR became a stronger determinant of growth than LAR in more than 10–15% daylight. As light availability in the forest is generally much lower than this threshold level, it follows that interspecific variation in growth in a forest environment is mainly owing to variation in morphology.