Monday, August 3, 2009 - 4:20 PMOOS 4-9: The importance of wood traits and hydraulic conductance for the performance and life history strategies of 42 rainforest tree species
Lourens Poorter1, Imole McDonald1, Esther Fichtler2, Juan Carlos Licona3, Marielos Peņa-Claros3, Frank Sterck1, and Ute Sass-Klaassen1. (1) Wageningen University, (2) Institute of Agronomy in the Tropics, (3) Bolivian Forest Research Institute (IBIF)
Background/Question/Methods Stem wood density is emerging recently as a core plant functional trait, because of its importance for the stability, defense, architecture, hydraulics, carbon gain and growth potential of plants. Given this pivotal role of wood density for many aspects of plant performance, it is thought that wood density and associated wood anatomical traits may partly underlie the growth-survival trade-off that is frequently observed across woody plant species.
In this study we compare quantitative wood traits of 42 coexisting Bolivian rain forest tree species. We take advantage from dynamic data from large-scale permanent sample plots to calculate population-level growth and survival rates for trees between 10 and 50 cm diameter at breast height. We evaluate how wood anatomical traits are related to these vital rates, and to two important strategy axes; the shade tolerance and adult stature of the species.
Results/Conclusions Of all tissue fractions (fiber, parenchyma, vessels), only fiber cross-sectional area was significantly related to wood density, but surprisingly this was a negative rather than a positive relationship. Across species, the diameter growth rate increases with the water transport capacity (average vessel diameter, and hydraulic conductance), and decreases with the stem construction cost (wood density) of the species. Survival rate increases with the stem material strength (wood density) of the species, but was not related to the fraction of fibers in the wood. Both light-demanding species and tall species have wood traits that are associated with fast growth (large vessel diameter, high hydraulic conductance, and low wood density). In sum, wood traits vary substantially across co-occurring tree species, with large consequences for plant performance. Wood traits are for that reason also closely related to the life history strategies of the species.
In this study we compare quantitative wood traits of 42 coexisting Bolivian rain forest tree species. We take advantage from dynamic data from large-scale permanent sample plots to calculate population-level growth and survival rates for trees between 10 and 50 cm diameter at breast height. We evaluate how wood anatomical traits are related to these vital rates, and to two important strategy axes; the shade tolerance and adult stature of the species.
Results/Conclusions Of all tissue fractions (fiber, parenchyma, vessels), only fiber cross-sectional area was significantly related to wood density, but surprisingly this was a negative rather than a positive relationship. Across species, the diameter growth rate increases with the water transport capacity (average vessel diameter, and hydraulic conductance), and decreases with the stem construction cost (wood density) of the species. Survival rate increases with the stem material strength (wood density) of the species, but was not related to the fraction of fibers in the wood. Both light-demanding species and tall species have wood traits that are associated with fast growth (large vessel diameter, high hydraulic conductance, and low wood density). In sum, wood traits vary substantially across co-occurring tree species, with large consequences for plant performance. Wood traits are for that reason also closely related to the life history strategies of the species.