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Biogeosciences, 6, 297-307, 2009
www.biogeosciences.net/6/297/2009/ doi:10.5194/bg-6-297-2009 © Author(s) 2009. This work is distributed under the Creative Commons Attribution 3.0 License. |
Do species traits determine patterns of wood production in Amazonian forests?
1Earth and Biosphere Institute, School of Geography, University of Leeds, Leeds, UK
2Smithsonian Tropical Research Institute, Balboa, Panama
3Center for Tropical Conservation, Duke University, Durham, USA
4Museu Paraense Emilio Goeldi, Belém, Brazil
5Museo Noel Kempff Mercado, Santa Cruz, Bolivia
6Department of Anthropology, New York University, NY, USA
7Smithsonian Institution, Washington DC, USA
8Instituto Nacional de Pesquisas da Amazônia, Manaus, Brazil
9Center for Applied Biodiversity Science, Conservation International, Washington DC, USA
10Biological Dynamics of Forest Fragments Project, Manaus, Brazil
11Proyecto Flora del Perú, Jardin Botanico de Missouri, Oxapampa, Perú
12Missouri Botanical Garden, c/o Naturaleza y Cultura Internacional, Loja, Ecuador
13Center for International Forestry Research, Tapajos, Brazil
14EMBRAPA Amazonia Oriental, Belém, Brazil
15Oxford University Centre for the Environment, Oxford, UK
Abstract. Understanding the relationships between plant traits and ecosystem properties at large spatial scales is important for predicting how compositional change will affect carbon cycling in tropical forests. In this study, we examine the relationships between species wood density, maximum height and above-ground, coarse wood production of trees ≥10 cm diameter (CWP) for 60 Amazonian forest plots. Average species maximum height and wood density are lower in Western than Eastern Amazonia and are negatively correlated with CWP. To test the hypothesis that variation in these traits causes the variation in CWP, we generate plot-level estimates of CWP by resampling the full distribution of tree biomass growth rates whilst maintaining the appropriate tree-diameter and functional-trait distributions for each plot. These estimates are then compared with the observed values. Overall, the estimates do not predict the observed, regional-scale pattern of CWP, suggesting that the variation in community-level trait values does not determine variation in coarse wood productivity in Amazonian forests. Instead, the regional gradient in CWP is caused by higher biomass growth rates across all tree types in Western Amazonia. Therefore, the regional gradient in CWP is driven primarily by environmental factors, rather than the particular functional composition of each stand. These results contrast with previous findings for forest biomass, where variation in wood density, associated with variation in species composition, is an important driver of regional-scale patterns in above-ground biomass. Therefore, in tropical forests, above-ground wood productivity may be less sensitive than biomass to compositional change that alters community-level averages of these plant traits.
Citation: Baker, T. R., Phillips, O. L., Laurance, W. F., Pitman, N. C. A., Almeida, S., Arroyo, L., DiFiore, A., Erwin, T., Higuchi, N., Killeen, T. J., Laurance, S. G., Nascimento, H., Monteagudo, A., Neill, D. A., Silva, J. N. M., Malhi, Y., López Gonzalez, G., Peacock, J., Quesada, C. A., Lewis, S. L., and Lloyd, J.: Do species traits determine patterns of wood production in Amazonian forests?, Biogeosciences, 6, 297-307, doi:10.5194/bg-6-297-2009, 2009.