Determinants of tree species turnover in a southern Amazonian rain forest
Article first published online: 13 AUG 2012
© 2012 International Association for Vegetation Science
Journal of Vegetation Science
Volume 24, Issue 2, pages 284–295, March 2013
How to Cite
Guèze, M., Paneque-Gálvez, J., Luz, A. C., Pino, J., Orta-Martínez, M., Reyes-García, V., Macía, M. J. (2013), Determinants of tree species turnover in a southern Amazonian rain forest. Journal of Vegetation Science, 24: 284–295. doi: 10.1111/j.1654-1103.2012.01461.x
- Issue published online: 24 JAN 2013
- Article first published online: 13 AUG 2012
- Manuscript Accepted: 12 JUL 2012
- Manuscript Received: 4 MAR 2012
- FBBVA. Grant Number: BIOCON_06_106-07
- Dispersal limitation;
- Environmental variables;
- Geographical distances;
- Lowland Bolivia;
- Niche factors;
- Plant community assembly;
- Soil variables
What is the relative importance of environmental variables and geographical distances to explain tree species turnover? Are these patterns consistent for different tree categories, i.e. all trees (DBH ≥ 2.5 cm), large trees (DBH ≥ 10 cm), small trees sensu lato (DBH < 10 cm) and small trees sensu stricto (strictly understorey species, DBH < 10 cm)?
Department of Beni, Bolivia, southwestern Amazon.
A total of 55 0.1-ha plots were inventoried in old-growth terra firme forest in seven sites. Composite soil samples from each plot were analysed for physical and chemical properties. Environmental and geographical influences on tree species turnover were quantified with Mantel correlations and variation partitioning based on multiple regressions on distance matrices.
Floristic differences between sites yielded significant correlations with both geographical distances and environmental variables (pH, Ca, Mg, exchangeable acidity, C:N ratio, sand content) for all tree categories. Phosphorus was correlated with floristic patterns only for small trees sensu stricto. Together, geographical distances and environmental variables explained 62% of the floristic variation for all trees. Environmental variables explained more variation for large trees than for small trees sensu stricto.
The results support the hypothesis that species distributions are driven by both geographical distances (as quantifiers of dispersal processes) and environmental variables (niche factors) in similar proportions. Spatial floristic patterns of large trees and small trees sensu stricto were in general terms congruent.