Co-ordinating Editor: Otto Wildi
Pollen–vegetation relationships along steep climatic gradients in western Amazonia
Version of Record online: 19 APR 2011
© 2011 International Association for Vegetation Science
Journal of Vegetation Science
Volume 22, Issue 5, pages 795–806, October 2011
How to Cite
Urrego, D. H., Silman, M. R., Correa-Metrio, A. and Bush, M. B. (2011), Pollen–vegetation relationships along steep climatic gradients in western Amazonia. Journal of Vegetation Science, 22: 795–806. doi: 10.1111/j.1654-1103.2011.01289.x
Urrego, D.H. (corresponding author, firstname.lastname@example.org); Correa-Metrio, A. (email@example.com) & Bush, M.B. (firstname.lastname@example.org): Department of Biological Sciences, Florida Institute of Technology, 150 West University Boulevard, Melbourne FL 32901, USA Silman, M.R. (email@example.com): Department of Biology, Wake Forest University, 1834 Wake Forest Rd., Winston-Salem NC 27106, USA.
- Issue online: 1 SEP 2011
- Version of Record online: 19 APR 2011
- Received 10 October 2010, Accepted 16 February 2011
- Bioclimatic envelopes;
- Moss polsters;
- Pollen calibration;
- Probability density functions;
- Vegetation plot data
Question: How accurately do Amazonian montane forest pollen spectra reflect the vegetation? Can compositional changes observed in the vegetation along environmental gradients be identified in the pollen spectra? How well do herbarium collection data and bioclimatic envelopes represent abundance changes along elevation gradients?
Location: Amazonian montane forests, Peru.
Methods: Moss polsters collected along five altitudinal transects spanning over 3000 m a.s.l. were used to characterize pollen spectra. Vegetation plot data from a network of 15 1-ha permanent plots were used to correlate pollen spectra with present-day vegetation. Probability density functions (PDFs) fitted to pollen and plot data allowed comparisons using Spearman correlation coefficients. Ordination analyses were used to summarize changes in pollen spectra. Correlations between pollen-based PDFs and previously-published herbarium collection PDFs were also evaluated.
Results: Pollen spectra closely reflected changes in species composition along elevation gradients. A mid-elevation shift in pollen spectra was identified using ordination analyses. Pollen spectra from the driest forest in our data set were statistically different from those of wet forests. Pollen abundance PDFs along the altitudinal gradient were significantly correlated (P<0.01) with PDFs fitted to plot abundance, basal area and herbarium collection data for ten out of 11 taxa analysed.
Conclusions: Pollen spectra closely reflected the vegetation composition of Amazonian montane forests. The differentiation of pollen spectra from dry localities showed the potential of genus-level pollen data to reflect precipitation gradients. Pollen spectra also reflected mid-elevation compositional changes well along the lower elevation limit of ground cloud formation. Despite collection biases, herbarium-based bioclimatic envelope PDFs also represented well forest compositional changes along elevation gradients.