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New World palm (Arecaceae) species richness in relation to mean climate variables. University of Arizona Semester Project, ATMO 529 Brad Christoffersen December 05, 2007. Outline. Background & Motivation Methods of Analysis Upcoming Results Summary. Background and Motivation.
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New World palm (Arecaceae) species richness in relation to mean climate variables University of Arizona Semester Project, ATMO 529 Brad Christoffersen December 05, 2007
Outline • Background & Motivation • Methods of Analysis • Upcoming Results • Summary
Background and Motivation • A little about palms: • Family: Arecaceae • Diverse habitats and hence morphologically diverse • Key terms: • Species Richness (or Alpha diversity) – The number of species in a given area. • Beta diversity – Change in species composition across a landscape from one area to another. • Why study species diversity in a spatial context? • Insight into how limiting factors control evolutionary processes of speciation and extinction. • Provides basis for development of conservation areas. • Extensive body of theory from community ecology.
Methods of Analysis • Palms dataset: • What: 1x1 degree grid of presence/absence data for 547 species of palms. • Spatial Extent: New World • Calculated species richness by grid cell. • Climate data: • What: CRU TS2.1 0.5x0.5 degree grid of monthly precip and average temperature • Spatial Extent: Brazilian Amazon • Plant rooting depth: • What: Maximum Plant Available Water (PAW), from Kleidon et al. 2002
Methods of Analysis • Palms dataset (Henderson et al. 2005): • Structure into presence/absence for the 547 species. • Convert to relative abundance (0-1) • EOF analysis of the matrix. • Examine spatial pattern correlation among climate and dominant species range modes.
References • Henderson, A., G. Galeano, and R. Bernal. 1995. Field Guide to the Palms of the Americas. Princeton University Press, Princeton, New Jersey, U.S.A. • R Development Core Team (2007). R: A language and environment for statistical computing. R Foundation for Statistical Computing, Vienna, Austria. ISBN 3-900051-07-0, URL http://www.R-project.org. • Fields Development Team (2006). fields: Tools for Spatial Data. National Center for Atmospheric Research, Boulder, CO. URL http://www.cgd.ucar.edu/Software/Fields. • Ter Braak, C. J. F. (1986) Canonical correspondence analysis: A new eigenvector technique for multivariate direct gradient analysis. Ecology 67:1167-1179.