Sunday, August 3, 2008: 8:00 AM-5:00 PM
Lapham Hall, Room 280, University of Wisconsin Milwaukee
Organizer:
David Roberts, Montana State University
Co-organizers:
Stefan A. Schnitzer, University of Wisconsin - Milwaukee; and
M. Forbes Boyle, University of North Carolina - Chapel Hill
The National Vegetation Classification (NVC) is a collaborative effort among vegetation scientists, the ESA, NatureServe, and federal natural resource agencies to develop a comprehensive, data-driven classification of the vegetation of the United States. The NVC requires supporting vegetation analysis for all proposed vegetation types (Alliances and Associations), but does not prescribe specific analyses that must be conducted. This workshop will focus on a hands-on approach to exploring the range of multivariate analyses available for vegetation analysis, including ordination, classification, and indicator species analysis. Workshop attendees will work at computer workstations on vegetation data provided by the organizers, and will explore the broad range of analyses available in the open-source statistical package R. Attendees will be given copies of the software for future use on their own computers and data. The R statistical package provides state-of-the-art analytical routines and graphics. We will focus on: (1) vegetation dataset visualization (heterogeneity, dominance/diversity, species richness, and species distributions), (2) graphical analysis of environmental variability (empirical cumulative density functions, boxplots, scatterplots, and distribution functions), (3) hierarchical and non-hierarchical cluster analysis, cluster validity assessment through geometric evaluators, and non-geometric indicator species assessments, and (4) ordination analysis of vegetation clusters and environmental drivers using non-metric multidimensional scaling (NMDS), fuzzy set ordination (FSO), and canonical correspondence analysis (CCA). Workshop attendees will gain working knowledge on the use of a broad range of multivariate analyses useful in community ecology, and workshop organizers will gain a better understanding of the relative utility of specific analyses in vegetation classification.