Ordination Methods for Ecologists

JUMP TO: | OVERVIEW |  Ordination Topics | Ordination Software Links | Ordination Glossary | Other Ordination Links | Ordination Listserv | OSU Botany 

Members of the Laboratory for Innovative Biodiversity Research And Analysis (LIBRA) are often available to engage in consulting activities for particular projects, or to offer short courses on ordination methods and the use of CANOCO.  For more information, contact Mike Palmer at mike.palmer@okstate.edu.

Ordination is a widely-used family of methods which attempts to reveal the relationships between ecological communities. For definitions, go HERE.

This ordination web page is designed to address some of the most frequently asked questions about ordination. It is my intention to gear this page towards the student and the practitioner rather than the ordination specialist, so please contact me if the jargon is unintelligible!

The ecological literature is filled with papers describing, contrasting, and modifying existing ordination techniques. Then why is an ordination web page needed? My main motivation is based upon the following observation: many of us, when we start to use ordination methods, make the same simple mistakes. If we are good scientists, we will learn from our own mistakes. But wouldn't it save a lot of time if we could also learn from other people's mistakes?

It turns out that there are a number of frequently asked questions concerning ordination, as well as a number of "tricks of the trade" and "rules of thumb". It is probably not worthwhile filling the pages of our scientific journals with such rules; many of them are quite trivial. However, the Web, which is easy to update, modify, and rearrange, is an ideal forum for presenting such ideas.

As in any scientific endeavor, the field of ordination methodology is filled with conflicting opinions and world views. While I try to be objective, it is difficult to remain completely detached. I would like this to be an open forum! Please send in your comments, reactions, flames, questions, etc. if you would like to see them included in the web page! I am also very eager to accept new text and suggested links.

This web page continues to be under construction. I started with some commonly-encountered issues with respect to Canonical Correspondence Analysis (CCA), which is probably the most widely used ordination technique today. I then expanded the page to cover other ordination methods.  I would be happy to entertain suggestions as to how to expand or modify this page in the future. This website is designed, in part, as instructional material for a graduate-level ordination course, taught in Falls of odd-numbered years, at Oklahoma State University.  However, this website is not to be considered a textbook, nor a comprehensive reference source.  Please refer to suggested references for self-education to pave the way for a more thorough appreciation of ordination methods.

Mike Palmer, Botany Department, Oklahoma State University, Stillwater, Oklahoma 74078 USA
TEL: 405-744-7717 FAX: 405-744-7074       mike.palmer@okstate.edu.

Ordination Topics

General and Reference Overview of ordination methods A Glossary for terms used in Ordination Milestones in the history of Ordination Ordination terminology: some confusions The ideal ordination method Recommendations for ordination: a key Suggested references for self-education Hypothesis-driven and Exploratory Analysis Ordination links	Indirect Gradient Analysis Distance-based ordination methods Eigenanalysis-based ordination methods Principal Components Analysis Correspondence Analysis Detrended Correspondence Analysis
Statistics and Background Experimental design and sampling Basic statistical concepts Multiple Regression Randomization tests Centroids and Inertia Similarity, Distance and Difference Explorations in Coenospace	Direct Gradient Analysis Environmental Variables in Constrained Ordination (CCA, RDA) Reducing the number of variables The robustness of CCA Partial Ordination Variance explained and Variance partitioning in CCA What if the results are uninterpretable?
Practical details for running ordination Available software Running ordination using CANOCO Data formats for input into CANOCO, DECORANA, or TWINSPAN	Ecological data, transformation and standardization Species abundances in ordination On the transformation of species abundances Environmental Variables in Constrained Ordination (CCA, RDA)

This page was created and is maintained by Michael Palmer.

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