Multivariado

Multivariate Analysis of Ecological Data
Jan Lepš & Petr Šmilauer

Faculty of Biological Sciences, University of South Bohemia eské Bud jovice, 1999

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Foreword
This textbook provides study materials for the participants of the course named Multivariate Analysis of Ecological Data that we teach at our university for the third year. Material provided here should serve both for theintroductory and the advanced versions of the course. We admit that some parts of the text would profit from further polishing, they are quite rough but we hope in further improvement of this text. We hope that this book provides an easy-to-read supplement for the more exact and detailed publications like the collection of the Dr. Ter Braak' papers and the Canoco for Windows 4.0 manual. In additionto the scope of these publications, this textbook adds information on the classification methods of the multivariate data analysis and introduces some of the modern regression methods most useful in the ecological research. Wherever we refer to some commercial software products, these are covered by trademarks or registered marks of their respective producers. This publication is far from beingfinal and this is seen on its quality: some issues appear repeatedly through the book, but we hope this provides, at least, an opportunity to the reader to see the same topic expressed in different words.

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Table of contents
1. INTRODUCTION AND DATA MANIPULATION ......................................7
1.1. Examples of research problems............................................................................................... 7 1.2. Terminology ............................................................................................................................. 8 1.3. Analyses.................................................................................................................................. 10 1.4. Response (species) data.......................................................................................................... 10 1.5. Explanatory variables ............................................................................................................ 11 1.6. Handling missing values......................................................................................................... 12 1.7. Importing data from spreadsheets - CanoImpprogram ....................................................... 13 1.8. CANOCO Full format of data files ........................................................................................ 15 1.9. CANOCO Condensed format ................................................................................................ 17 1.10. Format line........................................................................................................................... 17 1.11. Transformation of species data ............................................................................................ 19 1.12. Transformation of explanatory variables ............................................................................ 20

2. METHODS OF GRADIENT ANALYSIS.................................................22
2.1. Techniques of gradient analysis ............................................................................................. 22 2.2. Models of species response to environmental gradients ........................................................ 23 2.3. Estimating species optimum by the weighted averaging method .......................................... 24 2.4.Ordinations............................................................................................................................. 26 2.5. Constrained ordinations......................................................................................................... 26 2.6. Coding environmental variables ............................................................................................ 27...