Simultaneous analysis of a sequence of paired ecological tables: A comparison of several methods

Abstract

A pair of ecological tables is made of one table containing environmental variables (in columns) and another table containing species data (in columns). The rows of these two tables are identical and correspond to the sites where environmental variables and species data have been measured. Such data are used to analyze the relationships between species and their environment. If sampling is repeated over time for both tables, one obtains a sequence of pairs of ecological tables. Analyzing this type of data is a way to assess changes in species-environment relationships, which can be important for conservation Ecology or for global change studies. We present a new data analysis method adapted to the study of this type of data, and we compare it with two other methods on the same data set. All three methods are implemented in the ade4 package for the R environment.