Supplement 1. The data sets as well as the R code to perform a contribution biplot in correspondence analysis.

File List all_files.zip (md5: 05899eadd594e72909c652856b0255fa) benthos.csv (md5: 3967c416398c06a5a1c37ee4213ed601) barents.csv (md5: 4784e8a75f12c8d54c4e75972e5e45ff) macro.csv (md5: ec932c53204636c4d9bc0eda978b4161) seashore.csv (md5: d51a0a57aed6c42ed903280c8ac3a1d0) texel.csv (md5: f06123b443e088d941dae5c8709be649) CAbiplot.R (md5: 92afeea2ed19440632b3dac5c8a1b069) Description all_files.zip is an archive containing all data and code described below (6 files). benthos.csv is a comma-separated text file containing the 'benthos' dataset used in the main body of the report. Column definitions are: 1. station id: Sx for 11 polluted stations, Rx for 2 reference stations 2–93. abundances of 92 benthic species barents.csv is a comma-separated text file containing the 'barents' dataset. Column definitions are: 1. benthic species id (abbreviated) - 446 species 2–11. abundances at 10 sampling sites macro.csv is a comma-separated text file containing the 'macro' dataset. Column definitions are: 1. sample id - 40 samples 2–198. abundances of macro-invertebrates from two Dutch streams seashore.csv is a comma-separated text file containing the 'seashore' dataset. Column definitions are: 1. sample id - 126 samples 2–69. abundances of vegetation of rising seashore in Stockholm archipelago - 68 species texel.csv is a comma-separated text file containing the 'texel' dataset. Column definitions are: 1. sample id - 285 samples 2–222. vegetation on coastal sand dune area on Texel island - 221 species Note: to align with the original publication, samples with zero abundances have to be eliminated, as well as species that have a single abundance of 1, to give a table with 209 samples and 209 species. The data set 'fish' is not available for release at the moment. CAbiplot.R is an R script file to produce a contribution biplot in correspondence analysis. This script assumes that the CA package is downloaded from CRAN. The data set should be in the working directory of R when running this code.