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Appendix D. Cluster analysis dendrogram of sample points based on earthworm species biomass in 1999. The vertical dashed line indicates where the dendrogram was cut based on indicator species analysis, identifying four earthworm species assemblage groups, solid squares = sample points with Dendrobaena only; solid triangles = sample points identified by the presence of and Lumbricus juveniles and Lumbricus rubellus; empty triangles = sample points with Aporrectodea species and Dendrobaena octaedra as the dominant species; empty squares = sample points identified by the presence of Lumbricus terrestris and Octolasion tyrtaeum.