Formalized classification of European fen vegetation at the alliance level

摘要: Phytosociological classification of fen vegetation (Scheuchzerio palustris-Caricetea fuscae class) differs among European countries. Here we propose a unified fens at the alliance level, provide unequivocal assignment rules for individual plots, identify diagnostic species alliances, and map their distribution. 29 049 vegetation-plot records fenswere selected fromdatabases using list specialist species. Formal definitions alliances were created presence, absence abundance Cocktail-based groups indicator DCA visualized similarities in an ordination space. The ISOPAM algorithm was applied to regional subsets with homogeneous plot size check whether based on formal matches results unsupervised classifications. following defined: Caricion viridulo-trinervis (sub-halophytic Atlantic dune-slack fens), davallianae (temperate calcareous atrofusco-saxatilis (arcto-alpine Stygio-Caricion limosae (boreal topogenic brown-moss Sphagno warnstorfii-Tomentypnion nitentis (Sphagnumbrown-moss rich Saxifrago-Tomentypnion (continental boreo-continental nitrogen-limited Narthecion scardici (alpine Balkan endemics), stantis (arctic Anagallido tenellae-Juncion bulbosi (Ibero-Atlantic moderately Drepanocladion exannulati (arcto-borealalpine non-calcareous Sphagno-Caricion canescentis (poor fens) Scheuchzerion palustris (dystrophic hollows). main variation composition reflected site chemistry (pH, mineral richness) sorted plots from extremely fens, through andmoderately poor dystrophic hollows.