Search

Aim: Forest-steppe complexes in the peri-Carpathian region harbour specific vegetation dominated by tall herbs. Our aim was to provide new phytosociological data on this vegetation type from the Ukraine and adjacent parts of Romania, compare it with previously published data, discuss its position in broad ecological and biogeographical context and suggest its syntaxonomic treatment respecting both its physiognomy and species composition. Study area: Western Ukraine and Romania. Methods: We assembled a dataset of 711 relevés of thermophilous herb-rich vegetation (Trifolio-Geranietea) from the study area and adjacent regions of Eastern Poland and Slovakia using own field research, literature survey and large databases. Using intersection of three different classification algorithms (beta-flexible, modified TWINSPAN and K-means clustering) we identified a consensus delimitation of the vegetation type. NMDS ordination, analysis of diagnostic, constant and dominant species, and Didukh indicator values were used to characterize its species composition and habitat conditions. Results: Altogether 58 relevés from Western Ukraine and Romania were classified to a tall herb-dominated vegetation type that we identified with the association Trollio-Clematidetum recti Täuber et Weber 1976 described from Romania. We assigned it to the alliance Geranion sanguinei. It differs from other communities of this alliance in its preference for shady slopes, greater stand height and considerable representation of mesophilous and montane species. It is confined to calcareous bedrock with high soil pH and high mineral richness. Conclusions: We suggest that the studied tall herb-dominated vegetation is a specific steppe type, confined to relatively moist and nutrient rich sites in the peri-Carpathian area. Analogous vegetation occurs in the Alps, Balkans, hemiboreal Europe, South Urals and Western Siberia. Its species composition and biogeographical relationships provide further support for the hypothesis that steppe meadows of Central Europe, including tall herb-dominated stands, are linked to the Pleistocene and early-Holocene forest-steppe of temperate Eurasia. [ABSTRACT FROM AUTHOR]