The class Mulgedio-Aconitetea in Siberia

A new concept of classification of South Siberian tall-forb vegetation using the Braun-Blanquet approach has been developed on the basis of a geographically wide ranging set of original data and available published data. Two main phytosociological types of tall-forb meadows were distinguished within the European-Siberian class Mulgedio-Aconitetea. The thermophilous and moderately thermophilous tall-forb communities of the order Trollio-Crepidetalia sibiricae were included in four alliances: 1. Cacalio hastatae-Aconition septentrionalis (tall-forb meadows occurring in the subnemoral belt at altitudes of 259-700 m); 2. Triseto sibiricae-Aconition septentrionalis (tall-forb meadows occurring in the dark-coniferous taiga belt at altitudes of 800-1700 m); 3. Aconito pascoi-Geranion albiflori (subalpine tall-forb meadows and krummholz occurring at altitudes of 1000-1900 m); 4. Trollio asiaticae-Crepidion sibiricae (hygrophilous and meso-hygrophilous tall-forb meadows occurring in the permanently wet drained sites of various altitudinal zones). The order Schulzio crinitae-Aquilegietalia glandulosae (alliance Schulzio crinitae-Aquilegion glandulosae) includes the cryophilous subalpine tall-forb meadows with participation of alpine and arctic-alpine species which occur in the high-mountain regions of Southern Siberia at altitudes of 1700-2000 m. 26 associations, 8 subassociations and 1 variant are represented in synoptic table, their phytosociological and ecological peculiarities are briefly described. The DCA ordination of the lower syntaxa revealed clear differences in floristic composition of the higher units. Chorological analysis performed showed the peculiar plant geographical relations of altitudinal types of tall-forb vegetation and difference in their genesis.