Vegetation of the ultramafic mountain massif Rai-Iz (upper reaches of the Enga-Yu River, the Polar Urals, Russia)

The syntaxonomic diversity of vegetation in the upper reaches Enga-Yu River is described. specificity study area was determined by ubiquitous occurrence ultramafic rocks, which contributed to an increase harshness habitats due high concentration heavy metals and low calcium content. Unfavorable geochemical environments caused absence several common this region species same time change ecological preferences amplitude other species. Within lower middle parts alpine belt, we distinguished described for first 4 associations 2 subassociations. Cladonio rangiferinae–Caricetum arctisibiricae ass. nov. with subassociations (C. r.–C. a. typicum subass. nov., C. dicranetosum acutifolii nov.) assigned class Loiseleurio procumbentis– Vaccinietea Eggler ex Schubert 1960. Asahineo chrysanthae–Racomitrietum lanuginosi placed into Carici rupestris–Kobresietea bellardii Ohba 1974. Two were as provisional. Tephroserido tundricolae–Bistortetum ellipticae prov. comprising snowbed vegetation, not yet any higher unit. Festuco arcticae–Caricetum comprises meadow communities, it Juncetea trifidi Hadač Klika et 1944 order Juncetalia Daniёls 1994. It alliance shortage data. peculiarity these provisional explain influence rocks.