About the coenoflora of mountain birch forests of Dagestan
Data on the coenoflora of forests dominated by Betula litwinowii and Betula raddeana in the tree layer in Alpine and Inland Dagestan based on the results of field studies 2018-2020 are presented. 103 geobotanical descriptions were performed in the Gunibsky, Charodinsky, Tsumadinsky, Laksky, Akushinsky, Tsuntinsky and Dokuzparinsky administrative districts. The total number of vascular plant species in the communities described by us is 438, of which 18 are in the tree stand, 32 are in the undergrowth layer, and 388 are in the grass-shrub layer. The species of the coenoflora of the birch forests belong to 73 families, 219 genera. The order of distribution of the leading 10 families of the coenoflora of the birch forests of Dagestan characterizes it as typical for the flora of the Holarctic kingdom. The presence of Poaceae in second place in the number of species, after Asteraceae, as well as the abundance of Ranunculaceae species (3,19%) reflect the boreal features of the coenoflora of the birch forests of Dagestan. The biomorphological spectrum is dominated by hemicryptophytes (70,32%), which is characteristic of mountain flora and also indicates the Holarctic nature of the flora. Moss-lichen layer and undergrowth of birch forests, as a rule, are poorly developed except for communities with undergrowth of Rhododendron caucasicum , the projective coverage of which reaches 90%. In the grass-shrub layer of birch forests, meadow species predominate (46,58%). Most of the dominants of the grass-shrub layer are meadow subalpine species.