TAXONOMIC DIVERSITY OF THE FABACEAE ON THE TERRITORY OF SAMARA-ULYANOVSK REGION
The flora of фSamara-Ulyanovsk Volga Region belongs to the Fabaceae type (the third place in the family spectrum), while having inclusions of other types of local flora. The study examines how homogeneous is the species representation of the genera of the Fabaceae family throughout the research area. The authors used 445 floristic lists from the FD SUR database as source data. Based on these lists, the authors obtained combined lists of all the floras and their generic and family spectra. The heterogeneity of the composition of the Fabaceae family at the generic and species levels was studied in 12 physical-geographical regions. The authors identified 15 reference floras in six of examined regions, where the lists of vascular plant species include 700 species. The area of the identified reference floras is 300–900 km2. The general list of the Fabaceae family in the research area includes 113 species from 23 genera. The genus Astragalus L. is at the top of the genera. The other large genera are Vicia L. and Lathyrus L. The authors registered some differences from the overall picture for certain physical and geographical areas. This is the consequence of various local environmental conditions in the research area. In some cases, the genus Vicia becomes the most abundant, but the distribution of Astragalus becomes rather small. The genus Lathyrus does not always hold the third place in the spectrum. The considered reference floras are nominally divided into three groups according to the composition of the generic spectrum of the Fabaceae family: the flora group with numerical dominance of the genus Astragalus, the group with predominance of the genus Vicia and the group in which the genus Trifolium L. and Amoria C. Presl. form the basis of the composition. The first two groups are characterized by the multiplicity of the corresponding genera in comparison with others. On the contrary, the composition of the third group is explained by the relative paucity of genera Astragalus and Vicia. The composition and abundance of the genera Trifolium and Amoria are the most stable in all considered floras. The authors note the lack of uniformity in the order of leading genera of the Fabaceae family in Samara-Ulyanovsk Volga region.