Flora of the salt dome formations of the Northern Caspian Sea: report I. Analysis of the flora of the Bogdinsk-Baskunchak salt dome district

This publication opens a series of articles on the flora of the salt-dome uplifts of the Northern Caspian Sea. On the territory of the Bogdinsko-Baskunchak salt dome region, within the Bogdinsko-Baskunchaksky State Nature Reserve and the Baskunchak regional natural park, 596 taxa of vascular plants from 305 genera and 73 families were identified, of which 560 are native and 36 are adventive. A multifaceted analysis of the native flora showed that the leading position of Asteraceae and Poaceae in the composition of the analyzed flora is characteristic of the floras of the East European Plain, the Caucasus, Western Siberia and the Astrakhan region. The third largest number of species in the family Amaranthaceae, including Chenopodiaceae, is unique in comparison with other Eastern European floras and undoubtedly reflects the influence of the desert floras of Turan, Western and Central Asia. The relationship between ecological and phytocenotic groups in the native flora of the Bogdinsko-Baskunchak salt dome region indicates the border position of the studied area on the border of steppe and desert natural zones. The leading role in the composition of the studied flora is played by species of the Mediterranean geographical element. The spectrum of life forms of native flora, according to the classification of I.G. Serebryakov, is typical of the floras of temperate arid regions of the Ancient Mediterranean region. A significant proportion of herbaceous monocarpics, shrubs and subshrubs in the composition of the flora under study reflects its border position on the border of the steppe and desert zones. The Khvalynsk transgression of the Caspian Sea and salt dome tectonics had the greatest impact on the formation of the flora of the study area. They identified anomalous landscape features and a unique species composition of the flora of the Bogdinsko-Baskunchak salt dome region. The local endemic of the Bogdinsko-Baskunchak salt-dome region that goes by the name Poacynum kazakevichii is what gives the area its uniqueness. The range of this species is limited to an area of 100 m2.