Решением президиума Высшей аттестационной комиссии журнал включен в перечень ведущих рецензируемых научных журналов и изданий, выпускаемых в Российской Федерации, в которых должны быть опубликованы основные научные результаты диссертаций на соискание ученой степени доктора и кандидата наукЮГ РОССИИ ЭКОЛОГИЯ, РАЗВИТИЕ

No abstract

A high variyety of vegetation and a predominance of small cell forms are typical of the current structure of the phytoplankton of the seacoastal shallow waters of the Russian coastline of the Caspian Sea. The replacement of the dominating complex and the size groups of the phytoplankton has occurred. The phytoplankton community is represented by six categories: Cyanophyta, Bacillariaphyta, Dinophita, Euglenophyta, Chlorophyta, and the small flagellates. The basis of the taxonomic variety consists of the Diatoms algae. The composition of species of the phytoplankton of the sea coastal shallow waters of the Russian water area of the Middle Caspian is in a dynamic state and depends on the direction of the change of water regime.

The latitudinal variability of the linear and allometric growth of didacna has been revealed. The tendencies of increase in the increments and the elongation coefficient with approach to the optimal conditions in temperature and soil have been found, herewith the convexity coefficient decreases. The life span of didacna is inversely proportional to the growth rate.

The study of the biocomplexes of the Khazar horizons of the Dagestan coast of the Caspian Sea and the identification of faunal criteria for recreating the habitat conditions of paleobassins, which allows for more reliable reconstructions of individual stages of the Late Eopleistocene. Biostratigraphic and morphometric research methods were used to study the Khazar sediments and the mollusks contained in them. Various didacn complexes allow us to stratify the sediments containing them in detail. Changes in the composition of fauna in the section of marine sediments are mainly associated with environmental conditions and the nature of sedimentation, which allows us to indirectly use the change of different facies complexes as a periodization of sediments. The biostratigraphy of the Caspian Late Eopleistocene is based on evolutionary changes and patterns of ecological change in the communities of mollusks of the genus Didacna Eichwald in space and time. The study of the conchylofauna of the Khazar horizons of the Dagestan region of the Caspian Sea showed that two groups of crassa and trigonoides mollusks are mainly represented in the complexes, and the leading and characteristic species are identified. The analysis of the distribution of the main groups of didacnas by section, the stability of their composition and intergroup differences indicates a high reliability of the division of the Caspian sediments on this basis.