Genetic-Demographic Parameters of the St. Petersburg Population. Migration Processes
The determination of the main genetic-demographic parameters of migration processes which are significant for studying the structure of the St. Petersburg population gene pool is based on the analysis of demographic statistics of the Petrostat, the All-Russian population censuses and data from a sample survey of St. Petersburg residents. The migration coefficient, calculated according to the questionnaire, is 0.36; calculated according to the 2002 census data – 0.42; according to the 2010 census – 0.44, and according to the 1897 census, 0.69. The average migration distance estimated from the survey data is 1746 km; according to the 2002 census, 1,526 km; the 2010 census – 1652 km. The data on the sources of the St. Petersburg population gene pool at different epochs are presented: in the XVIII and XIX centuries the main source was the population of the U-pper Volga and North-Western provinces of the Russian Empire, as well as foreigners; at the present stage the population gene pool is formed by 3/4 from the population of the North-West Federal District, by 10% due to natives of foreign countries and only by 6–9% due to the population of the Central Federal District of the Russian Federation. An analysis of the Rosstat migration statistics showed that the composition of migrants by countries of exit is unstable over time: the share of migrants who arrived in St. Petersburg from Russia varies from 74 to 87%; in 2013 – 2014 the majority of international migrants came from Uzbekistan (10% of all arrivals) and Tajikistan (3–4%); in 2017, Kyrgyzstan ranks first in the number of migrants (almost 4%); in the second – Ukraine (about 2%), in the third – Belarus (1.5%); on the fourth – Kazakhstan (1.25%); on the fifth – Armenia (1%). Migration processes determine the dynamics of the ethnic composition of the population. Gender differences in migration flows are manifested in different age structure and in unequal sex ratio among different ethnic groups (the numerical predominance of men among the representatives of the “young” ethnic diasporas – Armenians, Azerbaijanis, Uzbeks). Identified in this study, the features of migration processes in St. Petersburg should be considered when forming databases on genetic markers for the purpose of DNA identification. The areas of migration attraction of St. Petersburg and Moscow overlap only partially, which predetermines the need to create separate databases for each megalopolis.