Динамика хозяйственного освоения Посурья в I тысячелетии н.э. Часть 1: данные стратиграфического анализа пойменных и балочных отложений

Abstract

The article summarizes the results of a comprehensive landscape-archaeological study of the dynamics of human-environmental interaction in the Middle Sura region during the first millennium AD. The data resulted from the study of the River Sura floodplain at the former confluence of the Sura and the Malaya Sarka. The analysis of the sediments and buried soils indicates that the period between the first millennium BC and the first millennium AD saw a series of climatic cycles changing each other, with the floodplain periodically being available for various types of economic development. The Early Iron Age (first millennium BC – 2nd–3rd centuries AD) saw the formation of grey forest soils in the part of the floodplain under study. During this period, the area remained uninhabited, while the population was involved in the development of the elevated terraces and riverbanks. In contrast, in the second quarter of the first millennium AD the floodplain covered at the time by broadleaf forest had the most favorable conditions for settlement; the area was developed by the population that belonged to the Middle Volga variant of the Kiev culture. Their economic activity resulted in the gradual deforestation of the floodplain, with meadow landscapes arising instead of the forest. The second half of the 5th century saw drastic intensification of the floods and an increased runoff. The sites assigned to this period represent the developed stage of the Imen´kovo culture; these were located on the elevated terraces. The new stage of low flooding dates to the medieval period (8th–13th centuries), the soils bearing traces of steppe formation and subsequent development of the floodplain. Later, in the late Middle Age and the early Modern period, tillage shifted to watersheds and intensified, while the accumulation of layered alluvial deposits on the floodplain started again, with frequent and intense floods taking place. The study of the dynamics of the moistening of the Sura floodplain is asynchronous with the data of other studied regions of the Russian Plain, which raises the question of a relationship between the availability of floodplains for economic development and migration processes.