ИСТИНА

Fire frequency was reconstructed on the base of macro- and micro-charcoal concentration in peat cores from five key areas, located in different landscapes in forest zone of European Russia: southern part of Valdai Upland (the Central Forest Biosphere Reserve, south taiga), Meshchera lowlands and Mordovia State Natural Reserve (mixed coniferous-broadleaf forests) and Mid-Russian Upland (Kaluzhskie Zaseki State Natural Reserve, roadleaf forests). The obtained results showed that the beginning of human occupation of the areas is clearly marked by increased fire activity. Medieval time (at about 1000 cal yr BP) and Modern Period (the last 300 years) were marked by high fire frequencies allover the East European Plain. In the model area “Kaluzhskie Zaseki” a significant ncrease in fire frequency was revealed around 2000 cal yr BP (Early Iron Age) and the maximum frequency of fires (8 fires per 1000 years) was reconstructed for the last millennium. However, periods of increased fire activity occurred prior to the occupation of these areas by human. The highest frequency of fire in all model areas was determined for the periods 9000-6000 cal yr BP and 3500 – 2500 cal yr BP. Fire-free interval ranged from 15- 20 to 120 years. According to data available, the influence of anthropogenic factor during these time intervals was low. Archeological findings were not revealed in vicinity of the peat cores and no pollen or plant macrofossil indicators of human impact were detected.Evidently forest fires were coursed by climatic reason. The regional climatic reconstruction inferred from pollen and testate amoebae data these periods revealed high temperatures and dry summer conditions. This work was supported by the Russian Foundation for Basic Research, projects 20-05-00234