ИСТИНА

The new results from paleoecological studies of vegetation and fire history over the last 8500 years in the south-eastern part of the Meshchera Lowlands based on pollen, plant macrofossils, testate amoebae and charcoal records from peat sequences are presented. Changes in woody coverage were reconstructed using the Best Modern Analog technique which allowed us to assess responses of vegetation to fire disturbance in the past. The obtained results showed that most of the changes in the regional vegetation during the Mid- and Late Holocene were mainly influenced by the climate and fire regime. Since 8500 cal yr BP, the vegetation history represented a series of consecutive phases of birch, birch-pine and pine-broadleaf forests with participation of spruce after 2500 cal yr BP. The maximal abundance of broadleaf tree species was detected for the period of 4700-2000 cal yr BP. Since 1400 cal yr BP, vegetation dynamics were strongly influenced by human activity. High fire frequencies were reconstructed for the periods of 8500-5000 cal yr BP and 3000-2000 cal yr BP, when the fire return period varied from 70 to 200 years. The fire frequency reduced in the last two millennia, while the fire return period increased to 200-500 years.