ИСТИНА

The role of climate and anthropogenic factors in the Forest fire dynamics in the Western part of the Putorana plateau (Northern Siberia) last 1300 years In the context of modern climate change in the Arctic region, the study of past environmental changes is becoming increasingly important. This study aimed to the reconstruction of forest fire history determined by climate and anthropogenic factors for the Western part of the Putorana plateau (Northern Siberia). Macrocharcoal particles (size >125 µm) were analysed to reconstruct fire history. Pollen analysis was used for reconstruction of the climate, human and forest fires impact on the vegetation cover of this territory in the past. Peat sediment core from the peatland Gervi (N 69⁰28'22; E 91⁰26'50) was used for analysis. The peat column length is 64 cm. The chronology of the study is provided by 3 AMSradiocarbon dates. Peatland Gervi has 3 stages of forest fire frequency. The first stage from 1300 cal. year BP to ~900 cal. year BP characterized by 6 fire peaks (approximately 1 fire episode per 65 years) with high CHAR-index. Pollen analysis indicates for this period of warmer climatic conditions (Medieval Climate Optimum). Indicators of fire activity (Onagraceae, Gelasinospora) is found in pollen spectra. The middle part of the peat column dated ~900–100 cal. year BP has 2 fire peaks. We suppose that these peaks may be random events. This period corresponds to the Little Ice Age and according to pollen analysis is characterized by the predominance of sparse larch forests and treeless areas. The last stage (from ~100 cal. year BP to the nowadays) has only one fire peak with high CHAR-index. We suppose that relatively high CHAR for last ~100 years caused by the modern climate changes and active anthropogenic influence, which began in this region only in the 20th century because this area is remote and difficult to access.