Impact of natural and anthropogenic factors on dynamics of fires in the Holocene of Central Asia and Siberia according to macro-charcoal analysis

The article presents an overview of the Holocene paleofire records based on the analysis of macro- and micro-charcoals from Siberia and Central Asia. The method of charcoal analysis for reconstructing paleofires involves extraction of charred particles from paleoarchives and analysis of their distribution over the depth of the sediments. The structure of macro-charcoals makes it possible to determine the initial type offuel (wood or grass). Distribution of charred particles of various sizes at different depths indicates the distance of fires in different periods ofpalaeoarchive accumulation. A separate area of reconstruction analysis is identification of key factors contributing to increasedfire frequency. For this purpose, natural factors (climatic parameters), anthropogenic factors, and their interaction were analyzed. For establishing the most significant factor, the reconstructed dynamic pattern offires was compared with climate change and vegetation dynamics (obtained from independent paleoecological reconstructions), taking into account geographical location, ecology of the area as well as archaeological data on the population and types of economic activities in different periods. At this stage, there are only a few records obtained by the macro-charcoal method for Southern Siberia, and the best-studied region is Mongolia. Several lakes in Kyrgyzstan have been investigated using the micro-charcoal method. Based on the available data, it can be concluded that the leading factors in increase of fire activity during most of the Holocene were natural causes mainly associated with periods of decreased climate humidity. In the last 1500-1000 years, with continuing decrease in humidity, anthropogenic impact has started to play an active role due to increase in population density in the region and human economic activities. Only for the last 100 years, all records of Central Asia and Siberia show increasedfire activity associated with industrialization and climate warming.