Dynamics of biodiversity of altitudinal zones in the humid climate of the Sayan Mountains: paleographic reconstructions
A.D. KOSHKAROV, V.L. KOSHKAROVA, D.I. NAZIMOVA
V.N. Sukachev Institute of Forest, Siberian Branch, Russian Academy of Sciences - a separate division of the Federal Research Center “Krasnoyarsk Scientific Center, Siberian Branch, Russian Academy of Sciences”, Krasnoyarsk, Russia
Keywords: plant macrofossils, paleocarpological analysis, Holocene, climate, succession of formations and types of vegetation, Western Sayan Range
Abstract
Based on paleocarpological data (macrofossils of Holocene plants) confirmed by 14C radiocarbon dating, a reconstruction of forest cover on a mountain profile of the northern macroslope of the Western Sayan was performed for time periods characterized by specific climatic regimes from the beginning of the Middle Holocene to the present day (7898 calendar years). The study resulted in the development of an improved method for analyzing paleocarpological material, which makes it possible to interpret the composition of plant communities of the past at local and altitudinal-zonal scale levels. The dynamics of transformations in the structure of zonal vegetation types and altitudinal complexes of forest types, conditioned by the cycles of climate change and the influence of anthropogenic impacts during the last stages of the Holocene, has been revealed. For each time period, distribution patterns of dominant forest formations in different altitudinal zones were constructed - from subtaiga and forest-steppe to mountain dark coniferous taiga and subalpine sparse forests and tundra. Their identification was based not only on the predominance of macrofossils of certain forest-forming plants, but also on the species composition of various ecological-cenotic groups of plants of the herbaceous-dwarf shrub layer. Particular attention was paid to the participation of representatives of belt-zonal groups in the fossil complexes.
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