Preliminary results of palynological investigation of bottom sediments from lake big miassovo (Chelyabinsk region, Russia)

Abstract

© SGEM 2019. The preliminary palynological results of analysis a 524 cm long continuous sediments core from the Lake Big Miassovo (South Urals, Russia) are presented. The core was collected in July 2018 from central part of the lake from a depth of 24 m. Palynological stratigraphy has been divided into four pollen zones on the basis on changing pollen abundances and taxa composition. The predominance of Betula pendula, Pinus sylvestris and Artemisia pollen in sediments has been established. The prevalence of desert plants (Artemisia, Chenopodiaceae) and low pollen concentrations in the bottom of the core indicates noticeably colder and drier climate then today. The change of dominant groups of vegetation is observed in middle layers of the core: An increase of the rate of arboreal pollen (Betula, Pinus, Picea), while the rate of herbaceous taxa declines. The occurrence of broad-leaved trees pollen (Tilia, Corylus and Ulmus) represents the climatic improvement. The upper layers of the core are characterized by an increase in concentration of pollen in the sediments and the development of birch forests and presence decline of broad-leaved species in the forest stand.