Paleoenvironmental reconstruction of climate by diatoms from sediments of three deep freshwater lakes of Evenkia (Siberia, Russia)

Abstract

The study aimed to determine the species composition of diatoms in the bottom sediments of the freshwater lakes Zapovednoye, Cheko, and Peyungda, situated in the taiga zone of the southern region of Evenkia within the boundaries of the Tungussky State Nature Reserve. A total of 255 taxa have been identified in these lakes, with their ecological characteristics also established. The diatom community present in the bottom sediments of the aforementioned lakes showcases species that are common across all three lakes, as well as some that are exclusive to every single reservoir. An examination of the acquired data indicated the existence of overarching trends in the evolutionary trajectory of lakes Cheko, Zapovednoye, and Peyungda. Nevertheless, discernible discrepancies are observed in the species composition of diatoms within their bottom sediments, both in terms of quality and quantity, thereby delineating Lake Peyungda in a distinctive position in comparison to lakes Zapovednoye and Cheko. This disparity is likely attributed to the relatively shallow depth of Lake Peyungda, leading to an inclination towards a heightened level of eutrophication in its species composition, as opposed to the conditions observed in lakes Cheko and Zapovednoye.