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The paper presents isolation basin stratigraphy in bottom sediments from nine lakes in the Teriberka area on the Kola Peninsula, northwestern Russia. Isolation contacts in these basins, identified from lithological and diatom analysis, were used together with 25 radiocarbon dates, to construct a relative sea-level (RSL) curve for the Holocene. Records of marine water re-influx were found in the sediment sequence from one lake, located at c. 17 m a.s.l. The re-influx of marine water seems to be caused by the mid-Holocene (Tapes) transgression and tsunami event. The RSL curve indicates several phases in the postglacial evolution of the Kola coast. An early phase of rapid sea-level fall of c. 32 m around 11,500 cal yr BP, at a rate of c. 40 mm per year, corresponds to glacio-isostatically induced emergence following deglaciation at the Younger Dryas and beginning of the Holocene. In the time interval between c. 11,000 and 7600 cal yr BP, either a stillstand or a slight rise in relative sea level, cresting at about 21 m a.s.l., is suggested in the Teriberka area. This is followed, after c. 7300 cal yr BP to the present day, by a slow glacioisostatic emergence with an average rate of about 2–3 mm per year. [ABSTRACT FROM AUTHOR]

This article presents the generalization results of studying the long-term history of paleofires in the world and on the territory of Russia specifically. Perspective and reliable methods of reconstructing the local and regional dynamics of paleofires – micro- and macro-charcoal analyzes, are considered. In the article, we analyze approaches to the study of paleofires, methods of processing and identifying micro- and macroscopic charcoal particles, including the state-of-the-art software tools for their identification ("The Charcoal Quantification Tool", "WinSEEDLETM") and analysis ("CharAnalysis") based on a review of world and Russian scientific achievements. In addition, the possibilities of modern international paleofire databases (Global Charcoal Database, Reading Palaeofire Database), which contain up-to-date information on local and regional paleofire data in the Holocene, are considered here. The results of the study of paleofires globally and on the territory of Russia in particular are analyzed and possible research directions along with fire reconstruction issues are highlighted. The review of Russian publications has shown that the central and south parts of the East European Plain, as well as the southeast of Western Siberia, are the most studied regions in terms of reconstructing the dynamics of paleofires. Few similar studies were carried out in the Urals Mts., Eastern Siberia and the Far East, but most of the regions of Russia remain understudied in this regard. In recent years, Russian researchers are mainly focused on the study of local fire dynamics based on the use of macro-charcoal analysis. The analysis of international paleofire databases (Global Charcoal Database, Reading Palaeofire Database) shows that these data need to be radically revised in relation to key sites in Russia. The authors present a generalized scheme-map of Russia indicating the key areas where paleofire dynamics were reconstructed using micro- or macro-charcoal analyzes. [ABSTRACT FROM AUTHOR]

A core of bottom sediments of 4.98 m depth has been taken from Lake Rubskoe, Ivanovo area (central part of the East European Plain). According to radiocarbon dating, the age of the lower layer of the core is 11 000 cal BP. A study of 23 samples has revealed the remains of 38 taxa of Cladocera (Crustacea: Branchiopoda). According to Lyubarsky's scale, there are no dominant taxa among the cladocerans; Chydorus cf. sphaericus (Müller, 1776) and Bosmina (Eubosmina) cf. longispina (Leydig, 1860) are subdominant taxa. Typical arctic species that had inhabited the lake at the earlier stages of its formation were replaced by taxa that preferred temperate conditions during the development of the water body. Four faunistic zones have been identified on the stratigrhaphic diagram of the cladoceran community of Lake Rubskoe. An increase in the proportion of Bosmina (Eubosmina) cf. longispina in the layers of 8500 cal BP may have been related to an increase of the pelagic area of the water body at that period. In many cases, it is obvious that the rates of certain taxa in the taphocoenosis of Lake Rubskoe correlate with the climatic changes reported at that time. [ABSTRACT FROM AUTHOR]

The problems of diagnostics of the beginning of agrarian development of coniferous–broad-leaved forests in northwestern European Russia and its specificity regarding changes in the zonal forest cover and its anthropogenic modifications inherent in the forest and field-meadow landscape based on studying pollen spectra from key sections. It was established that the onset of the agrarian development of the forests in the region under consideration dates back to 2300–2600 cal years BP. Judging by the continuous presence of cultivated plant pollen in the diagrams, it becomes ubiquitous and irreversible after 1500 cal years BP. The corresponding indicators and plants are given. The presence of plant pollen grains in the diagrams makes it possible to establish the time and nature of agrogenic changes in the vegetation composition. [ABSTRACT FROM AUTHOR]