Characteristics of perch fish diet in small lake of Lake Onega catchment area

Fish feeding process is studied as one of the links in the transformation of the energy of a water reservoir, as one of the factors that determine the ecology of fish and make an imprint on the morphology, physiology and behavior of fish, or as one of the criteria, which help the most rationally use natural resources of the water bodies. The results of work carried out by the Northern Water Problems Institute (NWPI KarRC RAS) and Petrozavodsk State University (PetrSU) within the framework of state assignments, forecast problems and economic contractual topics on assessing the nutrition of perch species (perch, ruff) in some lakes of the Konchezero group (South Karelia), in particular Lake Munozero, which is part of the lower reaches of the river Shuya belonging to the catchment area of Lake Onega. The work was carried out by the experts from the IWPS KarRC RAS and PetrSU in 2018-2020. Its main hydrological and ichthyological indicators have been studied. The reconnaissance fish productivity of Lake Munozero based on the development of the forage base at the present stage is estimated as 9 kg/ha. The feeding spectra of ruff and perch in the lake overlap only with respect to eggs, the ruff using eggs more actively. Predation is peculiar only to perch, while even fish whose size is less than 14 cm (the average size of the transition to predation for Karelia) hunt at a time when there is a lot of other food in the reservoir. As the perch passes to summer feeding, its diet becomes more diverse. Some benthic organisms are replaced by others, an air fraction appears, the perch's diet includes fish in summer and spring; nutrition becomes more active: the average stomach fullness index increases from 7.3 to 145.6‰.

On the origin and chronology of the asbestos-tempered pottery with the geometric style of decoration of Vojnavolok type

The article presents investigations of the chronology of the Eneolithic asbestos-tempered Ware with the geometric style of decoration (Vojnavolok type) and factors responsible for the massive adoption of asbestos in the ceramic production and exchange in North-Eastern Europe. According to AMS dates, Vojnavolok type is dated to ca. 3500-3300 calBC, while conventional datings made of charcoal samples from dwellings place its existence in the period ca. 3300-3100 calBC. The main component in the appearance of Vojnavolok pottery traditions was the Rhomb-Pit Ware of the Lake Onega region. Basing on our data, it can be proposed that the emergence of the Asbestos Ware with the geometric style of decoration was triggered by the emergence of a new social entity, which consisted of productive units interacting in the sphere of making objects for “prestige” exchange.

Kargopol ceramics: a separate type or a variety of pit-comb ceramics (on the example of materials from the settlements of Karelia)?

The purpose of this study is to consider the phenomenon of Kargopol ceramics in Karelia, which is manifested in its bright originality, sharp difference from other types of Neolithic ware and the vastness of the area-from Lake Onega in the west to the Pechora River in the east and from the Southern White Sea in the north to the southern limits of the Vologda Region in the south. There are 20 known settlements in Karelia, the complexes of which contain Kargopol ceramics with a total number of 275 vessels. The center of this layer of antiquities is Lake Vodlozero, located near the border of Karelia with the Arkhangelsk Region. Most Kargopol vessels have a straight flat-cut corolla with short and shallow notches applied from the outer and inner edges, below there is a horizontal belt of pits or punctures. There are six variants of ornamentation, three of which include elements of pit-comb and comb dishes. The authors think that the concentration of Kargopol vessels on the monuments of eastern Karelia, mainly in the complexes with pit-comb ceramics of the middle stage of development in the lake basin Vodlozera, and its almost complete absence in other areas of Karelia indicates the penetration of a similar ceramic tradition from the Eastern Prionezh Region, where it was first isolated. Based on the available modern data, it is still difficult to talk about the independent existence of Kargopol ceramics in the Neolithic of Karelia.

Konstantin Kuzmich Loginov: The Milestones of the Ethnographer’s Life

This article is dedicated to the memory of Konstantin Kuzmich Loginov (1952–2020), a first-rate professional ethnographer, who worked at the Institute of Linguistics, Literature and History of the Karelian Research Center of the Russian Academy of Sciences. The article presents a biographical study of the most important stages of the researcher’s life and an analysis of his scholarly activities. Loginov is known as the foremost scholar of the ethnic history and the traditional culture of the Russian population of Karelia and of the features of its ethno-local groups. He is the author of about 185 research articles in which he applied descriptive and comparative-historical methods to the rich field material that he himself collected. Loginov’s most significant works are the five books (including one co-authored) devoted to the study of the Russian population of the north shore of Lake Onega (Zaonezhye) and territories around Lake Vodlozero (Vodlozerye). He is also the author of chapters in seven major collective scholarly works, including books about the Karelian settlements of Suisar, Yukkoguba, and Syamozero. The last work of this kind was the book The Peoples of Karelia. Historical and Ethnographic Essays. Loginov also devoted much time and effort to such scholarly activities as expeditions, presentations at conferences, popularization of ethnographic knowledge, and teaching.

GEOECOLOGICAL REGULARITIES OF THE MOLYBDENUM AND TUNGSTEN DISTRIBUTION DURING ANTHROPOGENIC TRANSFORMATION OF THE GEOSYSTEMS OF PRIONEZHYE

Molybdenum and tungsten in polluted geosystems have been insufficiently studied. The goal of this work is to compare the distribution of Mo, W and Mo/W ratio in the components of geosystems near the western shores of Lake Onega. To achieve this goal, the content of the metals in soils, bottom sediments, river water and, additionally, street dust and road asphalt was determined, dependence graphs were constructed, linear correlation coefficients were calculated. The most polluted soils are those in the central part of Petrozavodsk, while the least polluted are those in the rest of the city. The geometric mean content of Mo and W is maximum in the fraction < 0,1 mm of the soils at the former Onega Tractor Plant site (20,9 and 70,9 mg/kg, respectively); the content is lower in large fractions 1,0–0,1 mm (4,84–8,26 and 15,6–26,3 mg/kg). Mo/W ratio in the soils of the industrial site is on average lower than in the soils of the rest of the city. The soils of the South-Western Onega region are not polluted with the studied metals. There is no statistically significant correlation between Mo and W in most soils, with the exception of the most contaminated ones. Bottom sediments of the urban Lososinka River contain an average of 2,70 mg/kg Mo and 3,73 mg/kg W, while the suburban section of the Shuya River contains 0,573 and 0,572 mg/kg, respectively. In the urban river water, the geometric mean of Mo/W ratio varies from 0,090 (dry weather) to 0,385 (rain). Both values differ considerably from the literature data due to significant tungsten contamination. When conducting geoecological monitoring in the future, more attention should be paid to various sources of harmful metal pollution. These studies are important for reducing health risks associated with pollution.

QUATERNARY DEPOSITS AND GEOMORPHOLOGICAL FEATURES OF LAKE ONEGA

Many publications have been devoted to the geological and geomorphological study of both Lake Ladoga and Lake Onega – the largest lakes of Northwest Russia and Europe. The last comprehensive geological studies of Lake Onega were carried out by Polar Marine Geosurvey Expedition as part of a geological survey at a scale of 1: 500,000 [12] and by Finnish researchers [19] at the beginning of the 21st century. Subsequently, these data were included in the third-generation State Geological Map at a scale of 1:1 000 000 [13]. Study of the basin’s geological structure was resumed in 2016 by researchers from the Northern Water Problems Institute of the Karelian Research Center of the Russian Academy of Sciences, St. Petersburg State University, Lomonosov Moscow State University and Herzen State Pedagogical University of Russia, as well as representatives of other scientific organizations. The works included geological sampling, drilling from ice platform, seismoacoustic profiling and side-scan sonar. The aim of the works was to clarify data on the structural features of the Upper Pleistocene and Holocene deposits of Lake Onega and the genesis of the lake basin relief. Based on the data obtained in the course of field studies, a new distribution scheme of the Lake Onega Quaternary deposits was drawn up. Comparison of the scheme with the data on the bottom topography made it possible to characterize its genesis and draw up a geomorphological scheme. The data presented in this article can be used to update and supplement the State Geological Map of the Northwest Russia, as well as to solve other problems of Quaternary geology and paleogeography.

Geochemical characteristics of bottom sediments of Lake Onega

The subject of this article represents results of scientific studies in 2018–2019. The studies indicate that the phenomena of gas saturation of bottom sediments are often observed within the Lake Onega. Basically, this occurs in the mouths, while in the open part of the lake the degree of gas saturation of the sediments is incomparably less. According to the geo-chemical studies, numerous signs confirmed the predominantly biogenic origin of gases.