DBPapers
DOI: 10.5593/sgem2017/41/S19.075

SUBFOSSIL CLADOCERA FROM BOREAL LAKE GAHKOZERO (THE REPUBLIC OF KARELIA, RUSSIA) AS PALEOENVIRONMENTAL PROXIES

A. Ibragimova, L. Frolova, S. Dmitriy
Tuesday 12 September 2017 by Libadmin2017

References: 17th International Multidisciplinary Scientific GeoConference SGEM 2017, www.sgem.org, SGEM2017 Conference Proceedings, ISBN 978-619-7408-06-5 / ISSN 1314-2704, 29 June - 5 July, 2017, Vol. 17, Issue 41, 589-596 pp, DOI: 10.5593/sgem2017/41/S19.075

ABSTRACT

This investigation is aimed to determine general development patterns of the natural and climatic situations and lakes of the boreal zone in the later and postglacial time in the southeastern periphery of the Fennoscandian crystalline shield since the time of the last deglaciation. The analysis of the subfossil Cladoceran community was carried out on the basis of the 23 samples of Lake Gahkozero’ bottom sediments in the Republic of Karelia. In the subfossil Cladoceran community of the lake 42 taxa have been identified. The species inhabiting the zones of the Palaearctic and Holarctic are predominant in the lake; most of the identified subfossil remains relate to the pelagic species inhabiting the open part of the reservoir. The discovered subfossil remains of the phytophilous species (representatives of the genera Alona, Alonella, Pleuroxus) indicate the presence of the well-developed zone of macrophytes in the lake. The history of the development and the evolution of the lake is traced by the change of the taxonomic composition in the column of the bottom sediments. In the samples there is a dominance of two taxa - Bosmina (Eubosmina) cf. longispina и Chydorus cf. sphaericus, which replace each other during the evolution of the lake. The analysis of the variation in the diversity of the biotic groups is carried out using indices, determining the degree of species richness, diversity, and the dominance of Cladoceran communities. Results of statistical and stratigraphic analyses are presented.

Keywords: subfossil Cladocera, paleoclimate reconstruction, Republic of Karelia, Gahkozero lake