Contents lists available at ScienceDirect Quaternary International journal homepage: www.elsevier.com/locate/quaint Holocene sedimentation in the central part of Lake Ladoga Tatyana Sapelko a,* , Shamil Pozdnyakov a , Denis Kuznetsov a , Anna Ludikova a , Ekaterina Ivanova a , Maria Guseva a , Elya Zazovskaya b a Institute of Limnology, Russian Academy of Science, St.Petersburg, Russia b Institute of Geography, Russian Academy of Science, Moscow, Russia ARTICLE INFO Keywords: Lake Ladoga Paleolimnology Sedimentation rates Holocene Climate Paleoenvironmental changes ABSTRACT New multi-proxy paleolimnological study of the sediment sequence from the central part of Lake Ladoga enabled not only reconstructing the dynamics of the Holocene paleoenvironments, but also tracing changes in the lake ecosystem productive, sedimentation conditions and sedimentation rate. The analyses included lithology, loss- on-ignition, metals, grain-size distributions, including fractions of < 1 μ, pollen and diatoms. A series of radiocarbon (AMS) data was also obtained. The earlier period (prior to 9000 cal. BP) is characterized with the lowest organic matter content and highest proportion of the fine sedimentary fraction (including that of < 1 μ). The transition from periglacial to forest vegetation, climate warming, and the lake level drop are inferred. In the next period (9000-4700 cal. BP) warmest climate resulted in vegetation changes, increased productivity of the Lake Ladoga ecosystem as inferred from increasing siliceous microalgae concentration and organic matter content. In the late period (4700-1000 cal. BP) climate deterioration resulted in vegetation changes. However the lake ecosystem remained highly productive as inferred from high diatom concentrations. 1. Introduction Lake Ladoga is one of the fifteen largest freshwater lakes in the world and the largest lake in Europe. The area of the lake including islands is 18329 km 2 , with a long-term average level of 5 a.s.l. Its maximum length is 219 km, and its maximum width is 125 km. m. The catchment area of the lake is 258600 km 2 . The average depth of Lake Ladoga is 48.3 m, while its maximum depth is 230 m. The southern part of Lake Ladoga is rather shallow, with an average depth of 15 m, while its northern part is deeper, with an average depth of 82 m. The total water exchange time is 11 years and the conditional water exchange coefficient is 0.088 (Naumenko, 1995). The lake basin is located at the junction of the Baltic Crystalline Shield and the Russian Platform. The lake has complex bottom topography with the large number of islands, and the alternation of depressions, sometimes exceeding 100 m depth, with shallow water areas. The Lake Ladoga depression was formed by tectonics in the pre-Quaternary times, and was subsequently affected by the glacial erosion during the Quaternary glaciations. The climate of the Lake Ladoga region is transitional from the marine climate of temperate latitudes to continental one and is characterized by significant fluc- tuations in air temperature, high relative humidity, high cloud amount and high precipitation level. Lake Ladoga is located on the border of middle and southern taiga. The sediments accumulated in the lake bottom throughout its entire history are the result of the complex processes of transformation of matter in the lake catchment and in the lake itself. The mineral and chemical composition of lake sediments is determined by the specifics of the catchment area (i.e., bedrocks, landscapes, and vegetation), lake basin (its age and morphometry), and biological processes in the water column and at the lake bottom. The spatial distribution of various types of sediments along the lake bottom results from of a complex interaction of hydrophysical, hydrochemical and hydrobiological processes in a water-body, as well as the human impact both on the lake itself and within the entire catchment area. The first information about the evolution of Lake Ladoga dates back to the end of the 18th – 19th centuries, and was based on the studies of coastal sediment sections (Ozeretskovskiy, 1792). First studies of the peat bogs on the southern shore were conducted (Miklouho-Maklay, 1897). At the end of the 19th century, the pioneer studies of the sedi- ments in the bottom of Lake Ladoga were carried out by A.P. Andreev (1877). The sediment samples were analyzed for grain-size distribution, mineral composition and organic matter content, which resulted in the first lake sediments map. Drilling of the lake sediments was first per- formed at the beginning of the 20th century near the Cape of Osinovets (Erassi, 1910). In 1934, Mikulino (Eemian) interglacial clays, glacio- lacustrine varved clays and postglacial deposits were described in a series of 40-m long sediment cores retrieved from this area (Krasnov https://doi.org/10.1016/j.quaint.2019.05.028 Received 31 December 2018; Received in revised form 20 May 2019; Accepted 21 May 2019 * Corresponding author. E-mail address: tsapelko@mail.ru (T. Sapelko). Quaternary International xxx (xxxx) xxx–xxx 1040-6182/ © 2019 Elsevier Ltd and INQUA. All rights reserved. Please cite this article as: Tatyana Sapelko, et al., Quaternary International, https://doi.org/10.1016/j.quaint.2019.05.028