A lake-bog succession vs. climate changes from 13,300 to 5900 cal. BP in NE Poland in the light of palaeobotanical and geochemical proxies Monika Karpińska-Kołaczek a,b,e, ⁎, Renata Stachowicz-Rybka c , Andrzej Obidowicz c , Michał Woszczyk d , Piotr Kołaczek a a Department of Biogeography and Palaeoecology, Faculty of Geographical and Geological Sciences, Adam Mickiewicz University, Dzięgielowa 27, 61-680 Poznań, Poland b Laboratory of Wetland Ecology and Monitoring, Faculty of Geographical and Geological Sciences, Adam Mickiewicz University, Dzięgielowa 27, 61-680 Poznań, Poland c W. Szafer Institute of Botany, Polish Academy of Sciences, Lubicz 46, 31-512 Kraków, Poland d Department of Quaternary Geology and Paleogeography, Faculty of Geographical and Geological Sciences, Adam Mickiewicz University, Dzięgielowa 27, 61-680 Poznań, Poland e Department of Palaeobotany and Palaeoherbarium, Faculty of Biology and Earth Sciences, Jagiellonian University, Lubicz 46, 31-512 Kraków, Poland abstract article info Article history: Received 18 January 2016 Accepted 4 June 2016 Available online 13 June 2016 This paper presents and discusses the influence of climatic and edaphic factors on vegetation succession of the postglacial Lake Czarne (LC) located in NE Poland. On the basis of pollen, macroscopic plant remains, non- pollen palynomorphs (NPPs), and geochemical analyses, we reconstructed the transition from a clear oligotro- phic lake to an ombrotrophic mire from 13,300 to 5900 cal. BP. Climatic events/periods that may have affected the lake/mire succession were as follows: (i) relatively warm conditions in the younger part of the Younger Dryas (ca. 12,220 cal. BP) that led to water eutrophication recorded as blooms of Scenedesmus ellipticus, whose response preceded that of woodland vegetation by ca. 200 years, (ii) the warming of the Late Glacial–Holocene transition and early Holocene that caused the final melting of dead ice block(s) and led to the deepening of the water body and/or an increase in the water level, the retreat of submerged macrophytes, and the enrichment of waters with sulphur, (iii) the global cold period between 8600 and 8000 cal. BP that contributed to a rise in the water level during the phase of sedge swamp and enabled the reappearance of Nymphaeaceae and blooms of S. ellipticus (ca. 8570–8500 cal. BP), and (iv) the global climate cooling 6500–5900 cal. BP that still remains enigmatic in terms of palaeobotanical patterns; however, geochemical markers point to an increase in the water level and enhanced erosion in the LC catchment ca. 6200–6000 cal. BP. Lake terrestrialization resulted in the concurrent appearance of microhabitats suitable for mosses with contrasting ecological preferences, e.g., Warnstorfia exannulata (acidic) and Scorpidium revolvens (alkaline), or Straminergon stramineum (acidic), Meesia triquetra (alkaline) and S. revolvens (alkaline). © 2016 Elsevier B.V. All rights reserved. Keywords: Pollen Non-pollen palynomorphs Plant macrofossils Younger Dryas Early Holocene Central Europe 1. Introduction The area surrounding the Baltic Sea is characterized by a great number of lakes, most of which developed after the retreat of the Scan- dinavian Ice Sheet (Bjӧrk, 2010). At that time, many basins were filled with water originating from the melting of dead ice blocks and degrada- tion of permafrost (e.g., Błaszkiewicz, 2011; Błaszkiewicz et al., 2015; Lauterbach et al., 2011; Michczyńska et al., 2013). Subsequently, the newly formed lakes underwent processes of natural succession, but their patterns, as well as timing, were different throughout that area (e.g., Ralska-Jasiewiczowa and Starkel, 1988; Latałowa et al., 2004). Climate is among the most important factors influencing ecological succession in postglacial lakes (Birks and Birks, 2008; Zawiska et al., 2015), and the period outlined by this article (13,300–5900 cal. BP) was characterized by its high variability. The climatic fluctuations were connected with the final stage of warm GI-1 interstadial and early Holocene alternating with cold events such as the Younger Dryas (GS-1 stage), which preceded the Holocene and two well-recognized intra-Holocene coolings, the “Preboreal oscillation” (PBO; Bjӧrck et al., 1997) and the “8.2 ka BP” event (Alley et al., 1997), being manifestations of global cold periods (Wanner et al., 2011). Moreover, another period of global cooling was recorded between 6500 and 5900 cal. BP (Wanner et al., 2011). It took place within the Holocene Thermal Maximum in the Baltic region that lasted from at least 7500 to 5000 cal. BP (Seppä and Poska, 2004; Seppä et al., 2005; Heikkilä and Seppä, 2010; Latałowa et al., 2013). Hence, the signal of this cooling might have been masked by a general warming trend. These cold phases influenced plant succession in lakes and rate of terrestrialization in Review of Palaeobotany and Palynology 233 (2016) 199–215 ⁎ Corresponding author at: Department of Biogeography and Palaeoecology, Faculty of Geographical and Geological Sciences, Adam Mickiewicz University, Dzięgielowa 27, 61- 680 Poznań, Poland. E-mail address: monika_kk@interia.eu (M. Karpińska-Kołaczek). http://dx.doi.org/10.1016/j.revpalbo.2016.06.001 0034-6667/© 2016 Elsevier B.V. All rights reserved. Contents lists available at ScienceDirect Review of Palaeobotany and Palynology journal homepage: www.elsevier.com/locate/revpalbo