A high-quality annually laminated sequence from Lake Belau, Northern Germany: Revised chronology and its implications for palynological and tephrochronological studies

Abstract

The annually laminated record of Lake Belau offers an exceptional opportunity to investigate with high temporal resolution Holocene environmental change, aspects of climate history and human impact on the landscape. A new chronology based on varve counts, 14C-datings and heavy metal history has been established, covering the last 9400 years. Based on multiple varve counting on two core sequences, the easily countable laminated section spans about 7850 varve years (modelled age range c. 9430 to 1630 cal. BP). Not all of the record is of the same quality but approximately 69% of the varves sequence is classified to be of high quality and only c. 5% of low quality. The new chronology suggests dates generally c. 260 years older than previously assumed for the laminated section of the record. The implications for the vegetation and land-use history of the region as well as revised datings for pollen stratigraphical events are discussed. Tephra analysis allowed the identification of several cryptotephra layers. New dates for volcanic eruptions are presented for the Lairg B event ( c. 6848 cal. BP, 2s range 6930–6713 cal. BP), the Hekla 4 event ( c. 4396 cal. BP, 2s range 4417–4266 cal. BP), and Hekla 3 eruption ( c. 3095 cal. BP, 2s range 3120–3068 cal. BP).

Reconstructing Holocene temperature and salinity variations in the western Baltic Sea region: a multi-proxy comparison from the Little Belt (IODP Expedition 347, Site M0059)

“…2), particularly Triticum (wheat) and Secale (rye), are consistently present after ∼ 1100 cal yr BP and increase significantly after ∼ 800 cal yr BP. This signal is also congruent with the Lake Belau record, although the cereal pollen signal at Lake Belau is stronger (Dörfler et al, 2012), probably due to higher agricultural activity close to the lake. The general palynomorph preservation is excellent over the analysed interval, and pollen concentration varies around 500 000 grains per gram sediment for most of the analysed samples.…”

“…Particularly clear signals occurring in both Lake Belau and M0059 pollen records are the arrival of Fagus (beech) in the catchment area ∼ 6000 cal yr BP, a characteristic decline in Ulmus (elm) around ∼ 5600 cal yr BP after preceding values between ∼ 5 and ∼ 10 %, maximum percentages of Alnus (alder) at ∼ 5200 cal yr BP, and maximum percentages of Fagus between ∼ 1800 and ∼ 600 cal yr BP ( Fig. 2 and Dörfler et al, 2012). Grains of cultivated Poaceae taxa, i.e.…”

“…The time interval investigated in this study comprises the transition from freshwater to the brackish-marine conditions of the Littorina Sea stage to the present brackish Baltic Sea. In the Baltic Proper, the Baltic Ice Lake (∼ 16 000 to ∼ 11 700 cal yr BP) was followed by the partly brackish Yoldia Sea stage (∼ 11 700 to ∼ 10 700 cal yr BP), the lacustrine Ancylus Lake stage (∼ 10 700 to 10 200 cal yr BP), a transitional low-salinity phase (∼ 10 200 to ∼ 7400 cal yr BP), and the Littorina stage Andrén et al, 2015a), Lake Belau (Dörfler et al, 2012), and Lake Flarken (Seppä et al, 2005) are indicated. Continuous (surface) and dashed (bottom) lines indicate dominant current directions.…”

“…2) with a pollen record from varved sediments in Lake Belau in northern Germany ( Fig. 1; Dörfler et al, 2012).…”

Laminated lake sediments in northeast Poland: distribution, preconditions for formation and potential for paleoenvironmental investigation

“…Despite numerous studies of lake sediment cores from other Polish lakes, only short laminated sections were occasionally found and are related to early stages of lake development (Więckowski 1978). Recently, an intermittently laminated core was reported from Lake Miłkowskie in the Land of Great Masurian Lakes (Wacnik 2009), and (Petterson 1996, Zillén et al 2003; 2 Finish lakes (Ojala et al 2000); 3 Tougjärv (Veski et al 2004); 4 Loch Ness (Cooper and O'Sullivan 1998); 5 Loe Pool (Simola et al 1981); 6 Lake Diss Mere (Peglar et al 1984); 7 Belauer See (Dörfler et al 2012); 8 Hämelsee (Merkt and Müller 1999); 9 Woseriner See (Dreibrodt et al 2002); 10 Sacrower See (Lüder et al 2006); 11 Lake Goscią _ z (Ralska-Jasiewiczowa et al 1998); 12 Meerfelder Maar (Brauer et al 1999); 13 Holzmaar (Zolitschka et al 2000); 14 Frickenhauser See (Enters et al 2006); 15 Steisslinger See (Eusterhues et al 2002); 16 Ammersee (Czymzik et al 2010); 17 Baldeggersee (Lotter et al 1997); 18 Soppensee (Lotter 1989); 19 Lac Pavin (Stebich et al 2005); 20 Lac Bramant (Guyard et al 2007); 21 Lac D'Annecy (Brauer and Casanova 2001); 22 Seebergsee (Hausmann et al 2002); 23 Silvaplana See (Leemann and Niessen 1994); 24 Mondsee (Wolff et al 2006); 25 Längsee (Schmidt et al 2002); 26 Lake Butrint (Ariztegui et al 2010); 27 Lake Montcortés (Corella et al 2011); 28 Lake La Cruz (Romero-Viana et al 2008); 29 Lake Zoñar (Martín-Puertas et al 2009) conditions for deposition of laminated sediments in meromictic Lake Suminko in the Kashubian Lakeland were investigated by Tylmann et al (2012).…”