Abstract
The 4.5 m thick Haljala sequence in North Estonia was studied to provide information on palaeoenvironmental changes between 13 800 and 11 300 cal yr BP. Late glacial environmental history of North Estonia was reconstructed using AMS-dated pollen record, sediment composition, plant macrofossils, and ostracods. The obtained data show environmental fluctuations that are linked to the climate shifts of the Last Termination in the North Atlantic region. Decrease in the arboreal pollen accumulation rate around 13 700-13 600 and 13 300-13 100 cal yr BP refers to short deterioration of climate within the Allerod Interstadial and has been correlated with the cooling of the Greenland Interstadial GI-1c and GI-1b events, respectively. Between 13 100 and 12 850 cal yr BP the pollen accumulation rate of trees, shrubs, and herb as well as organic matter increased, indicating short-term climate amelioration and establishment of pine-birch woods. This change has been correlated with the GI-1a event. Climate deterioration during the Younger Dryas (GS-1) was inferred from the reduction of tree pollen and flourishing of cold-tolerant species, such as Artemisia, Chenopodiaceae, and Cyperaceae. New data show that ice cover of the Pandivere Upland started to perish already about 13 800 cal yr BP.
Highlights
The Pandivere ice-marginal formations were shaped by the ice streams of the retreating Scandinavian ice sheet
The proglacial lake systems that developed in front of the decaying ice margin, their formation and configuration were controlled by geology, local topography, and dynamics of the ice sheet as well as climatic fluctuations
The new evidence from Haljala suggests that the area started to deglaciate about 13 800 cal yr BP, about 500 years earlier than previously thought (Vassiljev et al 2005; Saarse et al 2007)
Summary
The Pandivere ice-marginal formations were shaped by the ice streams of the retreating Scandinavian ice sheet. The late glacial history of Estonia has been investigated for a long time, yet any palaeogeographical and palaeoenvironmental reconstructions of the area at the closing stage of the last glaciation have been hampered due to lack of chronology. To fill this gap, we revisited the Haljala site and performed multi-proxy studies of sediment cores. The pollen diagrams by Pirrus (Männil & Pirrus 1963; Pirrus 1965; Pirrus & Sarv 1968) provided a general picture on the vegetation succession and climatic history during the late glacial. The palynological data suffered from simplified taxonomic composition (mostly tree pollen accounts were included), sparse resolution between pollen samples, limited pollen sums, absence of pollen concentration data, and, most importantly, lack of radiocarbon dates, which hindered detailed correlation of the environmental changes
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
