Vegetation and climate history during the last glacial-interglacial cycle at Lake Van, eastern Anatolia

• Main Author: Pickarski, Nadine
• Other Authors: Litt, Thomas, Langer, Martin R.
• Format: Doctoral or Postdoctoral Thesis
• Language: English
• Published: Universitäts- und Landesbibliothek Bonn 2014
• Subjects: ddc:550; North Atlantic
• Online Access: https://hdl.handle.net/20.500.11811/6072

This study investigated the first continuous high-resolution pollen record from Lake Van, eastern Anatolia that encompasses the last glacial-interglacial cycle (~130 ka BP). The reconstructed paleovegetation documents a series of climatic and environmental events and yields information about vegetation succession in the Near East. Palynological analyses were extracted from the lacustrine sedimentary record obtained during the drilling campaign at the ’Ahlat Ridge’ in 2010. Being located in a semi-arid region, the regional environment at Lake Van is characterized by a continental climate. Therefore, the reconstruction of vegetation from the detailed palynological investigations reflects an alternation of an oak-steppe forest and a dwarf-shrub steppe/desert steppe vegetation. In general, cold and arid environmental conditions can be characterized by the dominance of Ephedra, Artemisia , chenopods and grasses, whereas increased temperature and moisture availability suggest more favorable environmental conditions for the expansion of a warm-temperate steppe-forest (e.g. Quercus). These climate cycles were strongly associated with changes in the oceanic and atmospheric circulation of the North Atlantic Ocean. In eastern Anatolia the climate evolution within the last interglacial (~130- 111 ka BP) can be described as a relatively stable warm period with one pronounced short-term climate setback (C 25 cooling event; ~115 ka) towards the end of the last interglacial period. Timing and length of the interglacial conditions are comparable with southern European pollen records. Furthermore, the palynological sequence at Lake Van documents a vegetation succession with several climatic phases: (i) the Pistacia phase and the Quercus-Ulmus phase during the initial warming (130.9- 127.2 ka BP) indicating summer dryness and mild winter conditions; (ii) the Carpinus phase (127.2-124.1 ka BP) suggesting slightly colder temperatures with higher moisture availability; and (iii) the increasing Pinus phase at ~124 ka, which marks the ...