Paleolimnological reconstructions of Holocene environments and climate from Lake Lyadhej-To, Ural Mountains, northern Russia

• Main Authors: Cremer, Holger, Andreev, Andrei, Hubberten, Hans-Wolfgang, Wischer, Frank
• Format: Article in Journal/Newspaper
• Language: English
• Published: INSTAAR, Institute of Arctic and Alpine Research 2004
• Subjects: Antarctic and Alpine Research; Arctic; ural mountains
• Online Access: https://oceanrep.geomar.de/id/eprint/27080/; https://oceanrep.geomar.de/id/eprint/27080/1/2004_Cremer-etal-Paleolimnological_AAARes-36.pdf; https://doi.org/10.1657/1523-0430(2004)036[0147:PROHEA]2.0.CO;2

A sediment core recovered in Lake Lyadhej-To at the northwestern edge of the Ural Mountains reflects the complete Holocene environmental history from ∼11,000 cal. yr B.P. Five limnological episodes are identified in the diatom and geochemical records. The initial lake stage, Episode I (∼11,000–10,850 cal. yr B.P.) is characterized by the absence of biogenic production and a high influx of clastic sediments. Episode II (∼10,850–8650 cal. yr B.P.) is characterized by ice-free conditions during summer, highest bioproductivity, strong growth of planktic diatoms and anoxic bottom waters. This period represents the Holocene climatic optimum. Deterioration of climatic conditions commenced in Episode III (∼8650–7000 cal. yr B.P.) as indicated by distinctly lower bioproductivity and longer persistence of winter ice on the lake. During Episode IV (∼7000–2500 cal. yr B.P.), the diatom and pollen records indicate that temperatures were cool and the growing season was short. Finally, in Episode V (∼2500 cal. yr B.P. to present), limnological conditions, indicated by increased organic carbon and diatom deposition, initially suggest improved conditions followed by a return to modern conditions beginning ∼500 cal. yr B.P. The pollen stratigraphy from Lake Lyadhej-To is consistent with other paleoclimatic records from northern Eurasia, confirming rapid postglacial warming, the presence of dense tree forests during the climatic optimum, and finally a gradual southward retreat of the treeline towards its modern location.