Holocene vegetation dynamics and climate change in Kamchatka Peninsula, Russian Far East

We re-examined sixteen pollen records from non-volcanic areas in the Kamchatka Peninsula to reconstruct vegetation and climate changes during the Holocene. Pollen recordswere first summarized and evaluated for each of three main physiographic regions: (1)Western Lowland(WL), open to the Sea of Okhot...

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Bibliographic Details
Published in:Review of Palaeobotany and Palynology
Main Authors: Dirksen, Veronika, Dirksen, Oleg, Diekmann, Bernhard
Format: Article in Journal/Newspaper
Language:unknown
Published: ELSEVIER SCIENCE BV 2013
Subjects:
Online Access:https://epic.awi.de/id/eprint/32022/
https://doi.org/10.1016/j.revpalbo.2012.11.010
https://hdl.handle.net/10013/epic.40688
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Summary:We re-examined sixteen pollen records from non-volcanic areas in the Kamchatka Peninsula to reconstruct vegetation and climate changes during the Holocene. Pollen recordswere first summarized and evaluated for each of three main physiographic regions: (1)Western Lowland(WL), open to the Sea of Okhotsk (6 records); (2) Central Kamchatka Depression (CKD), bordered by mountains (4 records); and (3) Eastern Coast (EC), facing the Pacific Ocean (6 records), and then compared over the peninsula. The synthesized data suggest that the climate over Kamchatka was generally wet and mild before ca. 5.8 ka (1 ka=1000 cal. yrs BP) due to strong and prolonged maritime influence. The first forest maximumin the CKD started at ca. 8.9, indicating awarmer climate; however, forest spread along the both coasts was delayed until ca. 7 ka, suggesting a possible modulation of greater effective moisture on the coastal sites. Thewarmest period at ca. 7–5.8 ka is defined by the evidence of maximal forest extension overall the peninsula. During that time, birch (Betula) prevailed over alder (Alnus) in forest everywhere except in the EC. Since ca. 5.8 ka, divergent vegetation patterns became evident in northern vs. southern and coastal vs. interior sites that correspondwith a shift fromwarmer/maritime climate to cooler/continental climate. Also, greater climate variability accompanied the Neoglacial cooling since 5.8 ka. This climate cooling, indicated by drastic shrub expansion, advanced southward from the northern coasts (ca. 5.8 ka) to the central interior and coastal areas (ca. 5 ka) and then to the south (ca. 3.5 ka). Subsequent warming, suggested by the evidence of a second forest maximum, advanced westward from the EC (ca. 5.2 ka) to the CKD (ca. 3.2 ka) and then to the WL (ca. 1.9 ka). An advance of larch (Larix) in the CKD since ca. 3.2 ka points to increased climate continentality and larger seasonal variations. In contrast, alder forest spread after ca. 1.7 ka, reported only from the southern EC and CKD sites, indicates a mild, ...