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Titel |
Vegetation history of central Chukotka deduced from permafrost paleoenvironmental records of the El'gygytgyn Impact Crater |
VerfasserIn |
A. A. Andreev, E. Morozova, G. Fedorov, L. Schirrmeister, A. A. Bobrov, F. Kienast, G. Schwamborn |
Medientyp |
Artikel
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Sprache |
Englisch
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ISSN |
1814-9324
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Digitales Dokument |
URL |
Erschienen |
In: Climate of the Past ; 8, no. 4 ; Nr. 8, no. 4 (2012-08-17), S.1287-1300 |
Datensatznummer |
250005712
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Publikation (Nr.) |
copernicus.org/cp-8-1287-2012.pdf |
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Zusammenfassung |
Frozen sediments from three cores bored in the permafrost
surrounding the El'gygytgyn Impact Crater Lake have been studied for
pollen, non-pollen palynomorphs, plant macrofossils and rhizopods. The
palynological study of these cores contributes to a higher resolution of
time intervals presented in a poor temporal resolution in the lacustrine
sediments; namely the Allerød and succeeding periods. Moreover, the
permafrost records better reflect local environmental changes, allowing a
more reliable reconstruction of the local paleoenvironments. The new data
confirm that shrub tundra with dwarf birch, shrub alder and willow dominated
the lake surroundings during the Allerød warming. Younger Dryas pollen
assemblages reflect abrupt changes to grass-sedge-herb dominated
environments reflecting significantly drier and cooler climate. Low shrub
tundra with dwarf birch and willow dominate the lake vicinity at the onset
of the Holocene. The find of larch seeds indicate its local presence around
11 000 cal yr BP and, thus a northward shift of treeline by about 100 km
during the early Holocene thermal optimum. Forest tundra with larch and
shrub alder stands grew in the area during the early Holocene. After
ca. 3500 cal yr BP similar-to-modern plant communities became common in the
lake vicinity. |
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