Fossil chironomids of Lake Temje
Cobertura |
LATITUDE: 62.050000 * LONGITUDE: 129.483300 |
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Data(s) |
25/11/2013
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Resumo |
A 380 cm long sediment core from Lake Temje (central Yakutia, Eastern Siberia) was studied to infer Holocene palaeoenvironmental change in the extreme periglacial setting of eastern Siberia during the last 10,000 years. Data on sediment composition were used to characterize changes in the depositional environment during the ontogenetic development of the Lake Temje. The analysis of fossil chironomid remains and statistical treatment of chironomid data by the application of a newly developed regional Russian transfer functions provided inferences of mean July air temperatures (T_July) and water depths (WD). Reconstructed WDs show minor changes throughout the core and range between 80 and 120 cm. All the fluctuations in reconstructed water depth lie within the mean error of prediction of the inference model (RMSEP = 0.35) so it is not possible to draw conclusions from the reconstructions. A qualitative and quantitative reconstruction of Holocene climate in central Yakutia recognized three stages of palaeoenvironmental changes. The early Holocene between 10 and 8 ka BP was characterized by colder-than-today and moist summer conditions. Cryotextures in the lake sediments document full freezing of the lake water during the winter time. A general warming trend started around 8.0 ka BP in concert with enhanced biological productivity. Reconstructed mean T_July were equal or up to 1.5 °C higher than today between 6.0 ka and 5.0 ka BP. During the entire late Holocene after 4.8 ka BP, reconstructed mean T_July remained below modern value. Limnological conditions did not change significantly. The inference of a mid-Holocene climate optimum supports scenarios of Holocene climatic changes in the subpolar part of eastern Siberia and indicates climate teleconnections to the North Atlantic realm. |
Formato |
application/zip, 2 datasets |
Identificador |
https://doi.pangaea.de/10.1594/PANGAEA.802679 doi:10.1594/PANGAEA.802679 |
Idioma(s) |
en |
Publicador |
PANGAEA |
Direitos |
CC-BY: Creative Commons Attribution 3.0 Unported Access constraints: unrestricted |
Fonte |
Supplement to: Nazarova, Larisa B; Lüpfert, Herman; Subetto, Dmitry A; Pestryakova, Ludmila A; Diekmann, Bernhard (2013): Holocene climate conditions in central Yakutia (Eastern Siberia) inferred from sediment composition and fossil chironomids of Lake Temje. Quaternary International, 290-291, 264-274, doi:10.1016/j.quaint.2012.11.006 |
Palavras-Chave | #Age, 14C calibrated; Age, 14C conventional; Age, dated; Age, dated material; Age, dated standard deviation; Age dated; Age std dev; AWI_PerDyn; Calculated after Shannon (1948); Central Yakutia, Russia; Chironomidae, larvae, head capsules of dry mass; Dated material; Depth; DEPTH, sediment/rock; Diversity; E; Evenness of species; H(S); Head caps dm; Lab no; Lake_Temje; Number of species; Periglacial Dynamics @ AWI; RPC; Russian peat corer; Sample, optional label/labor no; Spec No; using the CalPal Online program (http://www.calpal-online.de, Danzeglocke et al., 2010, accessed on 2011-11-08) |
Tipo |
Dataset |