Shallow depositional basins as potential archives of palaeoenvironmental changes in southwestern Greenland over the last 800 years
| العنوان: | Shallow depositional basins as potential archives of palaeoenvironmental changes in southwestern Greenland over the last 800 years |
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| المؤلفون: | Jiří Lehejček, Jakub Houška, Daniel Nývlt, Karel Němeček, Daniel Vondrák, Petra Luláková, Václav Tejnecký, Ondřej Drábek, Barbora Chattová, Matěj Roman |
| المصدر: | Boreas. 50:262-278 |
| بيانات النشر: | Wiley, 2020. |
| سنة النشر: | 2020 |
| مصطلحات موضوعية: | 010506 paleontology, Archeology, geography, geography.geographical_feature_category, 010504 meteorology & atmospheric sciences, Geology, Glacier, 15. Life on land, Structural basin, 01 natural sciences, law.invention, Sedimentary depositional environment, Arctic, 13. Climate action, North Atlantic oscillation, law, Physical geography, Radiocarbon dating, Chronostratigraphy, Ecology, Evolution, Behavior and Systematics, Holocene, 0105 earth and related environmental sciences |
| الوصف: | The Arctic, one of the most sensitive components of the Earth's climate system, experienced pronounced climatic fluctuations during the Late Holocene. In order to obtain a detailed record of past environmental and climatic variability, sedimentary cores from two interconnected infilled depositional basins in the Kobbefjord area, southwestern Greenland, were retrieved and subjected to a multi-proxy investigation. The absolute chronostratigraphy was established through radiocarbon (C-14) and short-lived radioisotope (Pb-210, Cs-137) dating. We also analysed magnetic susceptibility, grain size, X-ray fluorescence element composition, total content of carbon, nitrogen and sulphur, biogenic silica and diatom assemblages. The palaeoenvironmental reconstruction presented from the upper basin records similar to 800 years of sedimentation in a former shallow Arctic lake/pond that was modulated by catchment processes and regional hydroclimate. The record is dominated by alternating periods of increased organic and clastic deposition, suggesting warmer/drier and colder/wetter climate, respectively. Comparison of our records with other proxy-based lacustrine, marine and glacier records and instrumental measurements from Greenland and the North Atlantic reveals common climatic trends, consistent with the inferred North Atlantic Oscillation pattern. Periods at similar to 800-600, similar to 320-220 and similar to 140-30 cal. a BP correspond to the main cold phases. The earliest climatic deterioration coincides with the demise of the nearby Norse Western Settlement. The most recent cold period represents the culmination of the Little Ice Age with the maximum Holocene advances of Greenland glaciers. Ameliorated conditions predominated at similar to 550-320 and similar to 220-140 cal. a BP. The evolution of both water bodies is concluded by transition into oligotrophic peat bogs after complete infilling of the basins at similar to 30 cal. a BP. Despite differences in proxy signals between the coring sites, this study endorses the usefulness of shallow lake/pond sediments from infilled basins for environmental reconstructions, as long as local depositional processes do not mask the external driving factors. |
| تدمد: | 1502-3885 0300-9483 |
| URL الوصول: | https://explore.openaire.eu/search/publication?articleId=doi_________::ebc85e89e3e752198b1ab62b01d35b53 https://doi.org/10.1111/bor.12483 |
| حقوق: | CLOSED |
| رقم الأكسشن: | edsair.doi...........ebc85e89e3e752198b1ab62b01d35b53 |
| قاعدة البيانات: | OpenAIRE |
| تدمد: | 15023885 03009483 |
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