Radiocarbon dates, porewater hydrochemistry, calcareous microfossils and pollen data from a lake sediment core (PG1967) from Herschel Island (Yukon, Canada) ...
Thermokarst lakes cover nearly one fourth of ice-rich permafrost lowlands in the Arctic. Sediments from an athalassic subsaline thermokarst lake on Herschel Island (69°36'N; 139°04'W, Canadian Arctic) were used to understand regional changes in climate and in sediment transport, hydrology,...
Main Authors: | , , , , , , , , |
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Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
PANGAEA
2018
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Subjects: | |
Online Access: | https://dx.doi.org/10.1594/pangaea.886875 https://doi.pangaea.de/10.1594/PANGAEA.886875 |
Summary: | Thermokarst lakes cover nearly one fourth of ice-rich permafrost lowlands in the Arctic. Sediments from an athalassic subsaline thermokarst lake on Herschel Island (69°36'N; 139°04'W, Canadian Arctic) were used to understand regional changes in climate and in sediment transport, hydrology, nutrient availability and permafrost disturbance. The sediment record spans the last ~11,700 years and the basal date is in good agreement with the Holocene onset of thermokarst initiation in the region. Electrical conductivity in pore water continuously decreases, thus indicating desalinization and continuous increase of lake size and water level. The inc/coh ratio of XRF scans provides a high-resolution organic-carbon proxy which correlates with TOC measurements. XRF-derived Mn/Fe ratios indicate aerobic versus anaerobic conditions which moderate the preservation potential of organic matter in lake sediments. The coexistence of marine, brackish and freshwater ostracods and foraminifera is explained by (1) oligohaline to ... : Supplement to: Fritz, Michael; Unkel, Ingmar; Lenz, Josefine; Gajewski, Konrad; Frenzel, Peter; Paquette, Nathalie; Lantuit, Hugues; Körte, Lisa; Wetterich, Sebastian (2018): Regional environmental change versus local signal preservation in Holocene thermokarst lake sediments: A case study from Herschel Island, Yukon (Canada). Journal of Paleolimnology, 60(1), 77-96 ... |
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