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The quantity and preservation of carbon-rich organic matter (OM) underlying permafrost uplands, and the evolution of carbon accumulation with millennial climate change, are large sources of uncertainty in carbon cycle feedbacks on climate change. We investigated permafrost OM accumulation and degradation over the Holocene using a transect of sediment cores dating back to at least c. 6-8 ka, from a hillslope in the Eight Mile Lake watershed, central Alaska. This dataset collected from four permafrost sediment cores includes a variety of biogeochemical datasets including radiocarbon, carbon, nitrogen, particle size, amino acids (concentrations and D:L), bulk density and water content.
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15,700 year sediment record of productivity, carbon accumulation and environmental change at Eight Mile Lake, central Alaska; 2020-2023
The role of high latitude lakes in storing and processing terrestrial organic carbon export is not well understood. We analyzed a 2.7-meter (m) -long sedimentary record from Eight Mile Lake that extends back 15,700 years to evaluate connections between productivity, organic carbon accumulation and late Quaternary environmental change in central Alaska. We analyzed macrofossil radiocarbon, alongside physical and biogeochemical properties. This dataset includes data from 12 sediment cores collected across Eight Mile Lake. These cores span time frames of 1000 - 15,700 years. This dataset includes bulk physical data, organic matter abundance, biogenic silica abundance, particle size, geochronological information, magnetic susceptibility data and hyperspectral imagery.
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- PAR ID:
- 10506808
- Publisher / Repository:
- NSF Arctic Data Center
- Date Published:
- Subject(s) / Keyword(s):
- Alaska Arctic Organic Matter Carbon Holocene Lake Sediment Permafrost Paleolimnology BNZ LTER
- Format(s):
- Medium: X
- Location:
- central Alaska
- Sponsoring Org:
- National Science Foundation
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