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Filters: Tags: Thermokarst (X) > partyWithName: U.S. Geological Survey - ScienceBase (X)

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This dataset supports a published study on the effects of permafrost thaw on greenhouse gas fluxes and microbial activities at the Alaska Peatland Experiment (APEX), part of the Bonanza Creek LTER, in interior Alaska. The dataset includes autochamber CO2 and CH4 fluxes, net ecosystem exchange, ecosystem respiration, soil temperatures, climate data, microbial qPCR data, soil physical chemistry, soil extract chemistry, and rates of microbial activities, both from lab incubations, and rates derived from an isotope based process model.
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The current state of permafrost in Alaska and meaningful expectations for its future evolution are informed by long-term perspectives on previous permafrost degradation. Thermokarst processes in permafrost landscapes often lead to widespread lake formation and the spatial and temporal evolution of thermokarst lake landscapes reflects the combined effects of climate, ground conditions, vegetation, and fire. This study provides detailed analyses of thermokarst lake sediments of Holocene age from the southern loess uplands of the Yukon Flats; including bathymetry and sediment core analyses across a water depth transect. The sediment core results, dated by radiocarbon and 210Pb, indicate the onset of finely laminated...
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During recent decades, lake levels in the Yukon Flats region of interior Alaska have fluctuated dramatically. However, prior to recorded observations, no data are available to indicate if similar or more extreme variations occurred during past centuries and millennia. This study explores the history of Yukon Flats lake origins and lake levels for the past approximately 5,500 years from sediment analyses guided by previous work on permafrost extent, thermokarst, and modern isotope hydrology. Sediments dated by 210Pb and AMS radiocarbon indicate stable chronologies following initial lake initiation. Subsequent lithology is autochthonous, and oxygen isotope ratios of endogenic carbonate reflect lake level change at...
    map background search result map search result map Data release for Lake levels in a discontinuous permafrost landscape: Late Holocene variations inferred from sediment oxygen isotopes, Yukon Flats, Alaska Data Release for "Holocene thermokarst lake dynamics in northern Interior Alaska: the interplay of climate, fire, and subsurface hydrology" Flux and Soil Data from the Alaska Peatland Experiment 2014 to 2016 Data release for Lake levels in a discontinuous permafrost landscape: Late Holocene variations inferred from sediment oxygen isotopes, Yukon Flats, Alaska Flux and Soil Data from the Alaska Peatland Experiment 2014 to 2016 Data Release for "Holocene thermokarst lake dynamics in northern Interior Alaska: the interplay of climate, fire, and subsurface hydrology"