We seek to catalog, understand, and quantify the variability in permafrost-affected soils, with focus on Alaska.
PERMAFROST-AFFECTED SOIL DYNAMICS AND RESPONSE TO ENVIRONMENTAL CHANGE
Comparative Analysis of Soil Properties and Carbon Stocks in Fire- and Permafrost-Affected Soils Under Black Spruce (Copper River Basin, AK)
We investigated differences in forest structure, organic layer thickness, soil organic carbon, and permafrost depth between late successional and post fire (90 to 120 years since burn) plots under black spruce (Picea mariana) in the Copper River Basin, Alaska. Soil properties on post fire plots appear to be on a trajectory of recovery towards late-successional plots with respect to SOC stocks, permafrost depth, and organic layer composition, but remain different despite nearly 100 years since fire disturbance and are therefore potentially sensitive to changes in future fire frequency or climate. Manuscript in peer-review.
Estimates of 21st Century Gelisol Taxonomic Change
Rapid environmental change in Alaska is projected to significantly decrease near-surface permafrost distribution across the state in the next century. Under current rules for soil taxonomy (Soil Survey Staff, 2014), Gelisols (permafrost-affected soils) must have permafrost within 1m or 2m of the soil surface. There- fore, near-surface permafrost change has the potential to have a large impact on Gelisol distribution. The objective of this work was to provide an estimate of potential changes in Gelisol distribution due to near surface permafrost change under the A1B emissions scenario. Manuscript in peer-review.
Dynamics of Non-Sorted Circles
The empirical quantification of rates of material movement in cryoturbated soils has lagged behind the physical and chemical characterization of these materials. We applied a novel suite of elemental (C, Hg), stable isotope (13C) and radioisotope (137Cs, 210Pb, 14C, 10Be) tracers in conjunction with analytical and numerical models to constrain the rates and patterns of soil movement due to cryoturbation in a non-sorted circle (NSC) near Abisko, Sweden.
IMPROVING KNOWLEDGE OF THE SPATIAL DISTRIBUTION OF PERMAFROST-AFFECTED SOILS
Constructing Multi-Modal Cost Rasters For Soil Survey in Remote Regions
Remote region access for soil survey often involves multiple modes of transportation. We are developing methodologies for constructing synthesized cost rasters for use in constrained Latin Hypercube Sampling (cLHS) algorithms, using the Yukon-Kuskokwim Delta region as a case study.
Soils in the Central Brooks Range, AK
Soil profiles were described across a transect in the Midas Lake region of the Central Brooks Range of Alaska and associated field data were aggregated and generalized to reveal major trends and relationships in horizonation between cryoturbated and noncryoturbated soils on the transect. A conceptual model for the geomorphic relationships of cryoturbated and noncryoturbated soils on this landscape was developed.
REDUCING UNCERTAINTIES IN ORGANIC CARBON STOCKS IN PERMAFROST-AFFECTED SOILS
Soil Morphology and Toposequence Complexity in the Alaskan Arctic Foothills
Quantitative data across soil toposequences in the continuous permafrost zone remain limited. Recent modeling studies have shown high uncertainties in lower hillslope SOC stocks in the continuous permafrost zone. For the state of Alaska, the uncertainty in SOC mass in these regions is greater than 200% of current statewide SOC estimates (Shelef et al., 2017). Hence, there is a need for expanded focus on the spatial pattern of soil morphology and soil classification along hillslopes, and major opportunities to bridge the gap from hillslope to landscape scales.
Soil Carbon Stocks Under Late-Successional Black Spruce in the Copper River Basin, AK
Soils under late-successional forests therefore provide foundational information regarding the potential recovery of soil and permafrost characteristics following disturbance by fire. Twenty-two permafrost-affected soils (predominantly Histoturbels with minor components of Sapristels and Aquiturbels) were investigated under late-suc- cessional black spruce in the Copper River Basin, which contains the largest expanse of glaciolacustrine sediments in Alaska.
Digital Workflow For Generating 2-Dimensional Representations of Cryoturbated Soils
The conceptual framework for dealing with 2-dimensional representations of soil profiles must include the ability to deal with multiple sampled components within individual horizons, which is common in data derived from cryoturbated soils. These tools will be increasingly important in mining and utilizing data for future digital soil mapping initiatives, and perhaps most importantly will allow for the harmonization of disparate data sources and data formats without information loss.