Cryogenesis and soil formation along a bioclimate gradient in Arctic North America
Article first published online: 2 AUG 2008
Copyright 2008 by the American Geophysical Union.
Journal of Geophysical Research: Biogeosciences (2005–2012)
Volume 113, Issue G3, September 2008
How to Cite
2008), Cryogenesis and soil formation along a bioclimate gradient in Arctic North America, J. Geophys. Res., 113, G03S12, doi:10.1029/2008JG000744., , , , , , and (
- Issue published online: 2 AUG 2008
- Article first published online: 2 AUG 2008
- Manuscript Accepted: 15 MAY 2008
- Manuscript Received: 26 APR 2008
- Arctic soils;
- patterned ground;
 In arctic tundra, cryoturbation resulting from frost heave, cracking, and other cryogenic processes produces patterned ground such as nonsorted circles, stripes, nonsorted polygons, and earth hummocks. We studied cryogenic structures and morphological properties of soils associated with patterned-ground features along a bioclimate gradient in Arctic Alaska and Canada from north (subzone A) to south (subzone E). Most of these soils have strongly developed cryogenic features, including warped and broken horizons, and organic matter moved into the upper permafrost. The expression of cryoturbation generally increases with the gradient southward. Soil color reflects the lithology of the soil, weathering, and accumulation of organic matter. The organic horizons form around the circles, and gleyed matrix with redoximorphic features develop in the lower active layers due to saturation above the permafrost. Cryostructure development depends more on hydrology controlled by microtopography than position along the gradient. The cryostructures form due to freeze-thaw cycles and ice lens formation, which include granular, platy, lenticular, reticulate, suspended (ataxitic), ice lens, and ice wedges. On the surface, the density of nonsorted circles reached their maximum in subzones C and D. However, once the vegetation cover was removed, the nonsorted pattern grounds reached their optimum stage and become closed packed in subzone E. Frost heave decreases in the south as the vegetation changes from tussocks to shrub tundra. Cryogenesis is the controlling factor in patterned ground formation resulting in cryoturbated soil profiles, cryostructures, and carbon sequestration in arctic tundra soils.