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Gelisols are known to occur only in Alaska. Most of the soils have a layer of gelic materials that is underlain by permafrost. Permafrost influences pedogenesis through its effect on the downward movement of the soil solution and on the soil forming processes.
Histels are the Gelisols with large amounts of organic carbon. They are in Alaska. The vegetation is mostly mosses, sedges, and shrubs. The soils are used as wildlife habitat.
Orthels are the Gelisols that show little or no evidence of cryoturbation. They occur throughout the Gelisol area in Alaska. The vegetation is mostly lichens, mosses, sedges, shrubs, black spruce, and white spruce. The soils are used mostly as wildlife habitat.
Turbels are the Gelisols show cryoturbation in the form of irregular, broken, or distorted horizon boundaries, involutions, an accumulation of organic matter on top of the permafrost, ice or sand wedges, or oriented rock fragments. They occur throughout the Gelisol area in Alaska. The vegetation is mostly mosses, sedges, shrubs, and black spruce. The soils are used mostly as wildlife habitat. The Cryepts occur on slopes that receive more solar radiation or in areas where fire or land clearing has changed the thermal properties of the soils enough to allow the permafrost to thaw.