SOIL GEOMORPHOLOGY ON BEDROCK AND COLLUVIAL TERRAIN WITH PERMAFROST IN CENTRAL ALASKA, USA

The depth to permafrost, thickness of the surface organic layer, and s trength of redoximorphic features are closely correlated in soils on l ow-relief bedrock hills and colluvial slopes near Hughes, Alaska. Soil s can be arrayed along a morphological gradient from warm-dry-mineral to cold-wet-organic, and the ranks of soils along this gradient correl ate with topographic parameters and mineral soil texture. The warm-dry -mineral soils tend to occur on coarse-textured materials, convex slop es, steep slopes, and south-facing slope aspects, while the cold-wet-o rganic soils tend to occur on fine-textured materials, concave slopes, gentle slopes, and north-facing aspects. Slope shape and mineral soil texture are the geomorphic factors most closely associated with the r anking of soils along the morphological gradient from warm-dry-mineral to cold-wet-organic.