THE RELATIONSHIP OF PATTERN AND GRADIENT OF SLOPES TO SOIL TYPE

Abstract

Three glacial landforms (hummocky moraine, linear disintegration ridge, and washboard ridge) resulting from ice disintegration were studied to determine the relationship of the type of landform to the distribution of soil members or series. A close relationship was observed between a soil member and the nature of the slope segment on which it occurred. Calcareous Dark Brown soils were observed on the uppermost convex portion of the slope on gradients usually greater than 8%; Orthic Dark Brown soils on simple intermediate slopes or 5–8% gradient; Eluviated Dark Brown soils on slightly concave footslopes of 1–3% gradient; Rego Dark Brown wherever 3–5% slopes extended from the margin of depressions; and Gleysolic soils in the concave depressions. The extent of the soil members was found to be a function of the extent of the individual slope segment present in the landform. Orthic Dark Brown soils predominated, to approximately the same extent, on all landforms. Gleysolic soils were extensive in hummocky moraines whereas Eluviated and Calcareous Dark Brown soils were more extensive on ridged landforms, particularly on linear disintegration ridges. Rego Dark Brown soils were most extensive on washboard ridges.