Soil‐Geomorphic Relationships in a First‐Order Valley in Central New York

Abstract

AbstractMorphologically the soils in Hemlock Creek watershed are related to geomorphic development since glaciation. Initial drift deposits covering the 75‐ha area in south‐central New York were modified by mass movement (solifluction) and then altered by fluvial aggradation‐degradation under a periglacial environment, and by erosion in more recent times. Eight soil profiles representative of the geomorphic components forming the watershed were evaluated.Fragiochrepts dominate the shoulder, backslope, and upper footslope components. They are also the major soils on congeliturbate terraces and on step‐treads of the upper basin. Fragiaquepts are common on the lower footslope and toeslope components and also occur on portions of the step‐treads of the cirque‐like basin. Fragipans have formed in both glacial till and congeliturbate deposits indicating a pedologic origin. Structural expression and density of the pans increase with a decrease in natural drainage in both deposits. Dystrochrepts are dominant soils on the summit and on the intermediate level fluvial terraces; Entisols occur on the low level alluvial terraces. Pan formation is thought to be precluded by nearness of bedrock (< 1 m) to the surface in the summit area and by matrix textures in the fluvial terraces. Stratigraphic changes that produce distinct discontinuities in fluvial terrace profiles are readily evident. Incipient stratification in congeliturbate deposits appears to affect soil morphology, especially horizon thickness, in these relatively young soils.