Soil and landform interplay in the dry valley of Edson Hills, Ellsworth Mountains, continental Antarctica

Abstract

The main relief units from the dry valley of Edson Hills, Ellsworth Mountains, Antarctica (79°49′12.4″/83°40′16.1″), were assessed, emphasizing the analysis of soil and landform interplay. Soil morphological, physical, and chemical properties; salinity; surface boulder weathering (frequency and feature); classification; and weathering stages were analyzed. Three distinct landforms summarize the geomorphology of the dry valley of Edson Hills, Ellsworth Mountains: (i) periglacial features like slightly creeping debris-mantled slopes, steep debris-mantled slopes, patterned grounds, and thermokarst; (ii) glacial features like hummocky moraines, lateral moraines (supraglacial), lakes, kettle hole (proglacial), cirques infill (subglacial), horn, and arête (erosional glacial); and (iii) nonglacial features like scree slopes and talus deposits. All these glacial and periglacial features are related to the West Antarctica ice sheet variations. Soils in the dry valley of Edson Hills are pedologically poorly developed. However, the degree of development in soils associated with patterned ground and moraine systems is remarkable. All soils present desert pavement owing to the action of severe aeolian erosion. In addition, soils accumulate salts depending on the local drainage conditions. The most expressive soil classes among the studied soils were Typic Haploturbel and Typic Anhyorthel, especially because of: (i) a general trend of ice-cemented permafrost occurrence in lower portions of the landscape, particularly in the patterned ground area and in the hummocky moraine; and (ii) the presence of dry permafrost in higher positions of the landscape, in relief units such as in debris-mantled slopes and talus deposits. Thus, a close relationship among soil characteristics and landforms were observed in the dry valley of Edson Hills.