Lithological controls on soil properties, Snow Island, Maritime Antarctica

Soil-parent material is a critical controlling factor of soil properties in the Antarctic region due to a limited degree of soil development. However, the degree to which soil-parent material can be considered the major controlling factor in pedogenesis and subsequent soil physical and chemical properties in Antarctica should be better understood to improve soil mapping and interpretations. The present study aims to analyze the soil properties of different lithological groups on the President Head Peninsula on Snow Island, Maritime Antarctica. Thirty soil profiles across the major lithological groupings on Snow Island (beach deposits, andesites, basalts/andesites, conglomerate, sandstones, siltstones, and mudstones) were described, and the morphological, physical, and chemical properties of samples from sampled genetic horizons were characterized. Beach deposits were most clearly differentiated from other lithological groups, whereas most other groups overlapped strongly in observed properties. Whereas some lithological groups (e.g., sedimentary rock groups) were characterized largely by immature soils with little degree of pedogenesis, other sampled soils exhibited more development. The soil-parent material relationships of Snow Island revealed a unique setting of a complex heterogeneous landscape and show that the area has a great pedological complexity induced by phosphatization, melanization, and cryoturbation processes that preclude placing primary importance on parent material and lithology as the major controlling factor in Antarctic soils.