Soils of the Argentine Antarctica

Abstract

Antarctic soils have been studied since the mid-twentieth century. The first studies were focused on the intense influence of seabirds in soil genesis, specially through the microbiological decomposition of guano, while other important pedogenetic processes were less studied. Sub- sequent studies showed that climate, vegetation and micro-organisms were also key factors in the formation of these soils. Significant differences were found in soil genesis in the different sites studied, which allowed to recognize the current pedogenetic processes and those developed under warmer climates. In the present chapter, we present a review of the edaphic studies carried out in the Argentine Antarctic. They were focused in the ice-free areas of the northern sector of the Antarctic Peninsula and the surrounding islands: Marambio Island (Trinidad Peninsula), Esperanza Bay (Tabarín Peninsula), Potter Peninsula (25 de Mayo Island), Harmony Point (Nelson Island), Cape Spring, Leopard and Penguin Islands (Coast of Danco). A complex landscape, involving soils with different properties, evolved mainly through the partici- pation of the five soil-forming factors. The presence of permafrost, key to soil classification, was observed mainly in the Eastern sector of the northern Antarctic Peninsula. In the Western sector, the melting of the soils in the summer allowed the development of the horizons used for the description. The diagnostic features used were the presence of ochric, mollic, histic, cryoturbation, permafrost and glacic layers and the presence of gelic materials. Soils correspond to the orders Gelisols, Mol- lisols, Inceptisols, Histosols, Spodosols and Entisols.