Subaerial endolithic systems of the current extreme environments on Earth provide exclusive insight into emergence and development of soils in the Precambrian when due to various stresses on the surfaces of hard rocks the cryptic niches inside them were much more plausible habitats for organisms than epilithic ones. Using an actualistic approach we demonstrate that transformation of silicate rocks by endolithic organisms is one of the possible pathways for the beginning of soils on Earth. This process led to the formation of soil-like bodies on rocks in situ and contributed to the raise of complexity in subaerial geosystems. Endolithic systems of East Antarctica lack the noise from vascular plants and are among the best available natural models to explore organo-mineral interactions of a very old “phylogenetic age” (cyanobacteria-to-mineral, fungi-to-mineral, lichen-to-mineral). On the basis of our case study from East Antarctica we demonstrate that relatively simple endolithic systems of microbial and/or cryptogamic origin that exist and replicate on Earth over geological time scales employ the principles of organic matter stabilization strikingly similar to those known for modern full-scale soils of various climates.

This paper brings together topographic cross-section ‘windows’ from across Antarctica to illustrate soil–landscapes from the margins of the polar plateau in the Transantarctic Mountains and McMurdo Dry Valleys, through East Antarctic coastal areas, to the northern Antarctic Peninsula Region. Soils identified range from Gelisols in the Ross Sea Region, through Gelisols and Entisols in coastal East Antarctica, to a mixture of Gelisols, Entisols, Spodosols and Inceptisols in the northern Antarctic Peninsula Region where permafrost is not ubiquitous. The relative impacts of the soil-forming factors are considered. At a continental scale climate is the main driver of the differences observed between soils in different areas. At local scales strong soil–topographic relationships are observed. Organisms, time and parent material are dominant influences on soil properties only in relatively localized situations. Organisms dominate in areas of organic matter or guano accumulation and time is a dominant influence on exceptionally old upland surfaces in the McMurdo Dry Valleys. The US Department of Agriculture’s Soil Taxonomy gives a useful overall appraisal of Antarctic soils; however, for detailed work, there is a need to introduce some new categories at subgroup level to better capture the range of soils described.

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This article discusses radiocarbon dating results for soils and soil-like systems in the East Antarctic oases, including Schirmacher, Thala Hills, and Larsemann Hills. The organic matter of endolithic and hypolithic systems, soils of wind shelters, and soils under moss-algae vegetation were dated along with micro- and macroprofiles. Organic matter pools formed under extreme climatic conditions and originated not from vascular plants but from cryptogamic organisms, and photoautotrophic microbes have been identified within the oases of the East Antarctica. The organic matter of the most of East Antarctic soils is young and cannot reach a steady state because of the high dynamism in the soil cover due to active erosion. The oldest soil organic matter in East Antarctica was found in the soils formed in wind shelters and endolithic soil-like systems under the protection of consolidated rock surfaces. According to our data, the maximal duration for the formation of organic matter profiles within the oases of East Antarctica is ~500 yr, which is similar to the age determined for High Arctic soils in Eurasia. The absence of older soils, comparable with the Holocene deglaciation, can be due to the extreme conditions resulting in occasional catastrophic events that destroyed the soil organic horizons.

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