Figure 2 | Scientific Reports

Figure 2

From: Alteration of rocks by endolithic organisms is one of the pathways for the beginning of soils on Earth

Figure 2

Soil-like eluvial-illuvial differentiation in cryptoendolithic system (Thala Hills, East Antarctica, gneiss): (a) – vertical stratification in endolithic system, the sequence of horizons resembles the profile of Podzol, for convenience the indexes of horizons are given by the analogy with the ones in Podzols; (b) – vertical distribution of C, Si, Al, Fe according to SEM-EDX elemental analyses in thin section from the endolithic system; (c) – silica glaze and varnish on the day surface of the gneiss rock; (d) – the upper Bs horizon (sesquioxides accumulation) with iron rich coatings; (e,g) – endolithic organogenous horizon A dominated by fungi with weathering patterns associated with melanin and hyaline pigmented fungal hyphae; (f,h)– bleached eluvial horizon E, clean surfaces without organo-mineral coatings and mineral degradation patterns; (i) – endolithic organogenous horizon dominated by cyanobacteria biofilms; (j) – rather clean mineral surfaces in the parent rock without distinct biofilms; (k) – the lower Bhs horizon (organic matter and sesquioxides accumulation) with carbon and iron rich coatings. Images (ck) made by SEM in secondary electrons mode. Fungi and cyanobacteria dominated horizons may be linked by the mutualistic relationships of inhabiting organisms, endolithic (proto)lichen formation is not excluded.

Back to article page