Desert rocks

Silicon dioxide occurs almost everywhere on earth. It is one of the most important and abundant oxides on earth, constituting about 60% weight of the earth s crust as sdica itself or in combination with other metal oxides in sihcates. It commonly is found as sand in the vast ocean and river shores, their beds, deserts, rocks, and minerals. 

Grote, G. Krumbein, W. E. (1992). Microbial precipitation of manganese by bacteria and fungi from desert rock and rock varnish. Geomicrobiology Journal, 10, 49-57. 

Staley, J. T., Palmer, F. Adams, J. B. (1982). Microcolonial fungi common inhabitants on desert rocks. Science, 215, 1093-5. 

Subaerial rock communities metabolize under conditions of limited water availability and high solar and cosmic irradiation levels and can be found even on desert rocks and at high altitudes. In these places, they have found an ideal environment that allows for a stressful but less competitive existence. In more favourable conditions, these communities are quickly succeeded by more developed but less stress-tolerant symbiotic lichen or... 

Hungate, B., Danin, A., Pellerin, N.B., Stemmier, J., Kjellander, P., Adams, J.B. Staley, J.T. (1987) Characterization of manganese-oxidizing (Mnll —> MnlV) bacteria from Negev Desert rock varnish implications in desert varnish formation. Canadian Journal of Microbiology 33, 939-943. 

The upper temperature limit for the growth of phototrophic eukaryotes is 55-60°C. Certain cyanobacteria are thermophiles, with temperature maxima as high as 75°C. As a result, they constitute the dominant or almost the exclusive photosynthetic population of hot springs. Thermotolerance seems to be the major factor which makes cyanobacteria the most important agents of photosynthesis in deserts. They develop as a subsurface layer in desert rocks, in microfissures where water is trapped by condensation at night. 

Banerjee, M., Whitton, B.A. and Wynn-Williams, D.D. (2000a) Surface phosphomonoesterase activity of a natural immobilized system Chroococcidiopsis in an Antarctic desert rock. Journal of Applied Phycology 1 2, 549-552... 

Friedman I, Rafter A, Smith GI (1995) A thermeil, isotopic, and chemical study of Lake Vanda and Don Juan Pond, Antarctica. In Elliot DH, Blaisdell GL (eds) Contributions to Antarctic Research IV. Antarctic Research Series, vol. 67—. American Geophysical Union, Washington, DC, pp 177-194 Friedmemn El (1977) Microorganisms in Antarctic desert rocks from dry vrilleys and Dufek Massif. Antarctic J US 12(4) 26-29... 

Fig. 13.4 Time series of measured ambient temperatures (darker line) and modelled module temperature (crystalline Silicon) for an arid location in the USA (desert rock)...

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