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The origin of podzols and distribution of elements induced by podzolization.
Pánik, Róbert ; Mihaljevič, Martin (advisor) ; Borůvka, Luboš (referee)
Part I. The purpose of this work is to review publications and present a novel approach to the interpretation of available data in attempt to explain process of podzolization. First, we consider all major inputs that affect podzol formation from global to microscopic scale - climate, parent material, vegetation, mycorrhizal fungi, and fire regime in the podzol areas. Important role of fire-produced charcoal in the podzolization process due to its specific properties is also considered. Subsequently, physico-chemical transitions upon the downward progression of podzolization front (i.e., C to Bs, Bs to Bhs, and Bhs to E) are treated, in conjunction with the characterization of secondary phases that precipitate in the Bs horizon, as well as the demonstration of the major role of organic matter in the formation of podzols. Organic carriers exuded by plants and fungi are shown both to decrease mobility of certain elements (e. g., Ca, Al) by the formation of secondary solid phases, and also to increase mobility of otherwise unavailable elements (e.g., Fe) by their chelating abilities. Special emphasis is given to siderophores, group of organic substances that show high and specific affinity for Fe3+ chelation over a wide range of pH. Finally, spatial and temporal trends of podzolization and podzol...
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