Publication date: November 2013
Source:Geoderma, Volumes 209–210
Author(s): J.G. Bockheim , A.E. Hartemink
In Soil Taxonomy three diagnostic subsurface horizons reflect clay enrichment: the argillic, kandic, and natric horizons. Clay illuviation is recognized in Soil Taxonomy at some level in 10 of the 12 orders, including the order (Alfisols, Ultisols), suborder (Aridisols), great group (Aridisols, Gelisols, Mollisols, Oxisols, Vertisols), and subgroup (Andisols, Aridisols, Inceptisols, Mollisols, Oxisols, Spodosols). Forty-four percent of the soil series in the USA contain taxonomically defined clay-enriched horizons. However, many other soils contain Bt horizons that do not qualify as an argillic or related horizons. Several soil-forming factors are important in their development, including udic and ustic soil climates, lithological discontinuities, parent materials enriched in carbonate-free clays and coarse fragments, well-drained conditions, backslopes rather than eroding shoulders, and a time interval of >
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Source:Geoderma, Volumes 209–210
Author(s): J.G. Bockheim , A.E. Hartemink
Graphical abstract
