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Luvisols
Definition
The dominant characteristic of Luvisols is the textural
differentiation in the profile showing a surface horizon
depleted in clay and accumulation of clay in a subsurface
argic horizon. Luvisols are classified as Alfisols in USDA Soil
Taxonomy. These soils have a cation exchange capacity equal
-1
to or greater than 24 cmol kg within 100 cm from the soil
c
surface.
Distribution
Luvisols cover 4,062 million rais worldwide with
major distribution in western Europe, the Mediterranean region,
North America and Southern Australia. In subtropical regions,
they occur mainly in young land areas.
In Thailand, these soils cover countrywide about 25.5
million rais, mostly distributing in the north region, followed
by the central, east, northeast, and west regions, respectively.
Formation
One of the main characteristics of Luvisols is that
they have argic horizons, with clay accumulation along with
the soil depth. Clay migration occurs by the detachment of
soil particles, leading to clay transport from the surface to
accumulate down cracks and pores in the subsoils.
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