Classifications: International WRB and U.S. Soil Taxonomy - Major Soil Groups of the World - page 124

Table 4.6 The Reference Soil Groups of the WRB.

Rs Group Simplied Definition Rs Group Simplified Definition

Ferralsols B with 1/1 type clay Plinthosols Layers indurated by iron

minerals and gibbsite

Acrisols Argic B with 1/1 clay Durisols With accumulation

minerals; low base of silica

saturation (USA: Ultisols

to some extent)

Alisols Argic B with 2/1 clay Lixisols Argic B with 1/1 clay

minerals and exchangeable minerals, high base

Al (degraded Nitosols) saturation (USA: Alfisols

to some extent)

Nitisols Red soils, clayey, rich Vertisols Dark, with swelling clays,

in iron and 2/1 or shrinkage cracks,

1/1 clay minerals slickensides

Cambisols Brown soils with poor Andosols Young soils in volcanic

horizon differentiation deposits

Luvisols Progressive appearance Phaeozems Leached soils (Phaeozems)

of soils with increasingly in the north; lime or gypsum

Albeluvisols contrasted horizons with Chernozems accumulations in the south

regard to colour and clay (Kastanozem), often rich

Planosols content Kastanozems in organic matter

(Chernozems)