Calcic Vertisol TZ
A representative soil profile of a Vertisol from Tanzania. (Photos courtesy of Stefaan Dondeyne, revised.)
Vertisols are heavy clay soils with a high proportion of swelling clays. These soils form deep wide cracks from the surface downward when they dry out, which happens in most years. The name Vertisols (from Latin vertere, to turn) refers to the constant internal turnover (churning) of soil material. Common local names for Vertisols are Black cotton soils and Regur (India), Black turf soils (South Africa) or Margalites (Indonesia). In national soil classification systems they are called Slitozems or Dark vertic soils (Russia), Vertosols (Australia), Vertissolos (Brazil) and Vertisols (United States of America).
Calcic (from Latin calx, lime): having a calcic horizon starting ≤ 100 cm from the soil surface. A calcic horizon is a horizon in which secondary calcium carbonate (CaCO3) has accumulated in a diffuse form (calcium carbonate occurs as impregnation of the matrix or in the form of fine calcite particles of < 1 mm, dispersed in the matrix) or as discontinuous concentrations (veins, pseudomycelia, coatings, soft and/or hard nodules).
For more information about soil classification using the WRB system, visit:
Calcic Vertisol TZ
A representative soil profile of a Vertisol from Tanzania. (Photos courtesy of Stefaan Dondeyne, revised.)
Vertisols are heavy clay soils with a high proportion of swelling clays. These soils form deep wide cracks from the surface downward when they dry out, which happens in most years. The name Vertisols (from Latin vertere, to turn) refers to the constant internal turnover (churning) of soil material. Common local names for Vertisols are Black cotton soils and Regur (India), Black turf soils (South Africa) or Margalites (Indonesia). In national soil classification systems they are called Slitozems or Dark vertic soils (Russia), Vertosols (Australia), Vertissolos (Brazil) and Vertisols (United States of America).
Calcic (from Latin calx, lime): having a calcic horizon starting ≤ 100 cm from the soil surface. A calcic horizon is a horizon in which secondary calcium carbonate (CaCO3) has accumulated in a diffuse form (calcium carbonate occurs as impregnation of the matrix or in the form of fine calcite particles of < 1 mm, dispersed in the matrix) or as discontinuous concentrations (veins, pseudomycelia, coatings, soft and/or hard nodules).
For more information about soil classification using the WRB system, visit: