Question

Are soil horizons 'A' and 'B' the same?

Answer 1

The 'A' horizon is the surface mineral layer. That part of the 'A' horizon having the largest accumulation of organic matter is called the A1 horizon. The A2 horizon is the layer of maximum leaching, or eluviation of clay and iron.
The 'B' horizon lies underneath the 'A' horizon and is commonly called the subsoil. It is the horizon of maximum accumulation or illuviation of clay, iron, aluminum, or other compounds leached from the A horizon. In some soils the B horizon forms through alteration of material in place rather than by illuviation.
(Eluviation- It is the transportation of dissolved or suspended material within the soil by the movement of water, when rainfall exceeds evaporation.
Illuviation- Accumulation of dissolved or suspended soil materials in one area or layer, formed as a result of leaching (percolation) from another.)