Soil layers known as horizons "طبقات التربة المعروفة آفاق"

Horizon = each layer of soil
Soil profile = the cross-section of soil as a whole
Topsoil = inorganic and organic material most nutritive for plants
Leaching = dissolved particles move down through horizons
Litter = surface deposits of leaves, branches, mosses, animal waste

O Horizon – peat deposits
A Horizon – topsoil
B Horizon  = subsoil, hardpan
C Horizon = broken parent material
R Horizon = unaltered parent material
W Horizon = distinct layer of water in some soils
Permafrost = some arctic soils contain a perennially frozen layer