The development of a soil from inorganic and organic material is a complex process. Weathering easy the physical and the chemical break down of rocks and the first step in soil development.weatherd
Soil profile
Vertical and horizontal movements of the materials in a soil system create a distinct layering, parallel to the surface, collectively called a soil profile. The layers are called zones or soil horizons.
The Horizon
O horizon
The O horizon consists entirely of plant litter and other organic material.The O horizon, when it is present, is the uppermost horizon. The O stands for 'organ.' You can think of dead plants and animal parts falling on the surface of the soil. Sometimes it's very recognizable and sometimes.
A Horizon
Topsoil is called the A horizon, the topsoil is usually the darkest layer of the soil because it has the highest proportion of organic material. The topsoil is the region of most intense biological activity: insects, worms, and other animals burrow through it and plants stretch their roots down into it.
E Horizon
Some soils have an E horizon, or zone of leaching, a light-coloured layer that is leached of iron-bearing components. This horizon is light in colour because it contains less organic material than the O and A horizons and little inorganic colouring material such as iron oxides.
B Horizon
The B horizon, or zone of accumulation, underlies the O, A, or E horizon.It is the horizon, characterized by the accumulation of calcium carbonate.This layer is lighter brown and holds more water than the topsoil because of the presence of iron and clay minerals. There is less organic material.
C Horizon
The C horizon lies directly over the unaltered parent material and consists of parent material partially altered by weathering processes.The C horizon may be oxidized.
R Horizon
The R horizon, or unaltered parent material, is the consolidated bedrock that underlies the soil. An R layer is bedrock. When a soil has direct contact with bedrock, especially close to the soil surface, the bedrock becomes a variable when developing land use management plans and its presence is noted in the soil profile description.
