Question

What is meant by soil profile? Explain.

Answer 1

Hint: The earth contains many different layers. Of these layers, the earth’s crust is the layer that is present on the surface of the planet. The topmost layer of the crust is made up of soil that is composed of a variety of different layers.

Complete answer:
The soil profile is a vertical section of this soil that shows all of the different layers that are present in the soil. All of these layers are divided into several different parts:
1)Organic Layer (O): This is the first layer of the soil that, as the name suggests, is made up of organic material. This layer comprises materials such as fallen leaves, decomposing animal carcasses, and other organic matter that is left on top of the soil.
2)Topsoil (A): The next layer has partly decomposed organic matter that is being broken down into its base components. This material is known as humus and it consists of minerals and organic materials like nitrogen that help to fertilize plants.
3) Subsoil (B): This layer has all of the broken down matter that has seeped down from the above layers. It is much harder and more compact than the other layers above it. It has less soluble minerals like iron, aluminium and usually constitutes some amount of clay.
4) Parent material (C): The parent material or the substratum is a deposition of the majority of the insoluble inorganic materials. This layer is generally highly compacted and consists of broken-up bedrock.
5) Bedrock (R): The bedrock is the bottom most layer of the soil. It is extremely hard and contains broken down rocks.

Note:
The soil profile is a depiction of how an undisturbed layer of soil looks. These layers are formed over many different years. The planets generally grow on the upper layers of this soil profile, namely in the topsoil and organic layers.