Question

Which of the following show the correct arrangement of different layers of the soil?
A.) Topsoil, Subsoil, Bedrock
B.) Subsoil, Bedrock, Topsoil
C.) Bedrock, Topsoil, Subsoil
D.) Subsoil, Topsoil, Bedrock

Answer 1

Hint: Soil has different types of layers. These layers collectively form different horizons of the soil. The first layer or top most layer of the soil is rich in humus and the next layer is made up of rocks.

Complete step by step answer:
As we know that Soil is a natural resource which supports the growth of the plants and it is generally holding the roots firmly and supplying water and nutrients . The soil is composed of different layers. These layers are: Topsoil, Subsoil and Bedrock.
The top soil is the uppermost layer of the soil. This layer is rich in humus and minerals which makes the soil fertile and provides nutrients to the plants. Here, humus means a dark and organic material that is formed in the soil when plant and animals matter decays. In this layer, the seeds germinate and roots of the plants also grow in this layer or in this region.
The subsoil is another layer of the soil which lies just below the topsoil. This layer contains more humus and less organic matter. This layer of soil has a lesser amount of humus than that of top soil. Due to less amount of humus it is lighter in color. But this layer is rich in minerals.
 The Bedrock is the layer which lies just below that subsoil. It is also known as parent rock. This layer is very hard because it is made up of stones and rocks. This layer does not contain any organic matter. This layer is hard and difficult to dig with a spade.
As we know that the first layer of soil is topsoil , the middle layer of soil is subsoil and after the sub soil there is bedrock. Therefore, the correct arrangement of layers is top soil, subsoil, bedrock.

Hence, A.) is the correct answer.

Note: Soil is partly made up of dead and decaying plants and animals remaining and it is also formed when rock is broken into small pieces. It takes thousands of years to create an inch of topsoil.