What do the numbers (1,2,3, and 4) indicate in the below given picture? Describe each layer in detail. Soi Profile 2 Δ
Answers
Explanation:
Different Types of Soil
These lead us to the various kinds of soil. The soil is divided into the following:
Topsoil
Subsoil
Parent Rock
Layers of Soil
The soil scientists (also known as pedologists) have identified an exciting way to determine the soil profile model through the capital letters O, A, B, C, and E. All the above layers have unique and different characteristics from each other.
Sometimes it is noted that this layer gets eroded due to various factors present in the environment like excess rain or wind can erode the top layer removing all minerals from the soil.
The soil profile diagram shows the three major surfaces of the soil consisting of A, B, and C, which are the surface horizon, the subsoil, and the substratum. Again soil profile consists of an organic mineral coat at the surface (O). This surface provides the soil with all the natural minerals.
1. O-Horizon:
The O-Horizon soil has organic materials like dried leaves, small rocks, fallen trees, and other organic matter that can be decomposed. It has about 20 to 30 percent of organic matter in it. The colour of the soil is generally black brown and dark brown due to the existence of organic matter.
2. A-Horizon:
The A-Horizon Layer consists of organic material and is famously called a humus layer. It is the uppermost layer of the soil that consists of dark decomposed matter, known as humus. Humus provides nutrients to the soil, therefore, making the soil more fertile. It also maintains the soil’s life. Since it increases soil’s water holding capacity, this layer is soft and can retain more water than any other layer. Many living organisms are present in this layer, for example, beetles, worms etc.
3. E-Horizon:
The letter E denotes the master horizon, which is subsurface to all the layers of soil. It is present only in the forested regions. The colour of the soil is light. The letter E means eluviated horizon. The movement of the dissolved particles from the A- Horizon takes place here.
4. B-Horizon:
B-Horizon is also known as subsoil because of its presence below the topsoil. It is the layer of soil that absorbs all the rainwater that flows through the topsoil. It accumulates the rain for further usage. It has humus but in lesser quantity than the A- horizon, organic matter, and soluble minerals. Since this layer contains large amounts of minerals, this layer is generally hard and compact.
5. C-Horizon:
Another layer of soil that presents below the B-Horizon; this layer consists of less weathered rocks or parent rocks. It doesn’t contain any organic substance in it. It is also known as saprolite.
6. R-Horizon:
R-Horizon is the layer that has partially weathered rocks or unweathered rocks. It is also known to be the foundation or the base layer of the soil. You can find manganese, granite, limestone, and basalt in this layer.