Soil of India; Classification

Soil of India.

Meaning of Soil

Soil is the upper layer of earth's surface consisting of mixture of air, water, minerals particles and some organic materials etc which provides support to growth of plants by serving as a reservoir of water and essential nutrients.

The composition and properties of soil is varies that depends upon location, geographical factors, climate conditions etc. Following are the main components of soil.

1)Soil contains 45% of minerals particles such as sand, silt, clay etc sand is largest and clay is smallest particles of soil.

2)Soil have 25% of water content which which is essential for growth of plants.

3)Soil allows the moment of air in plants which is crucial for oxygen supply to plant roots.

4) Remaining 5% includes organic materials comprised of decaying plants and animals such as leaves roots and microorganisms etc.

Soil profile

Soil profile is vertical selection of soil that shows various layers or horizon of soil from surface to bedrock. Each layer of soil have distinct characteristics and properties. Some common soil horizons are O A E B C and R horizons.

1)O Horizon

O horizon is top most layer of earth consisting of decaying plants and animals such as dried leaves, microorganisms, grass, dead leaves, small rocks and twigs etc.

2)A Horizon (Topsoil)

This is the human layer on the soil which consists of organic materials, minerals and nutrients. A horizon is most fertile layer which is essential for growth of plants.

3)E Horizon(Eluviation horizon)

E horizon is related with leaching or removal of minerals and nutrients from A and O horizons, in this horizon the materials like clay, iron, aluminium are leached from soil.

4)B Horizon

B horizon it is known as subsoil, is a layer found beneath the A horizon(Topsoil) and above C horizon. This layer is more harder and compact than A horizon and it has less humus, minerals and organic matters.

5)C horizon

C horizon of soil found above the bedrocks which  also known as saprolite consisting of partially weathered rocks or unconsolidated materials.

6)R horizon

The R horizon of soil, often referred to as the bedrock or unweathered parent material, is the layer located below the C horizon. It consists of solid rock or unaltered geological material that has not been significantly weathered or broken down by soil-forming processes.

Classification of Soil in India

In India soil can be classified based on  different geographical factors, textures, Composition etc. Some of important types of soil found in India are follows.

1) Alluvial soil

Alluvial soil is most fertile type of soil found in northern plains and river valleys of India. It is formed by deposition of clay and silt carried by rivers. Humus, lime and organic matters are present in this soil. This is best for cultivation of wheat, rice, sugarcane, oilseeds etc. The alluvial soil in Indo-Gangetic plain is deposited by ganga, Brahmaputra, Narmada Tapi plains.

2) Black soil

Black soil is also known as Regur soil, which is found in Deccan plateau of India. It has high water retention capacity characterized by its deep black or dark colour. Black soil is best for cotton cultivation. It is founded in states of Maharashtra, Gujarat, Madhya pradesh and some parts of southern India.

3)Red soil

Red soil is also known as Latosols is another important type of soil seen mainly in low rainfall areas. It is characterized by reddish to brown colour from presence of iron oxide. Red soil are poor in nutrients and organic matters compared to other soil groups. It is founded in southern India in the states like Tamilnadu, Andra Pradesh, Karnataka etc. It is suitable for cultivation of wheat, cotton, oilseeds, potato etc.

4) Laterite Soil

The term Laterite is derived from Latin word Later which means Brick. This type of soil is founded in tropical and subtropical regions with high rainfall and high temperature. Laterite Soil is rich in iron content makes soil red to brown even yellow in colour. This is founded in western and coastal areas of western ghats, some parts of Goa, Kerala and Konkan regions.

5) Desert soil

As the name suggests it is found in desert or arid regions with extremely low rainfall and high temperature. It has high salt content with low nitrogen. Desert soil is less fertile for agriculture due to lack of moisture and humus.

6)Mountain Soil

This is a high altitude soil found in hilly and mountainous areas, it is less fertile due to erosion.

7)Forest Soil

Found in the Himalayan region, it is rich in organic matter.