Types Of Soil – Definition, Properties & Importance

By /

In this hall, we are going to be looking at the following headings: Soil Definition, types of soil, Soil Properties and importance of oil.

Table Of Contents

At the end of this article, student should be able to:

  1. Know the definition of soil
  2. List the types of soil
  3. Outline the importance of soil
  4. Describe the properties of soil

Definition: Soil is defined as the uppermost layer of the earth crust which provides support and nutrients for plant growth. There are three main types of soil: these are: sandy soil, clay Soil and loamy soil.

Read Also Components of Soil and importance

TYPES OF SOIL

Below are the various types of soil:

  1. Sandy soil
  2. Clay soil
  3. Loamy soil

SANDY SOIL: Sandy soil is said to be Sandy if the proportion of sand particles in a sample of the soil is very high. The particles are mainly quartz (siO2) and having a size of 0.02mm to 2.0mm in diameter.

PROPERTIES OF SANDY SOIL

  • Sandy soil is a coarse, grained and gritty.
  • It is loose with large pore spaces.
  • It absorbs and loses water easily.
  • It is not sticky, when wet, hence, it cannot form a cast or ribbon.
  • It is well aerated with low water holding capacity.
  • Percolation in sandy soil is high but capillarity is low.
  • Sandy soil heat up easily during the day and cools down quickly during the night.
  • It support leaching, hence it is low in plant nutrients.
  • it does not support water logging and erosion.
  • Sandy soil is low in plant nutrients, hence it does not support crop cultivation.
  • Sandy soil has grey or brownish colour.

METHODS OF IMPROVING SANDY-SOIL

Sandy soil can be improved through the following agricultural practices:

  1. Planting cover crops: Cover crops helps to provide shades, prevent erosion and add more nutrient to the Soil.
  2. Application of compost manure: Compost manual helps to bind the sand particles together and also add (humus) nutrient to the Soil.
  3. Application of farmyard manure: This will also improve the structure of the soil as well as add nutrients to the soil.
  4. Mulching the Soil: Mulching sandy soil prevent water loss through evaporation and nutrient loss by water erosion.
  5. Avoidance of bush burning: Bush burning promote soil erosion, kills soils organisms and removes organic matter which can contribute to the fertility of the soil.

ECONOMIC IMPORTANCE OF SANDY-SOIL

  • It is good for the Cultivation of few crops such as cotton, groundnut, cassava, etc.
  • It is also used for in building construction, especially in combination with cement and water in block moulding.

CLAY SOIL

Definition of Clay Soil: Clay Soil is said to be clayey if the proportion of clay in a sample of the soil is very high. The relative size of a clay particles is less than 0.002mm in diameter. It is a heavy type of soil because it is difficult to walk on or cultivate.

PROPERTIES OF CLAY SOIL

  • Clay particles are fine, powdery and smooth when dry.
  • The particles are sticky and mouldy when wet.
  • The particles are tightly bound together with little pore (air) spaces.
  • It is poorly aerated with high water holding capacity.
  • The structure is granular and does not lose water easily.
  • It does not support leaching, hence it contains plant nutrients.
  • Percolation in clay soil is low but capillarity is high.
  • It can easily form a ribbon or cast when moulded.
  • It is hard when dry and sticky when wet.
  • It support waterlogging and erosion.
  • It has a grey or brownish colour.

Note: Clay soil can be improved through liming and addition of organic manure.

LOAMY SOIL

Definition of Loamy Soil: Loamy soil is a mixture of sand and clay particles with high proportion of organic matter. Loamy soil is more effective than other clay or sandy soil. If a type of soil is described as Sandy loam, it means that the proportion of soil is high and if it is a clay loamy, it shows that the proportion of clay is high while that of Sandy is low.

PROPERTIES OF LOAMY SOIL

  • Loamy soil is moist, loose with moderate sized pore spaces.
  • The structure breaks easily when wet and friable when dry.
  • It has non powdery and non sticky texture.
  • It can easily be worked on or cultivated.
  • It does not support erosion and water login.
  • it contains lots of organic matter (humus).
  • It is well aerated and it can hold water.
  • It contains plant nutrients, hence it is the best soil for the cultivation of crops e.g maize, Rice, cowpea, cassava, yam, tomatoes, okra, millet, pepper.
  • It is dark brown or black in colour.

General Importance of Soil

Soil is crucial for various reasons, including supporting plant growth, providing habitats for organisms, regulating water flow, storing carbon, and contributing to nutrient cycling. It plays a fundamental role in sustaining ecosystems and supporting agriculture, making it essential for human survival and the health of the planet.

Here are the Importance of Soil

  1. Plant Growth
  2. Biodiversity
  3. Water Regulation
  4. Nutrient Cycling
  5. Carbon Storage
  6. Support for Structures
  7. Waste Decomposition
  8. Agricultural Productivity
  9. Habitat for Microorganisms
  10. Cultural and Recreational Value
  11. Erosion prevention.

Plant Growth: Soil provides a medium for plants to anchor their roots and access essential nutrients and water.

Biodiversity: Soil supports a diverse range of organisms, contributing to ecosystem health and balance.

Water Regulation: Soil acts as a natural filter, regulating water flow, preventing erosion, and influencing groundwater recharge.

Nutrient Cycling: Soil is a vital component in the cycling of nutrients, essential for plant and microbial life.

Carbon Storage: Soil stores a significant amount of carbon, playing a role in climate regulation and mitigating the impacts of climate change.

Support for Structures: It provides a foundation for buildings and infrastructure, contributing to the stability of structures.

Waste Decomposition: It is involved in the decomposition of organic matter, recycling nutrients and breaking down pollutants.

Agricultural Productivity: The majority of our food comes from the soil, making it crucial for global food security.

Habitat for Microorganisms: It is a home to a vast array of microorganisms that contribute to nutrient cycling and soil fertility.

Cultural and Recreational Value: It is often tied to cultural practices and provides spaces for recreational activities, emphasizing it’s social importance.

Revision Questions

  1. What is Soil?
  2. Mention 3 types of soil
  3. State five properties of Sandy soil
  4. List five importance of soil in agriculture
Scroll to Top