Types of Soil

The top most layer of the soil which contains humus and living organisms is called the topsoil. The amount of humus and the depth of the soil determine the type of plant that can be grown in the top soil.

Types of soil: On the basis of particle size, soils are classified as sand, silt and clay. Sand contains particles of largest size, clay the smallest and silts the intermediate ones.

Sand, being very porous, allows air and water to pass through it. So, it is not suitable for growing plants. This type of soil is called sandy soil.

Clay forms a sticky paste with water. It does not allow air to reach the roots of plants. So, it too is not suitable for the growth of plants.This type of soil is callled as clayey soil.

Loam is a mixture of sand, silt and clay. It is just the right kind of soil for growing plants. Such soils are known as Loamy soil.

Other type of soil have much smaller particles to sandy soil and is made up of rock and other mineral particles, which are smaller than sand and and larger than clay. It is the smooth and fine quality of the soil that holds water better than sand. This type of soil is called as silt soil.

Based on the proportion of sand, silt, clay, and humus present, soil can be sandy, clayey.

SandySoil	Clayey Soil	Loamy soil
More than two third of sandy soil is sand and about one third is clay.	More than two - third of clayey soil is clay.	Loamy soil has sand and silt in equal amounts, about two fifth each. One fifth of loamy soil is clay.
It is made up of large particles with large air spaces.	It is made up of fine particles with small air spaces.	It has high humus content.
Its porosity prevents retention of water. So it dries up early.	It retains moisture and becomes very sticky when wet.	It is porous and also holds moisture.
It is well suited for fruit and vegetable cultivation.	It is good for making pots.	It is god for cultivation of crops and gardening.

Geographically, Indian soil can be classified into following types:

1. Red soil : This soil is red in colour due to the presence of large amounts of iron oxide.

2. Black soil : It is rich in the minerals, iron and magnesium. This soil is suitable for the growth of sugarcane and cotton.

3. Alluvial soil : This sandy, formed by the weathering of rocks is brought down by flowiing rivers fro the mountains. It is vary fertile and rich in humus. It is suitable for the cultivation of wheat, rice and sugarcane.

4. Desert soil : This sandy soil does not hold much water. Cacti, Date palm, Coconut palm, etc. which do not need much water grow in this type of soil.

5. Mountain soil : This is highly fertile soil contains the highest humus content.

6. Laterite soil : This soil is found in regions of heavy rainfall. It is good for the growth of plantation crops like coffee, tea, coconut anf banana.