Weathering

Have we ever imagined how this soil was formed?

To discuss about it, let us first see this picture.

What are we seeing in this picture?

All that we can see is

At first bedrock becomes disintegrated by the force of physical and chemical weathering.

Then this disintegrated parts becomes an ideal surface for mosses to grow up.

These mosses provide organic matter and nutrients to some organisms.

These organisms, organic matter and mosses create further a condition that is good for growing plants and thus plants grow.

And after thousands of year, the dead part of those plants become organic matter and create soil horizons.

In this post we will learn only about the weathering and it's agents.

Weathering

Weathering is a biochemical process that involves both destruction and synthesis.

Weathering can be of three types:

Physical Weathering: This involves the disintegration of rocks into smaller fragments by physical weathering agents.

[ To Know about Rocks and Minerals, Click Here ]

Physical weathering agents are:


     1. Wind: The force of wind carries along small pieces of soil which hit against the surface of parent rock causing it to disintegrate into smaller soil particles.
     2. Water: Moving water or rain has a grinding effect against the surface of the parent rock. This causes the rock to disintegrate into smaller soil particles.
     3. Freezing and thawing: Soils at cold regions get freeze and thaw. This 2 action can be an agent of weathering.
     4. Temperature: Temperature is another major agent of physical weathering. At high temperature during day, the rocks expand and at night when temperature is low, the rocks contract. This expansion and contraction can breakdown the rocks.

Chemical Weathering: Chemical weathering involves the breakdown of rocks by chemical action. This action can be occurred by formation of acids, hydrolysis action etc.


Agents of chemical weathering are:



     1.Hydrolysis: Water reacting with soluble minerals in the rocks loosening and breaking them into smaller particles.
     2.Oxidation: Reaction of rock minerals with oxygen to form oxide compounds which easily break up.
     3.Carbonation: Carbon dioxide dissolves in water forming weak carbonic acid which reacts with rocks.

Biological Weathering: This involves the action of living organisms, such as animals and plant materials.


Agents of biological weathering are: 

Termites, Earthworms, Moles, Millipedes etc.

Let's see some more pictures.