What Is Weathering

Weathering is a breaking down of big rocks into small rocks by the action of natural forces such as water,glaciers,wind and roots of plants etc.

Why are earthworms called farmers friend?

Earthworms are called farmers friend because they improve the texture of soil.By burrowing into the soil they make it loose thus allowing air to enter into it and water to drain from it.They also form channels in the soil for roots to spread through.

What does soil consist of?
Soil is mainly made up of two main components.

Tiny bits of mineral particles which come from large rocks.These minerals include salts of iron,calcium,potassium,magnesium and phosperous.Many of these minerals are needed by the plants for the growth.

The other component is humus which is dark brown in colour and consists of decaying remains of plants and animals.

Describe the types of soil

Top soil - Humus and the smallest particles of rock form the upper layers of soil called top soil or A horizon.The presence of humus gives it a dark color.It is the layer containing the most nutrients for plants.The roots of most plants are confined  to this layer.Humas makes this layer porous and fertile.

Subsoil- This is the layer below the top soil.Subsoil  does not have much humus and is light in color than topsoil.It is made  up mostly of rock bits and some nutrients such as soluble and iron oxides.Rainwater collects this layer.

Parent Rock- Below the subsoil is the parent rock or the C horizon which consists of small pieces of rocks with cracks and cravices.The particles of rocks found  in soil come from weathered rock in the c-horizon.Below this is solid rock called the bedrock.It is non-porous.Rainwater gathers over it to form the water table.