Question

How is soil formed? What is the role of humans in fertility of soil?

Answer 1

Soil: It is the uppermost layer of the earth that is a mixture of inorganic minerals and organic matter.

The formation of soil occurs through two processes:

1. Weathering:

• The process of breaking down bigger rocks into smaller mineral particles is called weathering.
• It takes place in three types. The physical weathering is caused due to climatic factors such as wind, rain, ice, snow, temperature, glaciers, and running water, the Chemical weathering includes a variety of chemical processes such as hydration, hydrolysis, reduction, and oxidation. and Biological weathering the process of weathering takes place by living organisms such as lichens and bryophytes, it is known as biological weathering.

2. Paedogensis:

• The process of development or formation of soil from rocky crust earth to mineralized soil. This takes place in two stages Humification and Mineralization.
• This process breaks down the organic materials by decomposition of bacteria and fungi resulting in humification and mineralization that enriches the soil and enables the existence of life in it.

The role of humans infertility in the soil is as follows:

1. Agricultural practices:

• Human grows many crops in a year and when the crops die, it decomposes into soil that enriches it.
• Some practices like mixed cropping and nitrogen-rich legumes increase many minerals.

2. The biological waste:

• this includes domestic waste like fruits and vegetables, and the excretion of animals enriches the soil fertility also when an organism like a human dies, the body decomposes into soil increasing its organic matter.