Science Project on “Soil an Invaluable Resource”, Project Topic on Human Beings, Animals Plants for Class 8, 9, 10 and 12 Students.

Soil an Invaluable Resource

One of the Earth’s most valuable basic resource is the soil. It is formed of several layers of ‘Humus’, made of decaying leaves etc. It covers the first layer of soil called the ‘Topsoil’. In this layer decayed plant and animal material is broken down by bacteria, insects and earthworms thus making it fertile. Below this lies the ‘Subsoil’ containing lesser organic material and reachable only by the roots of bigger plants and trees. A partly eroded and weathered rocky layer of broken rocks lies below the subsoil. Soils can be ‘Peaty’, ‘Chalky’, ‘Sandy’ or ‘Clayey’ in nature. Peaty soil is best for plants. Fertile soils are rich in humus, bacteria and minerals. Wind and water often wash away the top layers of barren land thus making the soil infertile. Fertility of such soils is increased by adding natural or artificial fertilizers and through crop rotation.