Paragraph on “Soil an Invaluable Resource” complete paragraph for Class 9, Class 10, Class 11 and Class 12
Soil an Invaluable Resource
One of the Earth’s most valuable basic resource is the soil. It is formed of several layers, ‘Humus’ made of decaying leaves etc 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 erode away the top layers of barren land thus making the soil infertile. Fertility of such soils is increased by adding natural or artificial fertilisers and through crop rotation.