Introduction

One of the important natural resource is soil. Soil supports the growth and developments of plants by several ways like holding the roots firmly, supplying water, minerals, and nutrients. Apart from plants growth it is also usefully and home for many organisms. Soil is one of the most essential thing require for agriculture. Agriculture provides food, clothing and shelter for all. Soil is thus an inseparable part of our life. The earthy fragrance of soil after the first rain is always refreshing.Soil science has two main branches of study: Edaphology and Pedology (from Greek: pedon, "soil"; and logos, "study"). Pedology is focused on the formation, morphology, and classification of soils in their natural environment. whereas Edaphology is concerned with the influence of soils on organisms.

The upper layer of earth is known as soil. And it is the most important natural resource essential for survival and development.

Important facts on soil

• Land covers 20% of the earth’s surface.
• Top most layer of earth’s crust is called Top soil. It is a mixture of mineral (soil) particles and humus.
• Soil particles are formed from rocks and the chemical composition of soil particles depends on the rock from which it is formed.
• Top soil is important for biological activity as it holds roots of all plants and contains different types of animals and micro-organisms.
• Loss of top soil is called soil erosion and it occurs due to natural and man - made causes.
• Floods and winds are the natural causes for soil erosion. Deforestation, overgrazing and improper tilling are man - made causes for soil erosion.
• Soil erosion is prevented by proper land management, preventing overgrazing, deforestation and Jhoom type farming and by restoring of forest and grass cover.
• Soil is another natural resource, which is rather most precious of all resources, as it is essential for our survival as well as all other life forms.

It provides

• food and fodder
• clothing
• provides anchorage to the plants
• water and minerals to the plants, and water for various human needs, irrigation and industry
• Home to a number of soil organisms.

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