Soil in an important natural resource. Soil is the thin layer of loose mixture of small rock particles and rotting organic matter that covers much of the world’s land surface and all life depends on it directly or indirectly. Soil forms slowly and destroy easily an hence must be conserved. It is composed of varying proportions of silica, clay, chalk and humus. Soil Profile: i) Topsoil ii) subsoil

Soil formation differs according to the effect of various environmental factors which include parent material, climatic conditions, living things such as plants and animals and the surface relief and drainage. Process of soil formation is called pedogenesis ( process of wear and tear). Humus adds to the fertility of soil.