ABSTRACT
Soil organic matter is a complex and varied mixture of organic substances (i.e. partially recomposed and partially synthesized) which is derived from living entity (plants and animals). In most cultivated soils, the percentage of SOM is small, but their effects on soil function are profound because, it exerts a dominant influence on many physical, chemical and biological properties of soils, especially in the surface soils. The remains of plants, animals and microorganisms are continuously broken down in the soil, and new substances are synthesized by other organisms. When any organic residues/organic materials are added in the soil, they are subjected to microbial decomposition. The time required to complete decomposition process may range from days to years, depending mainly on two broad factors: environmental conditions and quality of added organic materials in the soils. Addition of organic matter improves the most of physical, chemical and biological property of soils which results in improves the soil health and crop productivity.
