In this world all living organisms require a constant supply of nutrients for growth. The
death and decomposition of plants and animals, with release of nutrients constitutes an essential link in the maintenance of nutrient cycles. When an organism dies, an initial
period of rapid leaching takes place and populations of macromolecules. The dead organism is disintegrated beyond recognition. Enzymic action breaks down the disintegrating parts of the litter. Animals invade and either eat the rapidly recolonized by micro- organisms, and the litter biomass decreases. It becomes simpler in structure and chemical composition.