Decomposers - Biotic Components

Also known as saprotrophs. Mostly, these are microscopic and are heterotrophic in nature. Decomposer organisms obtain their energy and nutrients by degrading dead organic matter. When plants and animals die, their bodies are still a source of energy and nutrients, as are their waste products such as urine and faces which they discard throughout their life times. These organic remains are decomposed by micro-organisms, namely fungi and bacteria which grow saprophytically on these remains. They secrete digestive enzymes from their bodies on the dead and wasted materials.

sub sequently absorbing the products of digestion. The rate of digestion is variable. The organic matter of animal wastes such as urine, faeces and corpses is consumed within a matter of weeks whereas fallen leaves and branches may take years to decomposes. During the decomposition of wood fungi act and produce an enzyme cellulase, that softens the wood. This enables the small animals to penetrate and ingest the material. Fragments of decomposing material are called detritus, and many small animals Iced on these, contributing to the process of breakdown. They are called detritivores. Because of the combined activities of the true decomposers (fungi .and bacteria) and detritivores (animals), in the breakdown (decomposition) of materials, they are sometimes collectively referred to as decomposers. Although, strictly the term decomposer relates to saprophytic organisms, Some typical terrestrial detritivores are: earthworm, woodlice, millipedes and other smaller (< 0.5 mm) animals such as mites, springtail and nematodes.