Table of Contents
Decomposition
- Decomposition of biomass and organic matter is also an important process in an ecosystem.
- While productivity involves synthesis and building processes, the decomposition involves the breakdown of complex organic matter into inorganic raw materals like carbon dioxide, water and various nutrients.
- The upper layer of Soil is the main site for decomposition processes in the ecosystem.
- Dead plant parts and animal remains (undecomposed or partially decomposed) are called detritus.
- Dried plant parts, like leaves, bark, flowers, etc., and dead remains of animals, including faecal matter, drop over the soil and constitute the above-ground detritus (also known as ltter fall).
- The below-ground detritus is primarily composed of dead roots (also called root detritus).
- In the course of time, as a result of decomposition, the detritus becomes Completely disappeared. (this decomposition is also called biodegradation).
Mechanism of Decomposition
The mechanism of decomposition involves various processes like, fragmentation of detritus, leaching and catabolism.
(i) Fragmentation of detritus
The fragmentation of detritus occurs mainly due to the action of detritus feeding invertebrates (detritivores).
The detrivores (like earthworm) feed on detritus and break it into smaller particles. The detritus gets pulverized when passing through the digestive atracts of animals.
Due to fragmentation, the surface area of detritus particles is greatly increased.
(i) Leaching
Water percolating through soil removes soluble substances (e.g., sugars, several nutrients) from the fragmented detritus due to leaching action.
(ii) Catabolism
- The extracellular enzymes released by bacteria and fungi (decomposers) carry out catabolism of the decomposing detritus.
- The enzymes convert the decomposing detritus to simpler compounds and inorganic substances.
- It is important to know that all the three decomposition processes operate simultaneously on the detritus.
- The catabolism helps in the humification and mineralisation of the soil.
- Humification leads to accumulation of a dark- coloured amorphous substance,
Factors Affecting Decomposition
- The rate of decomposition is mainly affected by climatic tactors and chemical nature of the detritus.
- Temperature and the soil moisture are two very important climatic factors which directly influence the rate of decomposition.
- High temperature and high soil moisture accelerate the rate of decomposition.
- The chemical quality of the detritus is determined by the relative amount of water-soluble substances (like sugars), polyphenols, lignin and chitin etc.
- The rate of decomposition is higher if water soluble substances like sugars are higher in detritus.
CONCLUSION:-
decomposition involves the breakdown of complex organic matter into inorganic raw materials like carbon dioxide, water and various nutrients. Decomposition helps in the recycling of minerals. The mechanism of decomposition involves various processes like, fragmentation of detritus, leaching and catabolism. The detrivores (like earthworm) feed on detritus and break it into smaller particles. Water percolating through soil removes soluble substances (e.g., sugars, several nutrients) from the fragmented detritus due to leaching action. The extracellular enzymes released by bacteria and fungi (decomposers) carry out catabolism of the decomposing detritus and convert the decomposing detritus to simpler compounds and inorganic substances