Decomposition – CBSE Class 12

Decomposition can be defined as the process of breaking down complex organic substances into smaller simpler particles by various microorganisms which can be later used. The term decomposition means the breaking down of particles or ” break down”.

What is Decomposition?

Decomposition is considered one of the most important processes for the survival of human beings and the nutrients from dead organisms are reabsorbed in the ground by these plants and converted into fruits and vegetables which are again consumed by humans for nutrients. It is mostly associated with the breaking down of complex structured organic matter into simpler forms that can be reused. This can be considered a metabolic process in which complex organic structure is raw materials and simple inorganic structures are the output. 

The microorganisms which start the process of breaking down organic matter are known as decomposers. Some Decomposers are bacteria, fungi, etc. They are known to initiate the process of decomposition. They consume the dead matter as their food. The buried dead and decaying animals and plants are acted upon by these decomposers and are broken down into simple inorganic matter like carbon dioxide, water, and nutrients. 

Process of Decomposition 

Decomposition is one of the major life processes that take place. It is essential for the survival of humans and plants. This cycle continues endlessly ensuring the availability of nutrients for the nest plants and animals. The older plants and animals die and decompose and are converted into nutrients that are absorbed by the plants, this ensures the proper growth of the plants.

There are majorly 5 steps involved in decomposition namely Fragmentation, Leaching, Catabolism, Catabolism, and  Mineralization. In this process, the dead organic raw material is referred to as detritus. 

Fragmentation

This is the initial stage of the breakdown process. Microorganisms in this stage break down the debris into tiny fragments.

Leaching

The smaller detritus typically contains enormous amounts of water-soluble nutrients, some of which may even be inorganic. In order to ensure that the inorganic nutrients are assimilated by the earth, all of these nutrients are dissolved in water and permeate into the soil below.

Catabolism

The debris is broken down into smaller pieces by the processes of fragmentation and leaching, and the inorganic nutrients are also eliminated, leaving only the organic component. Bacteria and other decomposers convert this organic material into smaller inorganic molecules.  

Humification

The soil develops a covering dark color as a result of this process. This layer, which is also known as humus, is composed of amorphous materials. This layer can’t simply dissolve because it is particularly resistant to the actions of microbes. The humus layer is very beneficial, contains a lot of nutrients, and gives the soil fertility. 

Mineralization

This step marks the end of the process of decomposition. In this step, the humus is broken down into inorganic nutrients and hence the process of decomposition is complete. 

Factors Affecting Decomposition

The following are factors that affects the decomposition process those are:

Matter Quality

The most important factor affecting decomposition is the quality of matter to be decomposed. The rate of decomposition is affected by the type of substance the detritus is made up of.

Temperature

As we know the process of decomposition is carried out by microorganisms.  Bacteria are known to grow better in higher temperatures. The number of bacteria present multiplies for every 10-degree rise in temperature. So higher temperature ensures faster decomposition.

Soil pH

The pH of the soil holds a major stake in the rate of decomposition as it affects the presence of microbes. Microbes are essential for decomposition. Fungi survive in an acidic environment, whereas Bacteria do not survive in an environment with a pH above 6, so the pH of soil affects the rate of decomposition.

Moisture

As the moisture content increases the rate of decomposition decreases. the water particles fill up the empty air gaps present in the soil thus slowing down the decomposition.

Oxygen levels

The microbes which act as decomposers need oxygen to survive and hence higher oxygen eleven means higher decomposition.  

FAQs on Decomposition

Q1: Define Decomposition.

Answer:

Decomposition can be defined as the process of breaking down complex organic substances into smaller simpler particles by various microorganisms which can be later used. The term decomposition means the breaking down of particles or ” break down”.

Q2: What are the types of decomposition processes?

Answer:

The types of decomposition processes are biotic and abiotic decomposition.

Q3: What is detritus?

Answer:

In the process of decomposition, the dead organic raw material is referred to as detritus. 

Q4: List the factors affecting decomposition.

Answer:

Some of the factors affecting decomposition are Litter Quality, Aeration(oxygen content), pH of the soil, Moisture content of soil etc.