Question

Consider the following statements regarding Decomposers.

1. By the process of leaching, water-soluble inorganic nutrients go down into the soil horizon and get precipitated as unavailable salts. 

2. Humification leads to the accumulation of a dark-coloured amorphous substance called humus that is highly resistant to microbial action and undergoes decomposition at an extremely slow rate. 

Which of the statements given above is/are correct?

1. 1 only
2. 2 only
3. Both 1 and 2
4. Neither 1 nor 2

Answer 1

Correct Answer - Option 3 : Both 1 and 2

The correct answer is Both 1 and 2.

• Decomposers break down complex organic matter into inorganic substances like carbon dioxide, water, and nutrients and the process is called decomposition.
• Dead plant remains such as leaves, bark, flowers, and dead remains of animals, including faecal matter, constitute detritus, which is the raw material for decomposition.
• The important steps in the process of decomposition are fragmentation, leaching, catabolism, humification, and mineralization.
• Detritivores (e.g. earthworms) break down detritus into smaller particles. This process is called fragmentation.
• By the process of leaching, water-soluble inorganic nutrients go down into the soil horizon and get precipitated as unavailable salts. Hence, Statement 1 is correct.
• Bacterial and fungal enzymes degrade detritus into simpler inorganic substances. This process is called catabolism.
• It is important to note that all the above steps in decomposition operate simultaneously on the detritus.
• Humification and mineralization occur during decomposition in the soil.
• Humification leads to the accumulation of a dark-coloured amorphous substance called humus that is highly resistant to microbial action and undergoes decomposition at an extremely slow rate. Hence, Statement 2 is correct.
  • Being colloidal in nature it serves as a reservoir of nutrients.
  • The hummus is further degraded by some microbes and the release of inorganic nutrients occurs by the process known as mineralization.