Question

Read the following statements and find out the incorrect statement(s).

• A. In a particular climatic condition, decomposition rate is slower if detritus is rich in nitrogen and water soluble compounds like sugars.
• B. All of the above.
• C. Warm and moist environments inhibit decomposition.
  
• D. Rate of decomposition is quicker if detritus is rich in lignin and chitin.

Answer 1

The correct option is B All of the above.

Introduction to decomposition :
Decomposition is the process of breakdown of complex organic materials present in the dead decaying organic matter into simple inorganic compounds such as carbon dioxide, water and mineral nutrients. It is carried out by microscopic organisms such as bacteria, fungi, etc.

Factors affecting the rate of decomposition are: -
● Chemical composition of detritus
● Soil pH
● Temperature
● Moisture
● Soil aeration

Option-A
The rate of decomposition depends upon the chemical composition of the detritus. In a particular climate having constant temperature and soil moisture, rich nitrogen content and presence of water-soluble sugars helps to increase the rate of decomposition.
Thus, the statement in option A is incorrect.

Option B
The rate of decomposition is affected by the chemical composition of the detritus. The presence of large complex polymers such as lignin and chitin in the detritus slows down the decomposition process.
Thus, the statement in option B is incorrect.

Option C
Temperature is a climatic factor that affects the rate of decomposition. A temperature of ${25}^{o}C$ is optimum for the growth and activity of decomposing microbes under proper conditions of moisture and aeration.
High moisture content in the soil also promotes the growth of the microbes and hence the rate of decomposition also increases.
Thus warm and moist environments help to promote the decomposition reaction.
Thus, the statement in option C is incorrect.

Final answer :
(D) All of the above.