Question

The rate of decomposition is faster in the ecosystem due to following factors EXCEPT:

• A. Detritus rich in sugars
• B. Warm and moist environment
• C. Presence of aerobic soil microbes
• D. Detritus richer in lignin and chitin

Answer 1

The correct option is D Detritus richer in lignin and chitin

Decomposition is the breakdown of complex organic materials present in dead remains of plants and animals (detritus) into simple inorganic compounds by decomposers (microbes such as bacteria and fungi).

Decomposition largely occurs in the presence of oxygen. Aerobic soil microbes utilize oxygen in decomposing the organic matter. Hence, the rate of decomposition is faster in the presence of aerobic soil microbes.

The rate at which decomposition occurs is dependent on multiple factors such as

• Chemical composition of the detritus - the presence of polymers such as lignin and chitin in the detritus slows down the decomposition process. Presence of nitrogen and water-soluble sugars in the detritus can speed up the rate of decomposition.
• Environmental temperature - a warm temperature favours the rate of decomposition whereas low temperatures slow down the rate of decomposition.
• Soil moisture - rate of decomposition is higher when the soil is moist.

Hence, the correct answer is option d.