Question

In relation to Gross primary productivity and Net primary productivity of an ecosystem. Which one of the following statements is correct

• A. Gross primary productivity and Net primary productivity are one and same.
• B. There is no relationship between Gross primary productivity and Net primaryproductivity
• C. Gross primary productivity is always less than Net primary productivity.
• D. Gross primary productivity is always more than Net primary productivity.
  

Answer 1

The correct option is D

Gross primary productivity is always more than Net primary productivity.

The correct option is D.

Explanation for Correct option:

1. The entire amount of biomass generated by producers is known as gross primary productivity.
2. After being used for respiration and lost as heat, net primary productivity is the amount of biomass ingested by producers that can be passed on to the next trophic level.
3. The rate of generation of organic matter during photosynthesis determines an ecosystem's gross primary productivity.
4. Plant respiration causes some of this organic stuff to be lost.
5. Net primary productivity is the remaining primary productivity.

Explanation for Incorrect option:

Option A:

1. The amount of carbon fixed during photosynthesis by all producers in the ecosystem is referred to as gross primary productivity.
2. NPP can be defined as the rate at which biomass or energy accumulates.
3. The energy used in metabolic activities like breathing is not included in gross production (GPP)
   

Option B:

1. Gross primary productivity refers to the rate at which organic matter is produced through photosynthesis, while net primary productivity refers to the total amount of biomass accessible for heterotrophic use.
2. As a result, productivity is equal to the sum of gross primary and net primary productivity.
   

Option C:

1. The overall rate of energy capture is referred to as gross productivity.
2. It can't be a lower than Net primary productivity
   

Final answer: Gross Primary productivity is always more than Net primary productivity.