English
Karnataka Board PUCPUC Science 2nd PUC Class 12

Justify the following statement in terms of ecosystem dynamics. “Nature tends to increase the gross primary productivity, while man tends to increase the net primary productivity”.

Advertisements
Advertisements

Question

Justify the following statement in terms of ecosystem dynamics. “Nature tends to increase the gross primary productivity, while man tends to increase the net primary productivity”.

Long Answer
Advertisements

Solution

Rate of production of organic matter in an ecosystem is called Gross Primary Productivity (GPP). When we subtract the respiratory losses (R) from GPP, we get Net Primary Productivity (NPP). 

Nature provides various biotic and abiotic factors to enhance the rate of Gross Primary Productivity. Hence, it can be said that nature tends to increase the gross primary productivity. 

But human beings need to make optimum utilization of the biomass produced. This is achieved in various ways; like harvesting the crop at the right time and plucking the fruits at the right time. If fruits will be left on the tree for a longer time, it will result in higher respiratory losses. A higher respiratory loss will reduce NPP. By plucking the fruits at the right time, man tries to increase the net primary productivity. 

shaalaa.com
  Is there an error in this question or solution?
Chapter 14: Ecosystem - LONG ANSWER [Page 104]

APPEARS IN

NCERT Exemplar Biology Exemplar [English] Class 12
Chapter 14 Ecosystem
LONG ANSWER | Q 2. | Page 104

Video TutorialsVIEW ALL [1]

RELATED QUESTIONS

Why does primary productivity vary in different types of ecosystems?


Explain what does the equation given below show:

NPP = GPP – R


Secondary productivity is rote of formation of new organic matter by ______.


How much of the net primary productively of a terrestrial ecosystem is eaten and digested by herbivores?


Which one of the following ecosystem has the highest annual net productivity?


If A = Gross primary productivity, B = Net primary productivity and C = Respiration losses, then what will be the correct relation between them?


Productivity is the rate of production of biomass expressed in terms of ______.


Which of the following ecosystems is most productive in terms of net primary production?


Justify the pitcher plant as a producer.


Why are oceans least productive?


Primary productivity varies from ecosystem to ecosystem. Explain?


The primary productivity in an ecosystem is expressed as ______.

  1. gm-2 yr-1
  2. gm-2 yr
  3. Kcal m-2 yr-1
  4. Kcal m-2

Use the information provided in the table given below to answer the following questions:

Tropic level Net Production(KJm-2y-1) Respiration (KJm-2y-1)
Top Carnivore 50 35
Carnivores 420 378
Herbivores 4490 4041
Producers 45000 40,367
  1. Calculate the gross primary productivity.
  2. Analyze the trend in the Net Production from Producers to Top Carnivore. Give a reason for your observation.

In an ecosystem if the Net Primary Productivity (NPP) of first trophic level is 100x(kcal m−2) yr−1, what would be the GPP (Gross Primary Productivity) of the third trophic level of the same ecosystem?


Primary productivity in an ecosystem refers to the rate of generation of ______.


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×