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The given graphs shows the productivity ...

The given graphs shows the productivity of an aquatic ecosystem measured in terms of dissolved oxygen produced and consumed by green plants and photosynthetic algae where PS=photosynthesis and R=respiration.

A

PS will be increase, R will be decreased

B

PS will be decreased, R will be increased.

C

PS and R will not change.

D

PS+R will increase.

Text Solution

Verified by Experts

The correct Answer is:
D
During photosynthesis, green plants produce oxygen which leads to increase in dissolved oxygen in an aquatic ecosystem. Respiration uses oxygen and hence causes decrease in dissolved oxygen. The excess growth of planktonic algae that causes colouration of water is called algal bloom. The increased growth in photosynthetic algae will lead to more photosynthesis which will increase PS+ R ultimately.
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NCERT FINGERTIPS-ECOSYSTEM-Ecosystem
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  2. The graph given below shows the variations in the population of produc...

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  3. The given graphs shows the productivity of an aquatic ecosystem measur...

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  4. Decomposers like fungi and bacteria are

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  5. The process of mineralisation by microorganisms helps in the relase of

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  6. Productivity is the rate of production of biomass expressed in terms o...

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  7. An inverted pyramid of biomass can be found in which ecosystem?

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  8. Which of the pyramid of biomass can be found in which ecosystem?

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  9. Which of the following ecosystems is most productive in terms of net p...

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  10. Pyramid of numbers is

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  11. Approximately how much of the solar energy that falls on the leaves of...

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  12. Among the following where do you think the process of decomposition wo...

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  13. How much of the net primary productivity of a terrestrial ecosystem is...

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  14. During the process of ecological succession, the changes that take pla...

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  15. Climax community is in a state of

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  16. Among the following biogeochemical cycles, which one does not have los...

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  17. The sequence of communities of primary succession in water is

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  18. The reservoir for the gaseous type of biogeochemical cycle exists in

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  19. If the carbon atoms fixed by producers already have passed through thr...

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  20. Which of the following types of ecosystem is expected in an area where...

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