Q. Consider the following statements regarding “eutrophication”:
1.It is primarily caused by the leaching of phosphate and – or nitrate containing fertilizers from agricultural lands into lakes or rivers.
2.The growth of green algae which we see in the lake surface layer is the physical identification of a Eutrophication.
Which of the statements given above is/are correct?

[A] 1 only

[B] 2 only

[C] Both 1 and 2

[D] Neither 1 nor 2

Answer: C
Notes:

Explanation: EUTROPHICATION:

  • Greek word – Eutrophia means adequate & healthy nutrition.
  • Eutrophication is a syndrome of ecosystem, response to the addition of artificial or natural nutrients such as nitrates and phosphates through fertilizer, sewage, etc that fertilize the aquatic ecosystem.
  • It is primarily caused by the leaching of phosphate and – or nitrate containing fertilisers from agricultural lands into lakes or rivers.
  • The growth of green algae which we see in the lake surface layer is the physical identification of a Eutrophication.
  • Some algae and blue-green bacteria thrive on the excess ions and a population explosion covers almost entire surface layer is known as algal bloom. This growth is unsustainable, however.
  • As Algal Bloom covers the surface layer, it restricts the penetration of sunlight. Diffusion of gas from atom
  • Oxygen is required by all respiring animals in the water and it is replenished by diffusion and photosynthesis of green plants.

Source: SHANKAR IAS Environment