Maharashtra State PSC Model Paper 2

The correct answer is 1 and 2 only.

• Eutrophication is the natural ageing of a lake by the biological enrichment of its water.
  • With time, streams draining into the lake introduce nutrients such as nitrogen and phosphorus, which encourage the growth of aquatic organisms.
  • As the lake’s fertility increases, plant and animal life burgeons, and organic remains begin to be deposited on the lake bottom.
  • Over the centuries, as silt and organic debris pile up, the lake grows shallower and warmer, with warm-water organisms supplanting those that thrive in a cold environment.
  • Marsh plants take root in the shallows and begin to fill in the original lake basin.
  • Eventually, the lake gives way to large masses of floating plants (bog), finally converting into the land.
  • Hence, statements 1 and 2 are correct.
• Chlorofluorocarbons do not play any role in Eutrophication.
  • Hence, statement 3 is not correct.