2017 · Q93
Which of the following are the necessary conditions for the growth of coral reefs?
- 1Photic conditions
- 2Clean and sediment free water
- 3Sea salinity of 6%
- 4Tropical sea water with temperature of 20°C to 21°C
Select the correct answer using the code given below:
indian-world-geographyoceanography
- A1, 2 and 4 only
- B2 and 4 only
- C1 and 3 only
- D1, 2, 3 and 4
Explanation
Corals need sunlight (photic conditions), clean sediment-free water, and warm tropical water around 20–21°C – statements 1, 2 and 4 are correct. Statement 3 is wrong: normal sea salinity is about 3.5 per cent (35 ppt), not 6 per cent. Hence only 1, 2 and 4 are correct, giving (A).