Q. With reference to Water Hyacinth, consider the following statements;
1.It is an indigenous species of aquatic weed.
2.The plant has the ability to trap and remove toxic metabolites and harmful heavy metals from water.
3.It is associated with the depletion of dissolved oxygen in the water.
Select the correct answer using the code given below:

[A] 1 only

[B] 2 and 3 only

[C] 1 and 3 only

[D] 1, 2 and 3

Answer: B
Notes:

Statement 1 is incorrect: It is not an indigenous species but was introduced to India during the British colonial rule as an ornamental aquatic plant from South America.

Statement 2 is correct: The plant is a good phytoremediation species, suggesting it has the ability to trap and remove toxic metabolites and harmful heavy metals from water. But more research needs to be conducted to find a suitable use for the notorious weed.

Statement 3 is correct: Water hyacinth is considered invasive because it grows rapidly and can form thick layers over the water. These mats shade out the other aquatic plants. Eventually, these shaded plants die and decay. The decaying process depletes the amount of dissolved oxygen in the water. As oxygen levels decline, many fish are unable to survive. Often the waters below water hyacinth masses become devoid of life.

Source: DTE