RAS question
Which of the following correctly describes 'Phytoremediation'?
Correct answer: (A) Using plants to absorb and remove contaminants from soil and water.
Phytoremediation is the use of living plants to absorb, contain, remove, or degrade contaminants from polluted soil, water, and air.
Explanation
Phytoremediation is a plant-based method of remediation, not a chemical or fire-based clean-up technique. It uses specific plants to extract, contain, or degrade pollutants such as heavy metals, pesticides, and solvents from contaminated soil, water, and air. U.S. Environmental Protection Agency describes phytoremediation techniques as using living plants as an environmentally friendly approach for cleaning contaminated soil and groundwater, and plant systems can contain and degrade contaminants. That is why option A is the best description. It captures the essential feature of the process: plants are the active clean-up medium, and the target is contamination in environmental matrices such as soil and water.
Why the other options are wrong
- (B) Using chemicals to clean contaminated soil is chemical remediation, whereas phytoremediation depends on plants as the clean-up medium.
- (C) Using animals for pest control describes biological control, not the use of plants to remove or degrade environmental contaminants.
- (D) Using fire to sterilise land is a heat-based sterilisation approach, not a plant-based remediation method for pollutants.
Concept
This tests environmental biotechnology under Science and Technology, especially the distinction between biological remediation methods and other clean-up techniques. It recurs in RAS because pollution control terms are often asked as definition-based applied science questions.