Question

Use of lichens in case of pollution is

• A. Treatment of pollutant water
• B. Bioindicators of pollution
• C. Promote pollution
• D. Lichens have no relation with pollution

Answer 1

Answer: (B)

Bioindicators of pollution

Lichen represents the symbiotic association between the algae and fungi. These absorb their mineral nutrients from the atmospheric moisture rather than the soil. So, when the air is contaminated with the sulphur oxides, they show extreme sensitivity to the toxic gas. Their existence is threatened by the oxides of sulphur in the air. The disappearance of the lichen, when exposed to the sulphur oxide, is used as bioindicator of the sulphur pollution in the air.

So, the correct answer is 'Bioindicators of pollution'