Question

Which of the following are the reliable indicators of air pollutants, particularly sulphur dioxide?

• A. Ferns and cycas
• B. Neem and Eichhornia
• C. Lichens and mosses
• D. Green algae and aquatic liverworts

Answer 1

The correct option is C Lichens and mosses

Mosses and lichens are reliable indicators of air pollutants, particularly sulphur dioxide because of their underdeveloped root system. Both are non-vascular plants and hence they accumulate trace elements from the atmosphere. This way they are able to accumulate and retain air pollutants. Thus do not grow in areas where there is Sulphur dioxide pollution. If you see one of these on your walk, it probably means that coal has not been burnt in the area for some time.

Thus, lichens and mosses are good indicators of air pollution.