Which one of the following organisms are indicator of SO2 pollution of air?

Explanation

Let's explain each option individually: a) Mosses: Mosses are sensitive to air pollution, including sulfur dioxide (SO2) pollution, but they are not the primary indicator species for SO2 pollution. While mosses can be affected by air pollutants and can show signs of stress or damage in polluted environments, their response to SO2 pollution is not as specific or pronounced as some other organisms, like lichens. b) Lichens: This option is correct. Lichens are excellent indicators of SO2 pollution in the air. Lichens are unique organisms composed of a symbiotic association between a fungus and an alga or a cyanobacterium. They are highly sensitive to air pollution, particularly sulfur dioxide (SO2) and other sulfur-containing compounds. Lichens are efficient at absorbing and accumulating airborne pollutants, including SO2, from the atmosphere. As a result, they are particularly useful as bioindicators in air quality monitoring programs. The presence, absence, or health of certain lichen species in a given area can provide valuable information about the level of air pollution, especially SO2 pollution. c) Mushrooms: Mushrooms, as fruiting bodies of fungi, do not directly serve as indicators of SO2 pollution. However, fungi, including mushrooms, can be impacted by air pollution in general, depending on the type and severity of pollutants in the environment. d) Puffballs: Puffballs are a type of fungi that produce spores inside an enclosed fruiting body. Similar to mushrooms, puffballs do not directly function as indicators of SO2 pollution. While fungi, including puffballs, can be influenced by air quality, they are not specific indicators of SO2 pollution. In summary, the correct answer is b) Lichens. Lichens are excellent indicators of SO2 pollution in the air due to their high sensitivity to sulfur dioxide and their ability to accumulate airborne pollutants, making them valuable bioindicators in air quality monitoring programs. The other options (mosses, mushrooms, and puffballs) may also be influenced by air pollution but are not as specific or reliable indicators of SO2 pollution as lichens.