EVERYDAY SCIENCE

Detailed explanation-1: -Bioindicators are used to monitor the protection of the natural environment in the surroundings. Lichens are the most accurate indicators of sulfur dioxide in the atmosphere. Sulfur dioxide dissolves in rainwater, causing lichen damage and preventing it from growing.

Detailed explanation-2: -If air is polluted with sulphur dioxide, then lichens will die in that particular environment. Since the era of industrialization, many species of lichens have gone extinct. Due to this property, lichens are considered to be the indicators of the air pollution.

Detailed explanation-3: -Presence of sulphur dioxide in the atmosphere inhibits the growth of lichens. Therefore, they are used as an indicator to detect the presence of sulphur dioxide. Presence of sulphur dioxide reduces the rate of growth of lichens because lichens are highly sensitive towards sulphur dioxide.

Detailed explanation-4: -Lichens as Bio-Indicators Lichens are sensitive to atmospheric pollution such as nitrogen (N) because they receive all their nutrients and water from wet and dry atmospheric deposition (fall out). Nitrogen deposition can increase the load of nutrients.

Detailed explanation-5: -This leads to accumulation of sulphur in lichen. This enhances sulphur dioxide concentration affects the algal partner because sulphur dioxide is responsible for breaking down of chlorophyll and photosynthesis is inhibited. That’s why lichen acts as an indicator for