Question

What do you mean by stone cancer? How and why does it occur?

Answer 1

Hint: Stone cancer is a side effect of acid rain where old monuments get either eroded or change their colour due to acid rain. For example, the Taj Mahal is turning yellow due to acid rain.

Complete step by step answer:
Sulphur dioxide in the atmosphere, when mixed with water vapour of clouds, forms acid rain. The acid rain when comes down on earth in the form of rainwater severely affects the buildings, sculptures, monuments, etc. This phenomenon of stone cancer is marked by discoloration and deterioration.
For example, in India, the famous Taj Mahal has developed blackening & yellowing due to the acid rain. The root cause of these acid rain is the pollutants released by the Mathura Refinery.

Additional Information:
Acid rain is an environmental condition that describes any form of precipitation that has acidic components, such as sulfuric or nitric acid. They can fall to the earth from the atmosphere either in wet or dry forms that include rain, snow, fog, dust.
The major sources of sulphur dioxide and oxides of nitrogen in the atmosphere are:
a. Burning of fossil fuels to generate energy. For example, 2/3rd of sulphur dioxide and 1/4th of oxides of nitrogen in the atmosphere is produced from electric power generators.
b. Vehicles and heavy equipment.
c. Oil refinery.

Buffering Capacity- Buffering capacity depends on the soil composition, thickness, and mineral content. As a result of many forests, the water reservoir resists the impact of acid rain & neutralizes the effect of acid rain.
Episodic Acidification- Episodic acidification is caused by melting snow and heavy rain downpours. The water reservoirs that normally do not have a high level of acidity experience effects of acid rain due to the melting snow or rainfall as the soil can’t buffer it. This acute condition of hyperacidity causes temporary stress & death of a variety of organisms.

Note: Acid rain is a major problem across the globe. It severely affects life in all forms of the ecosystem. An ecosystem is a region where the biotic component (plants, animals, and other organisms) of the environment interact with abiotic components (air, water, and soil) to sustain life. In an ecosystem, everything is connected. So, if one component is hampered the other will also get affected.
Effects of acid rain are on:
a. Fish and Wildlife
b. Plants and Trees
c. Materials like monuments, buildings, etc.
d. Visibility
e. Human Health