The term ‘acid rain’ refers to the deposition of wet or dry acidic materials from the atmosphere on the earth’s surface.
Sulphuric acid and Nitric acid is considered as the principal agents responsible for acid rain.
Smokes emitted from the industries are the major source of sulphur dioxide whereas smokes emitted from the motor vehicle is the major source of nitrogen oxide.
These emissions mixed with atmospheric moisture to form the sulphuric acid and nitric acids which, sooner or later precipitate on earth in various form.
Acidity is measured on a pH scale based on the relative concentration of hydrogen ions.
The scale ranges from 0 to 14, where the lower end represents extreme acidity and the upper end extreme alkalinity.
Acid rain is associated with various forms of precipitation.
The long term effects of acid precipitation on human health and agricultural production have not yet been ascertained precisely.
The Eco-system of a stream or lake may be severely affected when its pH falls below 5.
Total biomass in such systems is reduced from two to ten times because few organisms can tolerate acid.
The diversity of species also decreases.
The most severe effect of acidification is on fish.
Acidic conditions affect the reproductive capabilities of fish, resulting in a slow decline of fish population.
Buildings and monuments are being destroyed because acid deposition accelerated erosion capacity.