Effects of Acid Rain
Effects on human health: Humans are vulnerable to acid rain. Thousands of premature deaths are caused by sulphate laden air due to acid rain annually. Millions of people are drinking water with high lead levels. Lead (Pb) is one of the factors responsible for high blood-pressure and heart attacks in adults and brain damage in children. Harmful effects of acid rain on human are Chronic bronchitis, pulmonary emphysema, (related to lungs) cancer.
Damages soil: Acid rain leach out soil nutrients, adversely affects the properties of soil, causes damage to soil fertility, damages vegetation including cropland and forests, makes the leaves of plants yellow and brown. This is how acid rain impacts the productivity of forests, grasslands and crops.
Damage to aquatic ecosystems: Acidification can be natural as well as anthropogenic. It kills plankton, fish and adversely affects productivity of aquatic ecosystems.
Acidity in soil and water due to acid rain leads to increase in dissolved metals especially aluminium. Aluminium affects the grills of fish. On account of respiratory failure they die due to heavy metals as Al (Aluminium), Zn (Zinc), Mn (Manganese), Cd (Cadmium), Pb (Lead), Cu (Copper) added in water increases acidity beyond permissible limits.
Damage to ecosystem (forest): It is difficult to have a quantitative effect of acid rain on ecosystem. However, intense sulphur dioxide pollution around smelters is known to cause death of many kinds of trees and other vegetation.
The typical impact of Acid Rain are as follow:
- Yellowing and browning of needles and leaves.
- Decreased annual increment.
- Death of herbaceous vegetation.
- Active shedding of needles and leaves while still green.
- Death and diseased trees.
Effects on microorganisms and wildlife: Proliferation of microbial species governed by pH value. There are three pH value of water: acidic, neutral and alkaline. Many bacteria and protozoa have pH optima near neutrality; most fungi prefer an acid environment and many blue-green bacteria prefer an alkaline environment. So pH determines whether any microbial species can proliferate in a particular environment and the rate at which it can reproduce.
Effect on Wildlife: The impact of Acid Rain is also seen in wildlife. Acid rain carry metals bound in soil and sediment released into the aquatic environment. The toxic substances so discharged are ingested by wildlife, like birds that feed in such environment. This is a direct effect of acid rain. The indirect effects of acid rain are loss of food and habitat resources. The elimination of fish from lake during the breeding season is one example. Fish population has decreased tremendously. The fish-less area (lakes) are now fish grave-yards. Many bacteria and blue algae are killed due to acidification, thus disrupting ecological balance.
