Effects of Acid Rain

 

Effects of Acid Rain

After studying the Hubbard Brook Forest and other areas, researchers found several important effects of acid deposition on both natural and man-made environments. Aquatic settings are the most clearly affected by acid deposition, however, because acidic precipitation falls directly into them. Both dry and wet deposition also runs off from forests, fields, and roads and flows into lakes, rivers, and streams.

As this acidic liquid flows into larger bodies of water, it is diluted. Howvever, over time, acids can accrue and lower the overall pH of the body of water. Acid deposition also causes clay soils to release aluminum and magnesium, further lowering the pH in some areas. If the pH of a lake drops below 4.8, its plants and animals risk death. It is estimated that around 50,000 lakes in the United States and Canada have a pH below normal (about 5.3 for water). Several hundred of these have a pH too low to support any aquatic life.

Aside from aquatic bodies, acid deposition can significantly affect forests. As acid rain falls on trees, it can make them lose their leaves, damage their bark, and stunt their growth. By damaging these parts of the tree, it makes them vulnerable to disease, extreme weather, and insects. Acid falling on a forest’s soil is also harmful because it disrupts soil nutrients, kills microorganisms in the soil, and can sometimes cause a calcium deficiency. Trees at high altitudes are also susceptible to problems induced by acidic cloud cover as the moisture in the clouds blankets them.

Damage to forests by acid rain is seen all over the world, but the most advanced cases are in Eastern Europe. It’s estimated that in Germany and Poland, half of the forests are damaged, while 30 percent in Switzerland have been affected.

Finally, acid deposition also has an effect on architecture and art because of its ability to corrode certain materials. As acid lands on buildings (especially those constructed with limestone), it reacts with minerals in the stones, sometimes causing them to disintegrate and wash away. Acid deposition can also cause concrete to deteriorate, and it can corrode modern buildings, cars, railroad tracks, airplanes, steel bridges, and pipes above and below ground.

What's Being Done?

Because of these problems and the adverse effects of air pollution has on human health, a number of steps are being taken to reduce sulfur and nitrogen emissions. Most notably, many governments are now requiring energy producers to clean smokestacks with scrubbers that trap pollutants before they are released into the atmosphere and to reduce car emissions with catalytic converters. Additionally, alternative energy sources are gaining more prominence and funding is being put toward the restoration of ecosystems damaged by acid rain worldwide.