EFFECTS OF ACID RAIN

Acid rain causes problems in almost every aspect of the environment. Acid rain can have a devastating effect on aquatic life, crops, forests, buildings, and also human life.

A) The human Health

The harm to people from acid rain is not direct. The pollutants that cause acid rain (sulfur dioxide (SO2) and nitrogen oxides (NOx)) also damage human health. These gases interact in the atmosphere to form fine sulfate and nitrate particles that are inhaled into people's lungs causing  increased illness and premature death.

Nitrogen oxides  react with volatile organic compounds and form ozone. Ozone impacts on human health include a number of morbidity and mortality risks associated with lung inflammation, including lung cancer, asthma, bronchitis and emphysema.

Sulfates and nitrates that form in the atmosphere from sulfur dioxide (SO2) and nitrogen oxides (NOx) emissions contribute to visibility impairment. Sulfate particles account for 50 to 70 percent of the visibility reduction.

B) The Human Environment.

The acid also eats through the pipes that channel water to the lakes. Far more insidious are the increasing incidents of attributed to breathing in the tiny particles of sulphur and other pollutants. Many people drink water everyday that is laced with these harmful chemicals without even knowing it.

Acid rain and the dry deposition of acidic particles contribute to the corrosion of metals (such as bronze) and the deterioration of paint and stone (such as marble and limestone). These effects seriously reduce the value to society of buildings, bridges, cultural objects (such as statues, monuments, and tombstones), and cars.

C) The Forests

Acid rain causes slower growth, injury, or death of forests. Acid rain has been implicated in forest and soil degradation. The impacts of acid rain on trees occur due to the combined effects of acid rain and other environmental stressors. A spring shower in the forest washes leaves and falls through the trees to the forest floor below. That soil may neutralize some or all of the acidity of the acid rainwater. This ability is called buffering capacity. The ability of forest soils to resist, or buffer, acidity depends on the thickness and composition of the soil, as well as the type of bedrock beneath the forest floor.

Acid rain weaken trees by damaging their leaves, limiting the nutrients available to them, or exposing them to toxic substances slowly released from the soil. Acidic water dissolves the nutrients and helpful minerals in the soil and then washes them away before trees and other plants can use them to grow. At the same time, acid rain causes the release of substances that are toxic to trees and plants, such as aluminum, into the soil.

Forests in high mountain regions often are exposed to greater amounts of acid than other forests because they tend to be surrounded by acidic clouds and fog that are more acidic than rainfall. When leaves are frequently bathed in this acid fog, essential nutrients in their leaves and needles are stripped away.

D) The Lakes and Streams

Forests aren’t alone in the devastation. It has also been found that twenty thousand lakes have been acidified through the changes in the groundwater.

When acid rain falls into water it is mixed in with the normal water and causes the pH of the entire body to be raised.  Measurements on the pH scale rise exponentially, thus, a lake with a pH of 4 is ten times as acidic as a lake with a pH of 5, and a lake with a pH of 3 is 100 times as acidic.

Acid Rain has been known to reach the acidity of pH 2, this is a drastic change as normal rain is average pH 5.6.

Salting (dropping salt, chalk, or limestone into lakes and streams) is a done to neutralize the water and counteracting the effects of the acid rain. This involves literally tons of salt. This is only a temporary solution, as putting salt into the water will not stop the acid from coming, it just neutralizes what is already there.

E)  Fish and Other Aquatic Organisms

Acid rain causes a cascade of effects that harm or kill individual fish, reduce fish population numbers, completely eliminate fish species from a waterbody, and decrease biodiversity. As acid rain flows through soils in a watershed, aluminum is released from soils into the lakes and streams located in that watershed. So, as pH in a lake or stream decreases, aluminum levels increase. Both low pH and increased aluminum levels are directly toxic to fish. In addition, low pH and increased aluminum levels cause chronic stress that may not kill individual fish, but leads to lower body weight and smaller size and makes fish less able to compete for food and habitat.

           

Some types of plants and animals are able to tolerate acidic waters. Others, however, are acid-sensitive and will be lost as the pH declines. Generally, the young of most species are more sensitive to environmental conditions than adults. At pH 5, most fish eggs cannot hatch. At lower pH levels, some adult fish die. Some acid lakes have no fish. The chart below shows that not all fish, shellfish, or the insects that they eat can tolerate the same amount of acid; for example, frogs can tolerate water that is more acidic (has lower pH) than trout.

F)         The Ecosystems

Together, biological organisms and the environment in which they live are called an ecosystem. The plants and animals living within an ecosystem are highly interdependent. For example, frogs may tolerate relatively high levels of acidity, but if they eat insects like the mayfly, they may be affected because part of their food supply may disappear. Because of the connections between the many fish, plants, and other organisms living in an aquatic ecosystem, changes in pH or aluminum levels affect biodiversity as well. Thus, as lakes and streams become more acidic, the numbers and types of fish and other aquatic plants and animals that live in these waters decrease

G)        Soil

Acid Rain reacts to different types of soil and rocks in two ways: 1) Acid rain will dissolve alkaline rocks and soil, or will neutralize the alkalinity. 2) Acid rain will increase the acidity of already acidic rocks and soil, such as granite, or the soil which results from corroded granite.