Acid Rain On Water Essay, Research Paper

The effects of acid rain are most clearly seen in the aquatic, or water,

environments, such as streams, lakes, and marshes. Acid rain flows to streams,

lakes, and marshes after falling on forests, fields, buildings, and roads. Acid

rain also falls directly on aquatic habitats. Most lakes and streams have a pH

between 6 and 8. However, some lakes are naturally acidic even without the

effects of acid rain. Lakes and streams become acidic (pH value goes down) when

the water itself and its surrounding soil cannot buffer the acid rain enough to

neutralize it. In areas like the Northeastern United States where soil buffering

is poor, some lakes now have a pH value of less than 5. One of the most acidic

lakes reported is Little Echo Pond in Franklin, New York. Little Echo Pond has a

pH of 4.2. Lakes and streams in the western United States are usually not

acidic. Because of differences in emissions and wind patterns, levels of acid

deposition are generally lower in the western United States than in the eastern

United States. This chart shows that not all fish, shellfish, or their food

insects can tolerate the same amount of acid: Generally, the young of most

species are more sensitive than adults. 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. 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. 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. Some acid lakes have no fish. At pH 5, most fish eggs cannot

hatch. At lower pH levels, some adult fish die. Toxic substances like aluminum

that wash into the water from the soil may also kill fish. 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, fish eat other fish and also other plants and animals that live in the

lake or stream. If acid rain causes the loss of acid-sensitive plants and

animals, then fish that rely on these organisms for food may also be affected.