The Glass Menagerie
Essay by 24 • March 17, 2011 • 2,342 Words (10 Pages) • 1,142 Views
I. INTRODUCTION
Acid rain or acid deposition is a form of precipitation (rain, snow, sleet, or hail) containing high levels of sulfuric or nitric acids (pH below 5.5-5.6). It is produced when sulfur dioxide and various nitrogen oxides combine with atmospheric moisture, acid rain can contaminate drinking water, damage vegetation and aquatic life, and erode buildings and monuments. Automobile exhausts and the burning of high-sulfur industrial fuels are thought to be the main causes, but natural sources, such as volcanic gases and forest fires, may also be significant. It has been a more and more serious problem since the 1950s, for the most part in the Northern Eastern United States, Canada, and Western Europe, mainly in Scandinavia.
II. DEFINITION OF THE PRBLEM
The purpose of the experiment was to determine the of acid effect rain on wheat grass. I became interested in this idea because acid rain has develop into a big problem in the United States, Canada, Western Europe, Scandinavia and many other countries. The information gained from this experiment would help out factory owners and operators that acid rain is harmful to forests, crops, and wildlife. They should do something to keep the air cleaner. Also car manufactures should make cars that run on something other than gasoline, which would also keep our air cleaner and would help reduce acid rain.
III. Literature Review
When two pollutants called Sulfur dioxide and Nitrogen oxide, they form acid
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rain. Each year the global atmosphere is receiving 20 billion tons of carbon dioxide, 130 million tons of sulfur dioxide, 97 million tons of hydrocarbs, 53 million tons of Nitrogen Oxides, more than 3 million tons of mercury, lead, zinc, nickel, arsenic, and other toxic metals. "Acid rain is a broad term used to describe several ways that acids fall out of the atmosphere. A more precise term is acid deposition, which has two parts: wet and dry. Wet deposition refers to acidic rain, fog, and snow. As this acidic water flows over and through the ground, it affects a variety of plants and animals. The strength of the effects depend on many factors, including how acidic the water is, the chemistry and buffering capacity of the soils involved, and the types of fish, trees, and other living things that rely on the water. Dry deposition refers to acidic gases and particles. About half of the acidity in the atmosphere falls back to earth through dry deposition. The wind blows these acidic particles and gases onto buildings, cars, homes, and trees. Dry deposited gases and particles can also be washed from trees and other surfaces by rainstorms. When that happens, the runoff water adds those acids to the acid rain, making the combination more acidic than the falling rain alone. Prevailing winds blow the compounds that cause both wet and dry acid deposition across state and national borders, and sometimes over hundreds of miles." "Acid rain causes acidification of lakes and streams and contributes to damage of trees at high elevations (for example, red spruce trees above 2,000 feet) and many sensitive forest soils. In addition, acid rain accelerates the decay of building materials and paints,
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including irreplaceable buildings, statues, and sculptures that are part of our nation's cultural heritage. Prior to falling to the earth, SO2 and NOx gases and their particulate matter derivatives, sulfates and nitrates, contribute to visibility degradation and harm public health." ("What is Acid Rain and What Causes It?" 9) " It appears that interactions of acid precipitation and gaseous pollutants could have a damaging effect on plants. The experts are quick to point out, however, that there are still many uncertainties. Only the potential for negative impacts has been determined. According to the OTA report, regions most likely to suffer negatives effects from a combination of gaseous pollutants and acid ran would be in the commercial forests of the Mississippi River Valley, forests of the Appalachian Mountains, and agriculture and forests lands of the Ohio River Valley." (Gay, 1983, p. 28) " When simulated acid rain (created in the laboratory) with a low pH has been sprayed in plants, detrimental effects may been seen but usually only at pH levels lower than those occurring now. These include damages to leaves and roots; slowdown of some biological processes such a nitrogen fixation; increased susceptibility to disease in the production of carbon cellular damage; and a decrease in the production of carbohydrates which can alter fruits, seeds, tubers, and roots the parts of the plants used for food." (Gay, 1983, 27) " Research has shown that acid rain can also affect the marketability of some crops. The quality, size, and appearance of the food products may be altered." (Gay, 1983, 27) If acid rain has fallen on a lake it will usually appear crystal clear because the acid have killed every single one thing in the lake. When a lake has
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reached a pH level of 5. 5 most clams, snails, and crayfish vanish then the empty shells almost immediately dissolve. At a pH of 4. 5 the lake would be considered dead, living things cannot live in the water. When you lime a lake it helps reduce the pH level of acid, but it does not restore the lake to its full potential. Acid rain can also be dangerous to humans. If acid rain falls on soil it releases metals such as aluminum, copper, mercury, lead, and many other metals. These metals are only harmful if they are separated from other elements in the soil. In 1952, over four thousand people died in London because of a dense blanket of acidic fog. Most that died were children or adults with breathing problems, because of the polluted air. If these poisons enter the body, they could burn the lung tissue, making breathing more difficult and may lead to suffocation. " In 1979 the lake trout of lake 223 still had abundant food and appearance normal. In 1982, with the lake's pH at 5.1, the adult trout were emaciated, and no young were being produced." (Pringle, 1988, 42) " Some researchers believe that sulfur compounds may be produced by biological processes in the sea, and these compounds can then be transformed in the atmosphere to sulfuric acids. But there is also a strong possibility that acidic pollutants from industrial centers are transported long distances to remote areas. One of the major difficulties in the acid rain studies has been tracking sulfur dioxide from its source to its final destination in the form of acid deposits." (Gay, 1983, 32) Not until the late 1980's did experts discover that the outer layer of
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