acid rain
Acid rain is perhaps the most well known and recognizable form of pollution that is affecting the world today. Acidity is measured using a pH scale, with 7 being neutral. So anything below 7 is considered to be acidic, but as far as acid rain goes, the baseline for identifying acid rain is generally below the pH level of 5.6. But there have been many debates over this value and many scientists believe that it should be closer to a pH of 7. So any precipitation that has a pH value of less than 5.6 is considered to be acid precipitation. Readings of pH 2.4, as acidic as vinegar, were recorded during storms in New England and during one particular acid rain storm, the paint was actually stripped of a car and left it ruined (Tyson 1992). One of the main causes of acid rain is sulfur dioxide. There are natural sources that emit sulfur dioxide like volcanoes, sea spray, rotting vegetation, and plankton. But the burning of fossil fuels, such as oil and coal, are blamed for approximately half of the emissions of this gas in the world. When sulfur dioxide reaches the atmosphere, it oxidizes to form a sulfate ion and it then becomes sulfuric acid as it joins with hydrogen atoms in the air as it falls back down to earth. The
Sulfuric acid can affect lakes and aquatic ecosystems in indirect ways. It releases heavy metals present in soils to be dissociated and released. For example Al+2 is harmless as part of a compound, but because acid rain causes Al+2 to be released into the soils and gradually into the lakes and becoming lethal to the health of fish. So some fish can survive in water that has a pH level of below 5, but it all depends on the levels of other harmful substances like Al+2 and mercury in the water. In 1976, scientists did a study on a lake called lake 223. They monitored the pH levels of the water and noted that as the pH level went up over the years, a number of species of crustaceans died out. At a pH of 5.6, algae growth almost ceased and a great number of it all died out. Finally in 1983 the pH level went down to 5 and all that was left in the lake were thin, deformed adult fish that no longer had the capability of reproducing (Morgan 1999). This study shows how much damage acid rain does. One of the most serious impacts of acid rain is on forests and soils. Great damage is done when sulfuric acid falls onto the earth as rain. It washes away all the nutrients in the soil and aluminum that is present in the soil is freed and this toxic element can be absorbed by the roots of trees and thus be deprived of vital nutrients and die. (www.brixworth.demon.co.uk/acidrain2000/facts.htm). But not all sulfur dioxide is converted to sulfuric acid on the way back down to earth. In fact, a substantial amount can float into the atmosphere, move over to another area and return to the soil unconverted. As the gas returns to the land, it clogs up the stomata of leaves, and thus stopping photosynthesis. It is also thought that severe frosts may further aggravate the acid rain problem. With sulfur dioxide, ammonia, and ozone present in the air, the ability for trees to deal with frost is reduced dramatically. Ammonia oxidizes with sulfur dioxide to form ammonium sulfate and this product forms on the surface of trees. When the ammonium sulfate reaches the soils, it reacts to form both sulfuric and nitric acid. These conditions will stimulate
Some common words found in the essay are:
Title Morgan, , Decreased Ca+2, SO2 NO2, acid rain, SO3 SO3, sulfuric acid, sulfur dioxide, ph level, Canada Accompanied, ph levels, morgan 1999, effect acid rain, effect acid, fossil fuels, lakes aquatic, sulfuric acid directly, rain humans, acid rain sulfur, lakes aquatic ecosystems, effects acid rain,
Approximate Word count = 1452
Approximate Pages = 6 (250 words per page double spaced)
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