Acid Rain Essay Research Paper ACID DEPOSITION — страница 2

as coal and oil are largely to be blamed for half of the emissions of this gas (sulfur dioxide) in the world.” These environmental felons kill life everyday. Acid deposition is caused by the emissions of nitric oxide (NO), nitrogen oxide (NO2) and sulfur dioxide (SO2) into the atmosphere. These gases are emitted by natural sources such as volcanoes, sea spray, rotting vegetation, and plankton, but the amounts are not substantial enough to cause precipitation with pH levels that low. Acid precipitation is caused when emissions containing sulfur dioxide, nitric oxide, and nitrogen oxide, combine with moisture in the air to form acid precipitation. When combined with water, they complete a chemical formula, one that represents destruction and devastation. Dry Deposition is the

particles of the chemicals themselves suspended in the air. Effects on the Environment All forms of acid precipitation damage all kinds of vegetation. The problems caused by it are numerous and in most cases cause death, whether it be a tree, shrub, lake, stream, or fish. The effects, though, depend on weather conditions, humidity, sunlight , presence of other pollutants, length of time the pollutants have remained in the atmosphere, and buffering capacity . They also depend on contact with: ? Primary receptors – come into direct contact with pollutants (e.g. building, trees, plants, etc.). ? Secondary receptors – come into contact after they?ve come into contact with other materials (e.g. foliage of plants, soil beneath vegetation, etc.). ? Tertiary receptors – indirectly

affected (e.g. subsoil, bedrock, watercourses and lakes). All effects may come in combinations, separately, or all at once. Effects on crops Scientists have now received evidence that proves that acid deposition greatly effects agriculture, along with everything else. One some croplands, tomatoes grow to only half their full weight and the leaves of radishes wither. Nitrogen oxide is the culprit responsible for $2 billion to $4.5 billion worth of wheat, corn, soybeans, and peanuts. This decrease can hurt 3rd world countries, and augment the price of food worldwide. Thousands of people could starve due to this new scientific discovery. Effects on Forests A young man kills someone with his bare hands, and citizens cry out in rage. They say they will do anything to prevent him from

hurting another, killing another. Yet silently, everyday, vegetation is weakened, threatened and killed, far away or close to their homes, and they sit back and watch. Scientists have known for twenty years now the effects that acid deposition has on the forests. The forests themselves grow thinner, and slower, than their predecessors, due to the damage it has caused. Coniferous tree needles die-back , their growth is stunted, they loose their resistance to disease and drought, and they experience a lack of natural regrowth. Deciduous trees, on the other hand, grow discolored or misshapen leaves, experience early leaf fall, have dead tree tops and/or damaged bark, loose their resistance to drought and disease, and experience a lack of natural regrowth. The loss of feeder roots

and smaller tree rings are also effects. Basically, the forests are slowly dying off. Forests in high mountain regions receive additional acid from the acidic clouds and fog, which are often more acidic than the rainfall. When leaves are frequently bated in this acid fog their protective waxy coating can wear away. The loss of the coating damages the leaves and, and they become unable to produce enough food energy to remain healthy. Once trees are weak, they can be more easily attacked by diseases or insects that ultimately kill them. It seems that damage to plants through short periods of highly concentrated exposure is more are more damaging than prolonged exposure to weak concentrations of acids. Effects on Humans Humans don?t exactly react the same way to acid deposition as

the rest of nature. They don?t mutate, or fail to reproduce. They don?t yellow from the outside in, or slowly corrode until they vanish. “The links between acid pollution and human illness are generally unclear.” Acid deposition distributes toxic metals into our water systems, and are consumed when eat, or drinking. They have been linked to everything from headaches to cancer, brain damage and senile dementia. Aluminum, which acid deposition releases into the soil, is known to cause Alzheimer?s disease. Sulfuric aerosols have been known to cause bronchitis, tracheitis, respiratory problems, such as asthma, and poor visibility. Effects on Water Unlike the changes to the forest, lakes react in a slower fashion. “The effect of acid deposition on lakes is gradual, quiet and