Acid rain damage from

Acid deposition occurs when sulfur dioxide and nitrogen oxide emissions are transformed in the atmosphere and return to the earth in rain, fog or snow. Approximately 20 million tons of SOj are emitted annually in the United States, mostly from the burning of fossil fuels by electric utilities. Acid rain damages lakes, harms forests and buildings, contributes to reduced visibility, and is suspected of damaging health. 

Figure 7.2 Acid rain occurs when water comes into contact with sulfur and nitrogen oxides in the atmosphere, which can come from natural sources or from man-made sources like cars or power plants. These acid rain-damaged coniferous trees live in the Karkonosze National Park in Silesia, Poland.

We ve all heard about the ravages of acid rain. Resulting from toxic emissions in the environment, acid rain damages the leaves and needles on trees, reduces a tree s ability to withstand cold, drought, disease, and pests, and even inhibits or prevents plant reproduction. In an effort to stay alive and combat the acidity, tree roots pull important nutrients such as calcium and magnesium from the soil. These alkaline nutrients balance the effects of acid rain, but as they become depleted from the soil, the trees ability to survive is further strained. 

Reddy, M. M. (1988), Acid Rain Damage to Carbonate Stone A Quantitative Assess ment Based on the Aqueous Geochemistry of Rainfall Runoff from Stone, Earth Surface Processes Landforms 13, 335-354. 

Figure 6.1. Acid rain resulting from the introduction of sulfuric, nitric, and hydrochloric acids into the atmosphere by the burning of fossil fuels damages buildings, statues, crops, and electrical equipment in some areas of the world, including parts of the northeastern U.S.

Flue Ga.s Desulfuriza.tion. Citric acid can be used to buffer systems that can scmb sulfur dioxide from flue gas produced by large coal and gas-fired boilers generating steam for electrical power (134—143). The optimum pH for sulfur dioxide absorption is pH 4.5, which is where citrate has buffer capacity. Sulfur dioxide is the primary contributor to acid rain, which can cause environmental damage. 

The most evident damage from acid depositions is to freshwater lake and stream ecosystems. Acid depositions can lower the pH of the water, with potentially serious consequences for fish, other animal, and plant life. Lakes in areas with soils containing only small amounts of calcium or magnesium carbonates that could help neutralize acidified rain are especially at risk. Few fish species can survive the sudden shifts in pH (and the effects of soluble... 

Acid rain adversely affects trees as well (Figure A). It appears that the damage is largely due to the leaching of metal cations from the soil. In particular, H+ ions in acid rain can react with insoluble aluminum compounds in the soil, bringing Al3+ ions into solution. The following reaction is typical ... 

The world as we know it could not function without acids and bases. These chemical compounds are used extensively, from the chemical laboratory to the manufacturing industry. They are necessary for the proper functioning of the human body and for the health of the environment, too. Acids taste sour, break down metals, and react with bases. Without acids, soft drinks, lemonade, and tomato sauce would not taste the same way. Bases taste bitter, feel slippery, and react with acids. Without bases, cakes would be hard and flat, and laundry detergent would not clean. Both acids and bases can change certain vegetable substances a variety of different colors, and they can burn through human skin if not handled properly. Without acids and bases, we would not have dynamite, some heart medications, and fertilizers. On the other hand, without acids, we would not have damaging acid rain. And... 

Making a Model Acid precipitation often falls to Earth hundreds of kilometers away from where the pollutant gases enter the atmosphere because the gases diffuse through the air and are carried by the wind. In this lab, you will model the formation of acid rain to observe how the damage caused by acid varies with the distance from the source of pollution. You also will observe another factor that affects the amount of damage caused by acid rain. 

For these pollutants, the atmosphere has the ability to cleanse itself within hours especially when the effects of the pollutant are minimized by the natural constituents of the atmosphere. For example, the atmosphere might be considered to be cleaning as a result of rain. However, removal of some pollutants from the atmosphere (e.g., sulfates and nitrates) by rainfall results in acid rain that can cause serious environmental damage to ecosystems within the water and land systems. 

Description Sulfur dioxide (S02) is a gas resulting from the combustion of coal, mainly in power plants, and certain types of liquid fuels that contain sulfur. In addition, it is produced during the manufacture of paper and smelting of metals. It may cause respiratory problems and permanent damage to the lungs when inhaled at high levels. It plays a major role in the production of acid rain (EPA site). Carbon disulfide (CS2) has many industrial... 

Consequently, substantial concentrations of ozone can accumulate around electrical equipment and photocopying machines. Rooms containing these must be well ventilated, since ozone is toxic and can cause headaches and irritation of the mucous membranes, even in low concentrations. It has been suggested that ozone may be the cause of the excess death rate from leukemia (blood cancer) in electrical workers. Ozone is also extremely damaging to plant life, much more so than acid rain (Sections 8.4 and 8.5). It also attacks rubber and may cause rubber insulation on electrical equipment to perish rapidly. 

The toxicity of aluminum has been recognized most clearly by the development of bone disease caused by deposition of A1 in bones of patients on hemodialysis and in infants on intravenous therapy/ 6 Excessive A1 in the water used for dialysis may also cause brain damage. Dietary aluminum may be one cause of Alzheimer s disease/ h but this is controversial as is a possible role of aluminum in vaccines in causing inflammation in muscle.1) Solubilization of soil aluminum by acid rain has been blamed for the decline of forests in Europe and North America,) for the death of fish in acid waters,k and for very large reductions in yield for many crops/ An aluminum-resistant strain of buckwheat makes and secretes from its roots large amounts of oxalate which binds and detoxifies the Al3+ ions. ... 

Streams flowing over soil with low buffering capacity are equally as susceptible to damage from acid rain as lakes are. Approximately 580 of the streams m the Mid-Atlantic Coastal Plain are acidic primarily due to acidic deposition. The New Jersey Pine Barrens area endures the highest rate of acidic streams in the nation with over 90 percent of the streams acidic. Over 1,350 of the streams in the Mid-Atlantic Highlands (mid-Appalachia) are acidic, primarily due to acidic deposition. Many streams in that area have already experienced trout losses due to the rising acidity. 

Among the many dramatic effects of acid rain are the extinction of fish from acidic lakes throughout parts of the northeastern United States, Canada, and Scandinavia, the damage to forests throughout much of central and eastern Europe, and the deterioration everywhere of marble buildings and statuary. Marble is a form of calcium carbonate, CaC03, and, like all metal carbonates, reacts with acid to produce C02. The result is a slow eating away of the stone. 

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