Acid Deposition Monitoring Network in East Asia

Acid deposition monitoring covers four environmental media - wet deposition, dry deposition, soil and vegetation, and inland aquatic environment.Monitoring for wet and dry deposition are implemented in order to measure concentrations and fluxes of acidic substances deposited to the ground, while monitoring for soil and vegetation, and inland aquatic environment are being implemented to assess adverse impacts on terrestrial and aquatic ecosystems.Monitoring

1. Wet Deposition:
Monitoring Interval - every 24 hours or every precipitation event for an urban, rural or remotesite
Major Parameters - Precipitation anaysis: pH, electrical conductivity (EC), concentrations of
sulfate (SO42-), nitrate (NO3-) and other ions

2. Dry Deposition:

Monitoring Interval - every day to two weeks, or every hour when measured by automatic instruments
Major Measurements - Gases: concentrations of sulfur dioxide (SO2), nitrogen dioxide (NO2), ozone(O3) and others Particulate components.

3. Soil and Vegetation:
Monitoring Interval - once three to five year
Major Parameters - Soil:pH, concentrations of exchangeable ions and effective cation exchange capacity (ECEC) Vegetation (forest): survey of tree decline, and general description of forest.

4. Inland Aquatic Environment:

Monitoring Interval - More than four times a year
Major Parameters - Inland water :pH, electrical conductivity (EC), alkalinity and ions

New Yorks Acid Deposition Monitoring Network

New York monitors and tests for acid deposition through the New York State Atmospheric Deposition Monitoring Network, which was designed in 1985 to carry out requirements of the State Acid Deposition Control Act (SADCA). Measurements of acid deposition and related quantities are used to assess the effectiveness of sulfur control policy and other strategies aimed at reducing the effects of acid rain.

The network's objectives are:

• Provide a consistent, quality-assured, long-term acid deposition database.
• Measure acid deposition in sensitive receptor areas.
• Measure acid deposition in urban and upwind areas.
• Use these data to perform spatial and temporal analyses of acid deposition, its precursors, and its effects.
• Track the effectiveness of programs to reduce acid deposition precursor emissions.

Site Classifications
The network is composed of three classes of monitoring sites which differ by the amount and kind of instrumentation used. They are designated "Type 3," "Type 2," and "Type 1."


Type 3: Sites have two types of instrumentation. The first is a tipping bucket rain/snow gauge to measure the amount of precipitation. The output signal is connected to either a recorder or a telemetry unit. The second device is a Viking Hyetometer which is a bucket type collector designed to collect samples under wet or dry conditions. Wet deposition samples are gathered in the lined buckets when precipitation is occurring. Because no adequate methodology has been established for analysis of dry side samples, only the wet side samples are analyzed.

Type 2 :Sites have all the devices operated at a Type 3 site and they also incorporate continuous monitoring instrumentation to measure the ambient concentration of selected components. These instruments are connected via telemetry to a central computer. Beginning in 1991, several low-level SO2 and ozone analyzers have been installed and are in operation. Type 2 Sites are also designed to measure relative humidity, temperature, and atmospheric pressure. Additional analyzers may be added, given adequate resources.

Type 1 :Sites, in addition to having the instrumentation used at Type 2 Sites, also measure wind speed and direction, and calculate horizontal sigma (wind direction variability).

REAL-TIME MEASUREMENT OF ACID RAIN

A microprocessor-based acid rain monitor was used to make real-time measurements of conductivity and pH of rainwater within individual storms. The automated measurements were compared with laboratory analyses of a subset of the samples taken. The laboratory measurements tended to overestimate the pH because of temperature induced changes in dissociation and Henry's Law constants affecting ionic compounds in the rainwater.

 The measurement fact due to these effects may result in average hydrogen ion concentrations being underestimated by approximately 10 to 15% at UK sites. The greatest systematic discrepancies would be anticipated at highly polluted sites and during low temperature acidic episodes. The concept of a rainwater acid fraction was investigated and found to be useful for quality control and interpretative purposes. 

The field measurement of conductivity of low ionic strength samples was slightly lower than the corresponding laboratory measurement, possibly caused by limited resolution of the conductivity probe or dissolution of fine particulate material.

ECOSYSTEM RECOVERY FROM ACID DEPOSITION

Ecosystem recovery is a phased process that involves the reversal of degraded chemical and biological conditions.Recovery from acid deposition involves decreases in emissions resulting  from regulatory controls, which in turn lead to reductions in acid deposition and allow chemical recovery. Chemical recovery is characterized by decreased concentrations of sulfate, nitrate, and aluminum in soils and surface waters. If sufficient, these reductions will eventually lead to increased pH and ANC, as well as higher concentrations of base cations. As chemical conditions improve, the potential for the second phase of ecosystem recovery, biological recovery, is greatly enhanced.

An analysis of the scientific literature suggests that the following five thresholds can serve as indicators of chemical recovery. If chemical conditions in an ecosystem are above these thresholds, (or in the case of aluminum, are below the threshold) it is unlikely that the ecosystem has been substantially impaired by acid deposition. Conversely, if chemical conditions are below these thresholds, (or in the case of aluminum, above the threshold) it is likely that the ecosystem has been, or will be, impaired by acid deposition.

As chemical conditions in soils and surface waters improve, biological recovery is enhanced. Biological recovery is likely to occur in stages, since not all organisms can recover at the same rate and may vary in their sensitivity to acid deposition.The current understanding of species’ responses to improvements in chemical conditions is incomplete, but research suggests that stream macro-invertebrates may recover relatively rapidly, while lake zooplankton may need a decade or more to fully re-establish. Fish populations in streams and lakes should recover in 5-10 years following the recovery of the cro-invertebrates and zooplankton which serve as food sources. It is possible that, with improved chemical conditions and the return of other members of the aquatic food web, the stocking of streams and lakes could help to accelerate the recovery of fish

Acid Rain Research

The researchers discovered that acid rain inhibits a swampland bacteria from producing methane, a greenhouse gas. Methane, a gas that contributes to warming our planet, is produced by natural processes and human activities. Increased amounts of methane and other greenhouse gases in our atmosphere are warming the Earth beyond its average temperature.

Carbon, heat and moisture are known to influence methane production by members of the Archaea, single-celled creatures. Under normal conditions, these microbes consume organic carbon in the soil for energy and release methane as a byproduct. Wetlands provide an ideal environment for these microbes. When acid rain drops sulfate onto wetlands, another type of bacteria, ones that reduce sulfate are able to out compete the Archea, limiting the total production of methane.

Wetlands may produce as much as 320 million tons of methane annually but only about half of that, or 160 million tons, is ultimately released to the atmosphere. The other 160 million tons never makes it to the atmosphere because it is destroyed via oxidation as it moves from wet soils below the water table through dry soil to the surface. Despite substantial oxidation, natural wetlands remain the single largest source of methane emission accounting for about one third of the global annual total methane.

"It's a complicated process because multiple factors at microscopic to global scales interact in these processes," said Elaine Matthews, a scientist at NASA's Goddard Institute for Space Studies (GISS), New York. Matthews is co-author of the study on acid rain and methane in wetlands. "The maximum emission of methane from wetlands occurs when conditions are warm and wet, while the biggest reduction in methane emissions is achieved when the location of wetlands, sulfates contained in acid rain, high temperatures and substantial precipitation all come together, to reduce optimal methane emissions from wetlands." These factors vary over time and space.

Sites at High Risk from the Hazards Associated with Acid Rain

Acid rain only causes indirect damage to living human beings, primarily through its reactions with Volatile Organic Compounds (VOCs) to form ground-level Ozone (smog), it causes tremendous damage to soil fertility, aquatic life, and durable inorganic materials such as stone and metals. Some of the greatest measurable effects of acid rain can be observed on human constructions, particularly old buildings with facades built of corrosion-prone metals such as copper and porous stone such as limestone. 

Endangered Heritage Sites due to acid rain:

1. LESHAN GIANT BUDDHA, MOUNT EMEI (China, Buddhist)
The Leshan Buddha has fallen victim to pollution emanating from unbridled development in the region. In this case, the culprit has been determined to be the growing number of coal fired power plants located near the Giant Buddha, specifically, the toxic gases that their smokestacks spew into the air; these eventually return to the earth as acid rain. Over time, the Buddha's nose has turned black and the curls of his hair have begun to fall from his head. The local government has shut down several factories and power plants in close proximity to the Leshan Giant Buddha, which has stopped the blackening of his face from soot; however, acid rain continues to compromise the structural integrity of this masterpiece. The Leshan Giant Buddha, which was designed carefully to survive millennia of floods and earthquakes, is now at high risk of rapid deterioration from the unbridled pace of industrial development in western China.

2. ACROPOLIS OF ATHENS (Greece, Ancient Greek)
In recent decades, as Greece has experienced substantial economic expansion and development, pollutants and heavy vehicle emissions from the booming modern city of Athens have contributed to acid rain in the region. The monumental and sculptural stone of choice for the ancient Greeks, marble, is highly susceptible to heavy surface degradation from even low levels of acid rain. The Parthenon’s magnificent marble relief frieze panels, for instance, have been chemically transformed by acid rain into soft gypsum. As details are lost and the chemical transformation soaks deeper into the marble on these vital monuments, pieces of them have begun to crack and fall off, with structural collapse a possibility in the not-so-distant future. Further complicating the situation is the seismically-active nature of the region, as earthquakes would have a far greater effect on marble constructions that have slowly transformed into gypsum than with unaltered marble.

3. TAJ MAHAL (India, Mughal Islam)
The Taj Mahal is India’s preeminent tourist destination, attracting between two and four million visitors annually. In an effort to control the deleterious effects of pollution, tourist traffic is not allowed near the site, with most visitors riding in by electric bus from nearby carparks. This has not, however, slowed down the degradation of the Taj Mahal’s marble facades from acid rain generated from local foundries and an oil refinery. The once brilliant-white Taj has been losing its luster, dulling into a sickly pale shade.

4. DAMPIER ROCK ART COMPLEX (Australia, Australian Aboriginal)
The Burrup Peninsula’s rock art sites have been listed as endangered by the National Trust of Australia, but industrial expansion since 1963 across more than 25% of the rock art area has posed severe threats to the site. Much of the heaviest (mining and petrochemical) industry is located immediately adjacent to some of the most sensitive collections of artwork. Acid rain from this has begun to erase many of the carefully, but often shallowly, engraved rock surfaces, and studies by archaeologists and geologists have postulated that most of the rock art will disappear completely by the middle of the 21st century.

5. LONGMEN GROTTOES (China, Buddhist)
The Longmen Grottoes are arguably the most famous ancient sculptural site in China. Located in Henan Province and positioned on two opposing bluffs above the Yi River, most of the artwork is Buddhist in nature and dates to the late Northern Wei and Tang Dynasties (316-907 AD). 2345 niches were carved from the rock, densely worked over the space of approximately a kilometer to the north and south, and they house more than 100,000 statues (also carved from the rock). Accompanying inscriptions bear more than 300,000 Chinese characters and are a treasure trove of historical and linguistic data. The Longmen Grottoes are a masterpiece of Buddhist art and are considered one of the world`s most important sculptural sites.

Effect Of Acid Rain On Humans

Most importantly, acid rain can affect health of a human being. It can harm us through theatmosphere or through the soil from which our food is grown and eaten from. Acid rain causes toxic metals to break loose from their natural chemical compounds. Toxic metals themselves are dangerous, but if they are combined with other elements, they are harmless.They release toxic metals that might be absorbed by the drinking water, crops, or animals that human consume. These foods that are consumed could cause nerve damage to children or severe brain damage or death. Scientists believe that one metal, aluminum, is suspected tolerate to Alzheimer’s disease. One of the serious side effects of acid rain on human is respiratory problems.

 The sulphur dioxide and nitrogen oxide emission gives risk to respiratory problems such as dry coughs, asthma, headaches, eye, nose, and throat irritation.Polluted rainfall is especially harmful to those who suffer from asthma or those who have hard time breathing. But even healthy people can have their lungs damaged by acid air pollutants. Acid rain can aggravate a person’s ability to breathe and may increase disease which could lead to death. In 1991, the United States and Canada signed an air quality agreement. Ever since that time, both countries have taken actions to reduce sulphur dioxide emission. The United States agree to reduce their annual sulphur dioxide emission by about ten million tons by the year 2000. A year before the agreement, the Clean Air Pact Amendment tried to reduce nitrogen oxide by two million tons. This program focused on the source that emits nitrogen oxide, automobiles and coal-fired electric utility boilers. Reducing nitrogen oxide emission in a utility plant starts during the combustion phase. A procedure called over fire air is used to redirect a fraction of the total air in the combustion chamber.

To reduce sulphur dioxide emission utility plants are required to do several steps by the Clean Air Act Amendment.Before combustion, these utilities plants have to go through a process call coal cleaning. This process is performed gravitationally. Meaning, it is successful in removing pyritic sulphur due to its high specific gravity, but it is unsuccessful in removing chemically bound organic sulphur. This cleaning process is only limited by the percent of pyritic sulphur in the coal. Coal with high amount of pyritic sulphur is coal in higher demands. Another way to reduce sulphur dioxide before combustion is by burning coal with low sulphur content. Low sulphur content coals are called bituminous coal. This process in reducing sulphur dioxide is very expensive due to the high demand of bituminous coal.Acid rain is an issue that can not be over looked. This phenomenon destroys anything it touches or interacts with it. When acid rain damages the forest or the environment it affects humans in the long run. Once forests are totally destroyed and lakes are totally polluted animals begin to decrease because of lack of food and shelter. If all the animals, which are our food source, die out, humans too would die out.

Acid Rain Program

The Acidifying Emissions Task Group submitted its report Towards a National Acid Rain Strategy to the National Air Issues Coordinating Committee. The report responds to the request of the Energy and Environment Ministers for federal and provincial governments to develop a long-term acid rain strategy to mitigate the environmental and human health effects of acidifying emissions.

The Ontario Ministry of the Environment released a comprehensive review package of environmental regulations that included the consolidation of the four acid rain regulations into a single regulation.

Following the release of an "Integrated Independent Performance Assessment" of its nuclear operations, Ontario Hydro announced, on 13 August 1997, that it would lay up indefinitely seven of its 19 operating nuclear power stations (the four Pickering A units and the remaining three Bruce A units). To replace the electricity generated by these Pickering and Bruce units, Ontario Hydro announced that it would operate existing fossil plants such as Nanticoke and Lambton at higher levels and bring the mothballed units at the Lennox station back on stream.

The increased burning of fossil fuels is expected to add about 80 kilotonnes/year to Ontario Hydro’s SO2 emissions. As these emissions are currently about 85 kilotonnes/year, it is anticipated that Ontario Hydro will continue to operate within its regulated limit of 175 kilotonnes SO2. Total emissions for Ontario will also increase but will remain within the limit set by the Eastern Canada Acid Rain Program.

EFFECTS OF ACID RAIN, SNOW AND FOG

Acid deposition, from human-caused emissions of oxides of sulphur and nitrogen, is probably the greatest threat to small boreal lakes in Canada and Eurasia.[2] Acidifying sulphur oxide emissions have been reduced by over 50% in Canada. Legislation has been passed to compel similar reductions in the United States by early in the twenty-first century. However, these measures are estimated to have reduced the potential effect of acid precipitation on Canadian lakes by only about half.

The rapid decline in DOC caused by acidification caused much greater increases in UV-B penetration than climate warming alone. In the most acidified lake, 302S, the depth of 1% UV-B penetration increased from about 0.3 meters to over 2.8 meters --nearly a tenfold increase. As a result, the proportion of the lake's volume exposed to greater than 1% of UV-B increased over eightfold, from 6% to nearly 50%.Overall, the study's authors estimate about 140,000 of the nearly 700,000 lakes (i.e., about 20 percent) in eastern Canada may have DOC concentrations low enough for UV-B penetration to be of concern. The highest concern, they say, must be for clear, shallow lakes, streams and ponds, where even modest declines in DOC may eliminate the small regions that are deep enough to provide refuges from damaging UV- B radiation. 

However, most species disappear in natural aquatic ecosystems at higher pH values (less acidic conditions) than predicted by laboratory tests, thus suggesting that, in ecosystems, additional stresses enhance the effects of acidification. It is possible that one such stress is the increased exposure to UV-B caused by DOC decreases in acidified lakes. These results indicate that in aquatic systems, climate warming and/or acidification can increase the exposure of organisms to UV-B much more than changes in UV-B caused by depletion of the stratospheric ozone layer. The authors say that, in clear oligotrophic lakes [(.e., clear, healthy lakes that lack excessive nutrients for plants, and have plenty of dissolved oxygen), the decreases in DOC caused by climate warming, drought and acidification should be of much more concern than depletion of stratospheric ozone, so far as UV-B exposure is concerned.

The Negative Effects Of Ozone Depletion Due To Acid Rain

Acid rain has been around for a long time. It was first noticed around the 17  century during the industrialization period. Scientists have been paying attention to "acid rain" since that time and the effects it has had on the plants, animals, humans etc. Acid rain is very dangerous as most people know. First off the term is not totally correct and scientists prefer the terminology acid depositions. The reason these scientists believe that it is called acid depositions instead of acid rain is simply because the acid which was formed by pollution can in fact return to the earth as either solid or a gas and not only in the form of rain. 

Acid depositions can come in rain, fog or even snow. Industries, factories, vehicles, aerosol cans, etc are all causes for "acid rain". This is because all of these things increase the level of sulphur dioxide and nitrogen in the air we breathe in. These chemicals will later transform into sulphuric acid as well as nitric acid which in the long run will come down in the form of "acid rain". Electric companies have to burn a lot of coal, which contains a very low amount of sulphur, in a day's time which will increase the level of sulphur dioxide in the atmosphere. But the electric companies are not the only one's to blame; a lot of other companies and industries have to process raw ore (a mineral or a numerous amount of minerals which a valuable or constituent can be profitably mined or extracted) so they can obtain copper, zinc, and nickel. 

The problem with that is that copper, zinc, and nickel are also causes of acid rain. Most pollution, if not all, is caused by humans in the formed of vehicles, industries etc. The accidents in which man has no control over such as volcanic eruptions, lightning, decay etc are a cause for the different pollutants in the atmosphere but nothing can be done to avoid this. But this is not a great risk to the atmosphere and us when one considers that 90% of the sulphur dioxide in our atmosphere and 95% of nitrogen oxides is caused by man. Which leaves about 10% and 5% respectively are caused by nature which is very minimal. The biggest problem about "acid rain" is that it does not stay where it was created. Since acid rain takes many forms, it will travel everywhere and create itself somewhere else thru the aid of wind, water, etc. 

The United States is well known to be a big part of the pollutants in the world; for example is it believed that 50% of the "acid rain" in Canada is caused by the pollution in America. It is important to know that pollution is not the only cause of "acid rain". If you take rainfall as an example, even if there is no pollution at all in the atmosphere, the rain itself is still acidic. The rain in rainfalls has a pH of roughly 6.0. The cause of this is because there is carbon dioxide in our atmosphere and when it mixes with water it created carbonic acid. Since this is not a perfect world, there will always be pollution in the world and because of these pollutants it affects the pH level and makes it drop. When the pH level reaches below 5.5 it is classified as "acid rain". The lowest ever recorded pH level was around 2 - 2.5.

Effective Ways To Reduce The Threat Of Acid Rain

The number of possible solutions that are available to us are aplenty. What matters more is to consciously enforce these solutions to stop this rain and to do so on a wide scale. People all over the world must be made aware of the causes and effects of this rain, and they should be thoroughly educated about it. Solutions to can only be successful through cooperation. Given below are a few solutions, which can greatly reduce the threat of acid rain, if strictly followed by a large number of people.

One of the most fundamental solutions is to utilize fuels that burn more cleanly, or to burn coal more efficiently. This will greatly reduce the possibilities of this rain developing in the atmosphere.As fas as industrial power plants are concerned, the best solution is to attach devices known as 'scrubbers' in the chimneys of these plants. These scrubbers reduce the amount of sulfur produced in the smoke by 90 - 95%vehicles and cars must be mandatory required to comply with very tight and efficient emission standards. Fitting catalytic converters into the exhaust pipes of vehicles, also reduces the amount of sulphur dioxide produced by the vehicles.

We can make a lot of changes on a personal level as well, in order to combat acid rain. We should restrict the use of our cars and vehicles and utilize other modes of transportation on a more frequent basis. We should also remember to turn off all our lights and electrical devices in case we are not using them.For industrial power plants, there are many more solutions that must be enforced, as they are clearly the biggest contributors to the formation of acidified water droplets in the atmosphere. Industries must regularly inspect and clean all their emission equipment and chimneys and pipes.

All these solutions will be pointless unless people are informed and educated about the ill-effects and harms of this rain. A widespread and nationwide effort must be made to make people aware. Only after that is done, will all the solutions actually make a difference.

Management Of Calcium In Plants Effect Acid Rain

A new understanding of how plants manage their internal calcium levels could lead to modifying plants to avoid damage from acid rain. The pollutant disrupts calcium balance in plants by leaching significant amounts of the mineral from leaves as well as the agricultural and forest soils the plants live in.

"Our findings should help scientists understand how plant ecosystems respond to soil calcium depletion and to design appropriate strategies to protect the environment," said Zhen-Ming Pei, a Duke University biologist who led the study, which is published in the journal Science."
The research was supported by the National Science Foundation (NSF), the U.S. Department of Agriculture and Xiamen University in China.

To grow, a plant needs a reliable supply of calcium, which enters the plant dissolved in water the roots take in from surrounding soil. As the water circulates through a plant, dissolved calcium gets shuttled where it is needed to give the plant's cells their structural rigidity. But calcium supplies coming into the plant cycle up and down over the course of the day, dropping to a minimum at night.

Calcium is a key regulator of vital physiological functions in both plants and animals.The discovery of the relationship between calcium in soil, in plant cells, and cellular mechanisms sheds new light on the role of this important mineral in plant growth and development.Plants use molecular sensors and flows of chemical messengers to detect and regulate the storage and distribution of vital nutrients such as water and calcium. To track the calcium sensors in the laboratory plant Arabidopsis, Pei and his coworkers used molecules originally found in jellyfish that emit light in the presence of calcium. To deduce the calcium sensor's role, the researchers also introduced an altered version of the sensor protein that abolishes the sensor's effects.

According to Pei, the sensors try to detect how much calcium there is and coordinate that level with growth and development. "If the sensors detect there is not enough calcium, they may tell the plant to hold off on growing, at least until it gets more calcium."

Although acid rain robs soil of much of its calcium, enough is still left for plants to live on, Pei added. But he suspects that sensors may misinterpret "less" as "too little" in those plants and unnecessarily signal for growth shutdowns."Some soils have lost as much as 75 percent of their calcium during the past century," Pei said. "One way to respond is to add new calcium to the soil. But we can't do that everywhere that it's needed, and it is also expensive. Perhaps a plant's calcium sensors could instead be tricked into interpreting "less" as "still enough" and keep building new cell walls."

Steps To Prevent Acid Rain

Acid rain is caused by air pollutants such as sulphur dioxide or nitrogen oxide. These chemicals are produced by the burning of fossil fuels, the smelting of ore, the burning of coal, and the processing of natural gas. Then the chemicals can travel long distances by wind, mix with precipitation, and fall on the earth, causing damage to plants, animals, and our health. Electric companies and other industries that burn coal produce sulphur dioxide, and the main cause of nitrogen oxide is vehicles and fossil fuels.

One side of prevention is government environmental regulations, to limit the quantity of emissions released into the atmosphere. To follow these regulations, industries can add “scrubbers” to their smoke stacks to reduce the amount of sulphur released. Another option is washing the coal before it is burned, which reduces the amount of sulphur in the coal. To reduce the amount of car exhaust pollution, catalytic converters can be used in vehicles to make the exhaust less harmless.

On a more personal level, there are many things you can do to help prevent acid rain. Try to use your car as little as possible: walk, use public transportation, and carpool. Turn the heat down in your house, and don’t use air conditioning (these things require more gas burning). Conserve water by running a washing machine or dishwasher only with a full load. And remember to turn off lights, and use energy efficient lightbulbs! By following these tips, you will reduce the emissions of fossil fuels by using less energy. If we all pitch in and do our part, we can improve our quality of life and the beautiful earth on which we live.
 

Acid Rain in South Korea

Environmental statistics reveals that the pollution of acid rain in South Korea is a serious issue. Yet the awareness of people is low. Even after a gradual decrease of pollutant emission in Korea, the acidity has not been reduced. There no boundaries in the atmosphere are set and the influence of the neighboring countries such as China is apparent. Governmental efforts among China, Japan and Korea have been made on this issue. However, not much progress has been observed. Along with the governmental activities, therefore, an active monitoring of the pollution among the countries and the promotion of environmental awareness at the civil level including especially the middle and high schools are highly recommended. It will be this young generation who will face damaged country as inheritance not the current generation.


Occurence And Distribution of Acid Rain In South Korea:

Acid rain has become a worldwide issue as environmental problem since 1980's. From the latter part of 1980's, nations regulated the emission of sulpur oxides and nitrogen oxides.Actually the release of sulfur oxides and nitrogen oxides has been reduced substantially since 1990's and it appeared that the problem of acid rain was almost solved. The discharge of sulpur oxides was reduced. Nevertheless, the acidity of rain was not weakened. The reason was the reduction of alkaline materials simultaneously that neutralized the acidity of rain [3]. Alkaline dust and suspended solids were reduced as road pavement expanded. Alkaline dust became less in the air also through the efforts of reducing dust discharges that were produced from the factories and power plants. 

As a result, acid rain appears still strong in 2011 in South Korea. Rather, public attention decreased than before. It seems that acid rain is not a top priority any more due to other environmental issues. In order to achieve more substantial results, a couple of  obligatory actions should be followed. First, in monitoring each country, we propose a swapping of specialists. For example,Korean specialists monitor Japan's environment and Japanese specialists check Chinese environment and so forth. The specialists who take part in monitoring prepare a report and  present the results in the joint environment Minister meeting. Based on these monitoring, each country is expected to set the goals of reducing the pollutants at the periods of 5, 10 and 15 years. Also we suggest that a protocol with these reduction goals written on it be signed at the summit meeting

Lastly the adult generation is bound in political and economical system. They may not see the environmental issue as top priority. After all it will be the young generation, not the current generation, who will live in an environmentally devastated world if we do not act now accordingly now. That is why the young generation should speak out and take actions now.

Effect Acid Rain On Canadians

What is the link between acid rain and human health?
Sulphurdioxide can react with water vapour and other chemicals in the air to form very fine particles of sulphate. These airborne particles form a key component of urban smog and are now recognized as a significant health hazard.

What are the health effects of particulate matter (PM)?
Fine particles, or particulate matter (PM), can lodge deep within the lungs, where they cause inflammation and damage to tissues. These particles are particularly dangerous to the elderly and to people with heart and respiratory diseases. Recent studies have identified strong links between high levels of airborne sulphate particles and increased hospital admissions for heart and respiratory problems, increased asthma-symptom days, as well as higher death rates from these ailments.

Pyramid
The air pollution health effects pyramid is a diagrammatic presentation of the relationship between the severity and frequency of health effects, with the mildest and most common effects at the bottom of the pyramid, e.g. symptoms, and the least common but more severe at the top of the pyramid, e.g. premature mortality. The pyramid demonstrates that as severity decreases, the number of people affected increases.

What are the costs to Canadians of these health effects?
By using computer models, scientists and economists can estimate the costs of these health effects to Canadians. They do this by computer simulations, where they eliminate SO2 emissions in increasing amounts to predict how the cases of heart and respiratory problems and premature mortality would decline. This decline in health effects represents a significant potential benefit to Canadians; however, it also represents the cost to Canadians of living with current SO2 emission levels.

For example, the expected health benefits to Canada of a 50% SO2 reduction in both eastern Canada and the U.S. (i.e., reductions above and beyond the current commitments in the Eastern Canada Acid Rain Program and U.S. Acid Rain Program) are:

550 premature deaths per year would be avoided;

• 1,520 emergency room visits per year would be unnecessary; and
• 210,070 asthma symptom days per year would be avoided.
• Economists estimate that society values these health benefits in a range from just under $500 million per year up to $5 billion per year.

The U.S. has also estimated the health benefits of their current Acid Rain Program, both to their citizens as well as to Canadians. The average total annual estimated health benefit  for  United States is US$10.6 billion, and rises to US$40.0 billion later, when the U.S. Acid Rain Program is fully implemented.

The estimated benefits for Canada occur primarily in the Windsor-Quebec corridor, where the greatest share of the Canadian population likely to be affected by transboundary transport of SO2 emissions from the eastern U.S. is located. The average total annual estimated health benefit for Canada is US$955 million, or well over a billion Canadian dollars.

Geographic Scenario of Acid Rain In India

By the year 2020, in India alone, the energy demand is expected to increase by 300% from the present level. If urgent prevention and control measures are not put in place from now, the SO2 emissions, as per TERI estimates, are expected to shoot-up more than the energy demand! In fact the model simulation shows a possibility of increase in SO2 emissions over present levels. Hence, even though the sulphur deposition levels in much of India today are below the critical levels for acid rain, by the year 2020 the picture will be painfully different, if immediate mitigative steps are not taken now.

Like China, in India too the main threat of an acid rain disaster springs from our heavy dependence on coal as a major energy source. Even though Indian coal is relatively low in sulphur content compared to the nature of coal reserves of other countries like China, what threatens to cause acid rain in India is the concentrated quantity of consumption, that is expected to reach very high levels in some parts of the country by 2020. As energy requirements in India are growing rapidly in tune with the growing economy, coal dependence in the country is expected to grow threefold over the current level of consumption, making the clouds of acid rain heavier over many highly sensitive areas in the country like the northeast region, parts of Bihar, Orissa, West Bengal and coastal areas in the south. Already the soils of these areas have a low pH value, which acid rain will aggravate further making them infertile and unsuitable for agriculture. The GREEN India 2047 project of TERI has estimated that India is already losing between 11% to 26% of agricultural output on account of soil degradation. Acid rain would only increase this figure significantly.

 The prospect of increasing consumption of coal in Asia makes the acid rain threat even more real than ever. Possible options for mitigation are: radical improvements in energy efficiency, a switchover to low sulphur fuels like natural gas, greater use of renewables, major cut-down and removal of sulphur from crude oil distillates like diesel, fuel oil, etc., and finally, the widespread use of state-of-the-art pollution control devices in all polluting sectors of the economy. As experience stands in Europe and north America, the threat of acid rain was severely dealt with in these regions through heavy spending on SO2 abatement technologies and rapidly cutting down the dependence on coal by shifting to natural gas and nuclear energy. But, action in these regions came only after a considerable amount of ecological damage. In the 1960s, fish populations in the Scandinavian countries were showing a rapid decline as a result of acid rain. The infamous forest dieback in some parts of central Europe was also from acid rain. Thus, experience from elsewhere bears out clearly enough that the whole problem as it confronts India needs proactive handling.

The issue of rapidly growing SO2 emissions, the resultant sulphur deposition and the threat of acid rain in many areas of Asia is a transboundary problem involving many countries and therefore, its solution calls for regional initiatives. In Europe, the worsening situation of acid deposition from many countries in ‘70s and the related concerns about the pollution being carried over long distances, led to the signing of an international agreement in 1979, called "The Convention on Long-Range Transboundary Air Pollution". The signing of subsequent protocols led to binding commitments from European countries to limit and reduce their transboundary emissions of air pollutants. The worsening crisis of a long term acid-rain catastrophe in Asia, in the very near future, surely calls for urgent moves towards a similar agreement and binding protocols between the nations exposed to this threat in the not too distant future. And the action must begin now, as experience shows that all international agreements with binding commitments take long to bear fruit

Acid Rain In Europe

Over the last twenty years, policy-makers in Europe have been attempting to solve the problem of acid rain using detailed analysis grounded in natural science and economics. The results are impressive, as Europeans have successfully implemented a number of international agreements to reduce pollution emissions, agreements that in theory achieve the greatest environmental benefit at the lowest aggregate cost across Europe. This study examines the analysis on which these policies were based. First, it finds a pattern of investigating the use of cost-benefit analysis, together with a lack of usefulness associated with the actual results of such analysis. Second, it finds that the analytic framework that came to replace cost-benefit analysis— "critical loads"— contained many of the same uncertainties and political decisions that had plagued cost-benefit analysis. Nevertheless, "critical loads" analysis was temporarily seen as less value-laden and more reliable, and contributed significantly to policy development. The desire for rapid action led policy-makers to ignore or to overlook the politics and uncertainties inherent in efforts at scientific assessment and modeling.

It was Professor Sten Nilsson of IIASA’s Forest Study who first drew attention to the impact of pollution on Europe's forest resources, advocating the formulation of a convention on forest decline in Europe.His recommendation came in response to growing concern about damage to European forests attributed to air pollution and as a result of intensive collaboration between IIASA’s Transboundary Air Pollution Project and the Forest Study in efforts to quantify the problem.Combining its unique database on forest resources in Europe with projections on forest soil acidification obtained using IIASA's RAINS (Regional Acidification Information and Simulation model), IIASA’s Forest Study was able to quantify the impact of air pollution on Europe’s forest resources.

The work revealed that 35% of Europe’s coniferous forest and 9% of its deciduous forest areas were affected by nitrogen deposition levels (caused by nitrogen oxide emissions) in excess of those established by the Economic Commission for Europe  (ECE). In addition, 79%   of Europe’s coniferous forest areas and 39% of its deciduous forest areas were currently affected by levels of sulfur deposition in excess of the targets set by the Beijer Institute of Ecological Economics.

Excess deposition of acids and exposure to atmospheric pollutants will damage trees of different types and ages, resulting in leaf and needle loss. Because the health of a tree
affects its growth rate, and both this and life expectancy affect the value and timing of
harvests, these calculations were important for forest industries, as well as from an ecological perspective.

Despite the current agreements on reducing emissions levels, the area of forest likely
to be affected by excess sulfur deposition in the future was unlikely to change, according to IIASA scientists, unless planned expenditures on emission control were increased or reallocated. Moreover, the work revealed that many of the areas likely to suffer from excess sulphur deposition would also experience excess nitrogen deposition and troubling levels of atmospheric ozone. This implied that many trees would suffer the effects of multiple pollutants.

Monitoring Of Acid Rain

Continuous emissions monitors (CEMs) tell us how much of a pollutant a power plant (or other affected facility) emits. Under the Acid Rain Program, each affected unit must monitor emissions of sulfur dioxide and nitrogen oxides. Most also measure carbon dioxide. CEMs are the most common way to monitor emissions, but in some cases, Utilities may use an approved alternate method. For example, if a unit burns oil and they know the sulphur content of the oil and the amount they used, they can compute the amount of sulphurdioxide they will emit.

Each plant in the acid rain program must submit a monitoring plan to EPA and revise it as their monitoring system changes. This document tells which monitors will be used, where they will be located, and how the data will be gathered and sent to EPA. If a plant’s monitoring system changes, they must revise their monitoring plan.

There are several ways to monitor emissions from a plant. We measure nitrogen oxides by taking a sample of the gas emitted thought the plant’s smokestack and analyzing it. In some cases sulphurdioxide is measured this way, but we can also compute sulphur emissions from the fuel’s sulphur content, as noted above. When plants use natural gas, which contains only traces of sulfur, we may estimate the plant’s emissions by assuming the gas contains a certain low amount of sulfur. Sulfur emissions from such plants are so low that an actual measurement of sulfur dioxide is impractical.

Power plants must submit data whenever they are operating. If their monitor is not operating, they must report a "default" value, which is generally the maximum amount of the pollutant they can emit. EPA gathers the data, and tabulates the emissions form each plant.

Major Problematic Areas in Canada Due to Acid Rain

Eastern Canada

The problem areas of Canada are primarily in the eastern provinces that lie on the Canadian Shield and, therefore, lack natural buffers. Ontario, Quebec, New Brunswick and Nova Scotia are the most significantly damaged by acid rain. Most of the emissions that impact eastern Canada are produced at the large metal smelters in central Ontario and Quebec. Emissions from the US also affect Canada’s eastern region. In the US, the greatest amount of emissions comes from a high density of coal fired power plants in the eastern states. Weather systems carry these pollutants from the upper mid western US states across southern Ontario, southern Quebec and into the northeastern US. Pollutants also travel up the northeast corridor of the US into the Atlantic Provinces. 

Western Canada

Major emissions sources that impact western Canada are located in Alberta (from upstream oil and gas production and oil sands), southern Saskatchewan (from electric power generation) and northern Manitoba (from mining and smelting). However, there is currently not enough information to tell us how acid rain is affecting these ecosystems. Historically, western Canada has experienced less industrialization than eastern Canada. This factor, combined with east wardly moving weather patterns and acid resistant soils, has so far protected much of western Canada from the damage of acid rain. Not all areas in western Canada are naturally protected. Some lakes and soils rest on granitic bedrock, such as is found in areas of the Canadian Shield, in northeastern Alberta, northern Saskatchewan and Manitoba, parts of western British Columbia, and the Northwest Territories . Ecosystems in these areas are as vulnerable to acid rain as those found in northern Ontario. Acid rain may also become a regional problem downwind of the Alberta oil sands projects, where rapid expansion of bitumen extraction industries is expected to cause large increases in emissions of SO2  and NOX  in the next 20 years. A big concern to scientists is that if SO2  and NOX emissions continue to increase in western Canada, the same sort of acid rain damage that has happened in eastern Canada could occur in the west. 

Acid Rain In Canada

Not all areas of Canada are affected equally by acid rain.This is because areas differ in their ability to offset or neutralize acidity. This is largely determined by the type and rate of weathering of the soils and bedrock in the region.A region’s underlying bedrock (the geologic deposit from which a soil is derived by weathering) is the most important factor on how sensitive an area will be to acid rain. Alkaline substances, such as calcium, magnesium and potassium (known as “base cations”), are found in the earth’s bedrock and soil.

 In essence, when an acid and a base combine, they cancel each other out, producing a neutral substance. When the rain is only mildly acidic, there are enough alkaline substances to balance the acidity and neutralize the effects on the soil and water. However, when the rain is highly acidic, these acid-buffering substances can become depleted. There may not be enough of them to continually offset the acid effect of the rain. When nature can no longer buffer the effect, the balance is lost. This is what has been slowly happening for the past 100 years in the natural environment due to acid rain. The areas most affected by acid rain are those with shallow soil cover on slowly weathering bedrock (since beneficial alkaline substances are released as the bedrock is weathered by incoming rain). 

For example, igneous bedrock (e.g., the granite bedrock of the Canadian Shield that covers almost half of Canada) has a very low alkaline content and, therefore, can’t buffer the effects of acid rain. On the other hand, regions that are formed on limestone or sedimentary bedrock (e.g., southern Ontario and parts of western Canada), which contain high levels of calcium, can tolerate fairly high acidic deposits over long periods of time. Limestone is very alkaline, and so it can maintain an acceptable balance despite increased acidity.

Events Of Acid Rain In China

In China, acid rain has become a large problem. It cannot be denied –the effect of toxic rain is visible even on The Leshan Buddha. The giant statue that has drawn Buddhist pilgrims, tourists, and scholars for 1200 years is now discolored, its face appearing “sooty.” This is thanks to acid rain. Because of the statues importance in the culture, acid rain is no longer considered just an environmental problem, but also a threat to heritage. China’s highly industrialized society has resulted in this man-made pollutant, the highest concentrations of the problem being in southeast China where the most people, power-plants, and factories are located. The rain has received little international attention due to China’s many other environmental problems, but is a very serious problem. It not only erodes monuments, but also eats away at the outside of buildings, destroys paint finishes, poisons land (a problem for farming), and turns bodies of water into lifeless puddles. Acid rain also results in serious health effects including lung disease, heart attacks, and asthma. 

In 2001, Beijing implemented a national target for reducing SO2 levels in the 10th Five Year Plan (2001-2005). Beijing aimed to cut sulfur dioxide emissions 10 percent below that of 2001 by 2005, but instead emissions increased 28 percent. There is hope however. Between 2006 and 2009, China’s SO2 levels decreased by more than 13 percent. The government has begun to shut down hundreds of inefficient coal-run plants. Larger plants that have the money to install a more environmentally friendly method of production have done so. These plants are required to meet certain standards, as well as install SO2 monitoring systems. There are also monitoring systems to ensure the equipment is used appropriately. This is a key part of the plan to better the factories as using the inefficient equipment will increase production. Thanks to the monitoring systems, people know they cannot get away with using the old equipment. This national step of monitoring emissions, and making an effort to change, ultimately shows that China has adopted an ideology of being environmentally aware. Though there is still room for improvement. The systems implemented by the government are not perfect, and the country has a long way to go. Still, China’s recent change in thinking and acting is a reason for hope globally.

The article was presented from all sides. Acid rain and SO2 emissions (which are among the causes of acid rain) affect many different parts of China –from the basic wear and tear of buildings, to the poisoning of farmland and destruction of national monuments. This is a social problem because it is affecting China as a whole. It affects production, and industrialization, the well-being of the population (health and livelihood), the effort to preserve culture, etc.

The Effects of Acid Rain on Forest Nutrient Status

The effects of acidic atmospheric inputs on forest nutrient status must be assessed within the context of natural, internal acid production by carbonic and organic acids as well as the nutrient inputs and drains by management practices such as harvesting, fire, and fertilization. In all cases the anion associated with acid inputs must be mobile in the soil if leaching is to occur; immobilization of anions can effectively prevent from leaching. Soil acidification will occur only if the often substantial buffering capacity of the soil in question is exceeded by acid inputs and weathering from primary minerals is insufficient to offset losses by leaching. Such circumstances are rare but certainly could occur in theory, at least, given sufficiently large acid inputs on poorly buffered soils. Soils most sensitive to change are thought to be those of moderately acid pH and low cation exchange capacity. Neither very acid soils nor neutral, highly buffered soils are sensitive to acidification by acid rain.

Leaching of Nutrients

Hydrogen ions from the acid in acid rain replace the nutrient elements in the soil. For every unit of acid added to the soil, an equivalent amount of nutrient elements is removed. As a result, more nutrients get leached from the soil than arrive from weathering of rocks or precipitation

Extremely high acid inputs, acid rain can cause temporary increases in nitrogen mineralization and nitrification in soils. While temporary increases in N availability can cause increased forest growth in N-deficient forests, increased Al availability can cause toxic reactions in tree roots. Little is known about tree aluminum toxicity levels as yet, however. It must be emphasized that assessment of acid rain effects is a problem of quantification. Given sufficiently high inputs on sensitive sites, negative effects of acid rain must occur, as is true of inputs of any substance, including H2O. Acid rain inputs of sufficient magnitude to cause acute effects, such as growth increase due to N mobilization or growth decrease due to Al mobilization, are apparently very rare under ambient field conditions. Long-term effects on forest nutrient status can be either beneficial or adverse, depending on site nutrient status and amount of atmospheric inputs.

Neutralization

The effect of acid rain on the environment depends greatly on the ability of soils to neutralize the acid. Limestone and other rocks and soils containing calcium carbonate are most effective. Acids react with calcium carbonate to produce neutral compounds and carbon dioxide. Mature forest soils are also able to neutralize the acids in rain. Such soils are acidic. Krug (1983) reports that mature soils in New England or Norwegian forests have a pH of 3.8, and they may contain as much acid as would fall in 1000 years of rain at 1m/year with a pH of 4.3. These soils are highly resistant to acid rain.

In contrast, thin alpine soils lacking carbonates and  acid and overlying granite rocks are not able to neutralize acid rain. The same is true for disturbed forests where forest fires and logging have reduced the organic material in the soil, which also make the soil more susceptible to damage by acid rain.

Influence of Acid Rain on Tropical Rainforests

Tropical rainforests are the biggest forest area in the world. They constitute 6% of the whole area of the Earth and they have great significance in water and heat balance on our planet. What is more, these forests are home for the half of the species of plants and animals we are familiar with. They are a treasure trove of nature which acid rain threatens.

The main danger to rainforests is human's wasteful economy. The forest are cut own and burnt. The processes are mainly connected with industrialization and accordingly they carry acid rain threat which is local (burning - carbon dioxide, industry - sulphur dioxide and nitrogen oxides). Furthermore, omnipresent and very mobile cloud and air pollution also do not omit the tropics. Even rain acidified to a very small degree whose whole total yearly fall is from 1000 to 2000 mm, destroys ever-green tress whose vegetation period lasts a whole year.

Effect of Acid Rain on Sculptures and Buildings

Acid rain is caused by pollution in the atmosphere bonding with water droplets. The pollution itself is normally sulphur or nitrogen dioxide. These compounds combine with water in the atmosphere, fall as acid rain and enter the general water supply. Initially it is more harmful to plants and animals, but this rain can have devastating effects on older buildings and statues made from certain types of stone.

Statues and sculptures

Older statues, especially those made of marble and limestone, are especially vulnerable to acid rain. This is because the rock contains large amounts of calcium carbonate, which reacts with the acids in the rain. This can cause the stone to turn to gypsum and flake off, ruining the detailing. This effect is cleaned off many statues, but can be regularly seen in graveyards where the headstones show the same erosion effect. Bronze statues are also at risk as the acid oxidizes in the metal causing corrosion.

Buildings

Due to what they are made of, buildings are less affected by acid rain. Older buildings with limestone or marble modeling on the outside can suffer from the same problem as statues. In addition, metalwork within the structure, such as copper pipes and wiring, can oxidize if exposed to acid rain.

The more obvious impacts of acid rain can be seen on particular types of stone, such as limestone and marble buildings, monuments, statues and headstones.  The weathering pits and canyons can obliterate the lettering and features of such structures to a brutal degree, depending on the type of stone and other environmental conditions.  Acid rain can also corrode bronze and other metals, such as nickel, zinc, copper, and carbon-steel as evidenced by streaks and discoloration on bridges and other metal structures, such as many commercial buildings. 

Not all buildings or structures suffer the effects of acid rain.  How big of a threat it is can be determined by the chemical makeup and  interactions of a building's materials.  Limestone and marble, which, historically, were used widely because of their availability and workability by artisans, are especially susceptible because they are composed of calcite, or calcium carbonate, which acidic chemicals can dissolve easily.  To observe this first-hand, drop a piece of blackboard chalk into a glass of vinegar.  Drop another piece of chalk into a glass of water.  The next morning, you’ll see the alarming difference.

Modern buildings tend to use granite, which is composed of silicate minerals, such as quartz and feldspar.  Silicate minerals resist acidic attacks from the atmosphere.  Sandstone, another silica material, is also resistant.  Stainless steel and aluminum tend to hold up better.  But all minerals, including those found in paint and road overlay, are affected, to some degree.
Because of the switchover in the use of certain building materials in the post-Industrial Era, historic buildings, more so than modern ones, tend to show the destructive outcome of acid rain since we first began burning fossil fuels for energy.  London’s Westminster Abbey, the Colosseum in Rome, and India’s Taj Mahal all show signs of degradation brought on by atmospheric nitric and sulfuric acids.

Prevention from deterioration

 One way to reduce damage to monuments and statues by acid rain is to use materials that are known to be acid-resistant. Granite is known for its durability and has been traditionally used for flooring and surfaces that are regularly exposed to acidic substances, including kitchen counter tops. It now is increasingly replacing marble and limestone in the manufacturing of monuments and sculptures. The metal manufacturing industry has developed several new materials that prove to be more acid and corrosion resistant than the traditional products. Other protective measures are acid-resistant coatings and resins that protect stones and metals from the penetration of acid rain. In the meantime, the Environmental Protection Agency (EPA) has developed an Acid Rain Program that aims to reduce sulfur dioxide and nitrogen oxides emissions that cause much of the damage to the monuments and sculptures. The program imposes annual emissions limits on industrial plants that produce most of the harmful substances.

Effect of Acid Rain on Lakes and Rivers

It is in aquatic habitats that the effects of acid rain are most obvious. Acid rain runs off the land and ends up in streams, lakes and marshes - the rain also falls directly on these areas.As the acidity of a lake increases, the water becomes clearer and the numbers of fish and other water animals decline. Some species of plant and animal are better able to survive in acidic water than others. Freshwater shrimps, snails, mussels are the most quickly affected by acidification followed by fish such as minnows, salmon and roach. 

Lakes, rivers and marshes each have their own fragile ecosystem with many different species of plants and animals all depending on each other to survive. If a species of fish disappears, the animals which feed on it will gradually disappear too. If the extinct fish used to feed on a particular species of large insect, that insect population will start to grow, which in turn will affect the smaller insects or plankton on which the larger insect feeds.

Life of Aquatic Organisms:
 
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. Generally, the young of most species are more sensitive to environmental conditions than adults. At pH 5, most fish eggs cannot hatch. At lower pH levels, some adult fish die. Some acid lakes have no fish.

The roe and fry (eggs and young) of the fish are the worst affected as the acidity of the water can prevent eggs from hatching properly, can cause deformity in young fish which also struggle to take in oxygen.The acidity of the water does not just affect species directly, it also causes toxic substances such as aluminum to be released into the water from the soil, harming fish and other aquatic animals.
 
Makes Drinking water unsafe:

Water that is slightly acidic should not be dangerous, as there are many foods that have low pH
value; for example, lemon juice has a pH of 2.4. However, a low pH can indicate that there may
be other contaminants in the water, because if pollutants have been added to a water source,
the pH typically will change.

Water treatment facilities monitor the pH level of the water while they are treating it for
municipal use. Acidic or basic water is harder to disinfect than water with a pH that is closer to
7.0. As well, if acidic water was sent through pipes and into homes, there would be a greater
danger of pipe corrosion, which could allow metals to dissolve into the drinking water as it flow
through the pipes. According to the World Health Organization, a pH less than 8.0 is necessary
for effective chlorination. If the pH is too high, water treatment facilities can decrease the acidity
in a number of ways. One common method that is used to increase the pH is to send the water
through a calcium carbonate filter, which neutralizes the acid and increases the pH of the water. Another common method is to inject a sodium carbonate solution into the water.

Effect of Acid rain on vegetation

Many scientists now believe that the direct and indirect impacts of acid deposition on vegetation are substantive, whether these effects are measured in a biological or an economic context.The growth rate of spruce trees in the Green Mountains of Vermont declined by 50% between 1963 and 1973.Tree ring analysis suggests similar reductions in forest growth in Europe. Acid precipitation has been implicated in these declines, but unambiguous cause effect relationships are lacking. 

Factors

In addition to the extent of acid deposition (concentration or total deposition), the response of plants to acid deposition will depend on a number of factors including:

• Plant species, ecotype or cultivar.
• Plant age or stage of development.
• Characteristics of exposure (frequency, duration, period, form of acidity, time between exposures, and others).
• Other environmental factors that affect plant vigour.
• Buffering capacity/sensitivity.
• To address these challenges, many scientists have resorted to research in controlled environments such as greenhouses or growth chambers, using simulated acid precipitation.

Direct effects of acid precipitation on plants:

The acid rain affects the crops as well as the vegetation. The effect of acid rain on plants is grave. It not only damages the root, but also stops its growth and brings an end to the life of a plant. The nutritive value of the soil is reduced to a great extent as an effect of acid rain. Acid rain effects can be seen on the useful micro organisms which convert the decayed organic matter into essential nutrients for the soil. The consequence is that the micro organisms are killed resulting in reducing the availability of nutrients for the soil and plants. Also, the waxy layer of the leaves is damaged which make the plant more and more susceptible to diseases.

The havoc done by acid rain is not localised in the place where it is caused. The atmospheric emissions may travel for several days and over long distances depending upon wind and climatic conditions, before coming down as acid rain. The problem caused in an industrialised area may therefore result in acid rain in the surrounding forests or lakes, or even further away. It is believed that around 50% of the acid rain that occurs in Canada is due to pollution caused in the United States of America, and the effect of polluting industries in England can be felt in Norway