Answers to Questions About Abbreviations

Answers to Questions About Abbreviations Answers to Questions About Abbreviations Answers to Questions About Abbreviations By Mark Nichol Responses to some reader queries about abbreviation issues follow. 1. Which is the preferred abbreviation for â€Å"United States,† US or U.S.? Both forms are correct, but, in the interests of consistency with the decline of the use of periods in abbreviations, the trend is to use US. (Note that the abbreviation should be used only as an adjective, not as a noun: â€Å"She was born in a US territory,† but not â€Å"She was born in the US.†) 2. When one abbreviates states, should there be any punctuation after, say, TX? And are both the T and the X capitalized? The short form of state names based on US Postal Service usage and technically considered a symbol rather than an abbreviation omits periods, and both letters are capitalized. However, the symbol should be used only when listing an address or in a chart or other graphic element where space is at a premium. Newspaper style is to abbreviate according to The Associated Press Stylebook (for example, Tex.), but in many other periodicals and in most books, state names are usually spelled out in regular text. 3. I am teaching a business-writing course, and I want to know how to approach terms like SOP or any other abbreviation. Does one say â€Å"an SOP† or â€Å"a SOP†? I guess the same would apply to â€Å"getting a MA† or â€Å"getting an MA.† Because we pronounce each letter in these terms (â€Å"ess-oh-pee† and â€Å"em-ay†), rather than treating them as words (â€Å"sop† and â€Å"mah†), the first sound determines whether we use a or an when we speak or write the abbreviation. As with other words starting with the â€Å"ess† sound (especially or essential, for example), we precede SOP with an. The same goes for MA, just as in, say, eminent or embellishment. Testing phrases vocally is usually reliable (an seems easier to say before these terms than a does), though there are exceptions: â€Å"An historic occasion† is easier for me, at least to say than â€Å"a historic occasion,† though an is â€Å"wrong.† See this post for more information. Want to improve your English in five minutes a day? Get a subscription and start receiving our writing tips and exercises daily! Keep learning! Browse the Style category, check our popular posts, or choose a related post below:Yours faithfully or Yours sincerely?7 Patterns of Sentence StructureParataxis and Hypotaxis

7 Steps to Finding Success If You Drop Out of College

7 Steps to Finding Success If You Drop Out of College Think you can’t be successful if you drop out of college? Think again. Some of the biggest companies in the world were started by entrepreneurs who never finished school. While there are skills and experiences and accomplishments that any aspiring successful person will acquire in college, if you happen not to have finished (or you find yourself having dropped out and spiraling in a fit of panic), remember that it isn’t necessarily the end of the world. Here are a few things you can do if you dropped out to get yourself back on a good track to success.1. Breathe.First take a deep breath and realize it’s your life. You are in control. If this is what you need and you can still accomplish what you want to in life without this degree? Then great. Start making concrete plans and working towards that goal.2. Keep learning.Education doesn’t necessarily end with school. Neither should yours. Continue learning as voraciously as possible- following what interests y ou most and what you’d need to know to expand your career outside of school. Don’t fall into ignorance or stagnation just because you needed to stop attending college.3. Keep taking risks.Dropping out to pursue other options is a big risk. If it pays off for you, continue thinking of other ways you can take calculated risks in pursuit of your destiny. Keep pushing for your dreams. You’ve already shown you have the guts. Persist!4. Find your real-life community.Just because you aren’t in college anymore doesn’t mean you don’t need professors and â€Å"classmates.† Find yourself mentors. Present yourself to people in your desired field  and show your willingness to learn. You’ll probably get a good recommendation out of it at some stage in your career. Similarly, find your crew of like-minded, similarly-oriented people who you can build your empire (or at least a business) with. Learn from each other and promote each other†™s work.5. Don’t ditch responsibilities.Whatever your new class equivalent is- show up for it. Don’t blow things off just because you aren’t technically required to show up anymore. Push yourself and give yourself grades! This is equally important for work. Get a job and show up at it- on time and consistently.6. Don’t be defensive.You can’t have it both ways. If you didn’t finish school, you can’t very well complain that other people did and it makes you feel bad. Remember you chose your priorities and your life. It was your choice. Be honest about why and don’t take any negativity  from anyone if they react unfairly.7. Be humble.Be willing to work from the bottom up. Get in on the entry level of whatever field you most want to work in. Be willing to start low on the totem pole. With a little humility and dedication, you probably won’t be down there long.

Conducting Situational Analysis Assignment Example | Topics and Well Written Essays - 1750 words

Conducting Situational Analysis - Assignment Example It involves understanding the main competitors of the firm and has a detailed analysis on how innovative they are, factors that affect them, how their products are perceive relative to your own and finding the niche markets that are not served. Segmenting the market is useful when a company needs to serve its customers efficiently since it enables pooling of needs of customers and finding the best way to satisfy them. Market segments can be identified based on demographic, psychographic, behavioral or geographical factors. It will therefore be easy for a company to formulate and implement position strategies that will help sell the product to potential customers. Table of Contents Executive summary 2 Table of Contents 3 Background 4 Company products 4 Situation analysis 4 Strength 5 Weakness 5 Opportunity 6 Threats 7 Customers 7 Main competitors 8 Market segments 8 Position strategies for the market segments 9 Reference List 11 Background Richer Sounds was established in 1978 by Juli an Richer at a tender age of 19 years. Before this age, he begun the business at an age of 14 years where he specialized in buying and selling hi-fi separates music system. Under support of Vic Odden- a photographer retailer-made a start of a journey into the most successful retailer in UK. The retail received an award in 2002 being the best British-owned company that provides best working conditions for its workers. The company is operating at 52 stores in secondary high street locations in UK. Since its growth, the company has been able to invest in people schemes and in 2010, it received an award of the Best Retailer Award (Richer Sounds PLC, 2012). Within its operation, the company has kept providing value to its customers and requesting them to fill questionnaires regarding how best they have been served and performance quality of their products. The period 2009 to 2010, the company was able to realize a profit of 5 million pounds which was from a turnover of 160 million pounds . Company products Richer Sounds has become a national retail stores. The current demand in the market required Richer Sounds to provide most of the best latest flat-screen TVs, hi-fi, DVD and electrical appliances. Situation analysis Richer Sounds has placed much investment in product advertisement to reach its customers and increase its market share both in the existing market and its potential markets. The company has been able to make an analysis of its strength weakness, opportunities and strength to assess its position in the market and ability to serve its customers (Thompson and Martin, 2010). Strength Richer Sounds enjoys a long lasting characteristic of providing quality products and services as they keep the fun for their customers. Awarded as the best high street retailer, it remains to b the UK bets value hi-fi, home cinema and TV specialist. This makes them call their brands as the biggest with best prices. The company is organized in a way that it offers expert servic es to its customers. Its strength has been its brands of high quality hi-fi and electrical appliances which the customers have come to accept as best in satisfying their

Short Story fiction Essay Example | Topics and Well Written Essays - 1000 words

Short Story fiction - Essay Example After leaving Red Sammy’s place, Grandmother throws a tantrum in order to be taken to a plantation nearby that she had known long ago. Bailey agrees to divert into the way in which his mother shows him. The grandmother realizes she has lost all recollection of the plantation. They drive back when they fail to trace the plantation. Grandmother’s cat jumps out of its box and lands on Bailey’s shoulder. Bailey loses control of the car and off the road. The car flips and plunges into a ditch. Just then, another car approaches them, and three men climb out. These men are The Misfit, Hiram, and Bobby Lee. The grandmother recognizes the Misfit, and he is unhappy with the fact that somebody recognizes him (Kilcourse 73). Grandmother tries to flatter the Misfit, but as it turns out, he is the hard-to-please kind. He orders Bobby Lee and Hiram to take John Wesley and Bailey into the forest. A moment later, Bobby Lee and Hiram shoots and kills them in cold blood. Grandmothe r fears for her life and she resorts to her Christian faith for the hope to live through the moment. The Misfit puts on Bailey’s shirt that Bobby Lee and Hiram have brought to him after killing Wesley and Bailey. Grandmother pleads with the Misfit not to kill her and advises him to pray to Jesus. In a matter of seconds, the Misfit shoots the grandmother thrice in the chest. Hiram and Bobby Lee come back from killing The Mother, June Star and the baby. The Misfit remarks that there is no pleasure in life (Kirk 39). Analysis of A Good Man is Hard to Find The title of the book, A Good Man is Hard to Find, points to Red Sammy Butts in the moment he conversed with grandmother while at The Tower. Mistrust of others is a theme that is consistently evident in O’connor’s book. In their conversation, Red Sammy Butts and grandmother confirm this. They reckon that it is hard to trust anybody in the world. Red Sammy recounts how he allowed two men to take gas on credit, and he laments ever having to be good to people (Robillard 52). Grandmother believes that there is not even a single soul on earth that can be trusted. This contradicts the Christian faith to which the grandmother is a strong believer. In this book, O’connor presents the reader with two clashing moral codes. Both grandmother and the Misfit have beliefs and perceptions that guide their conduct. A moral code is a collectivity of people’s behaviors, and beliefs thought of as reasonable and acceptable. The rightness of a person’s moral code is subjective. At a glance though, one would not help but notice how the Misfit’s code is erroneous. Grandmother’s code is also contradictory and unconvincing (Hardy 48). It is clear that grandmother’s moral code derives from what she thinks is good. For example, she emphasizes the importance of looking like a lady, depicting that she is more interested in appearance than in substance. She subtly deceives Bailey and the whole family without remorse. Despite her claim of Christian piety, she cannot even remember to pray when in a crisis. She even dares to question the divinity and power of Jesus. On the other hand, the misfit is consistent and apt in following his moral code. The Misfit believes that punishment is always bigger than the wrong done, and in the end, the wrong done does not receive the emphasis it deserves. It is clear that religion baffles the Misfit. Whilst the grandmother took faith blindly

The Maori Religion And Rituals Of Various Cultures Religion Essay

The Maori Religion And Rituals Of Various Cultures Religion Essay This essay discusses the Maori religion and variety of culture of the indigenous Maori community. It also discusses the death rites and the rituals of various Maori cultures, for instance, the marriage, death and birth rites and rituals among others. Starting with the rich Maori religion Russell (2006) points out, that the Maori people believe in the existence of spiritual beings and a supreme supernatural being called lo. They believed that lo is only revealed to those who have reached a particular level of class preferable the most learned in the Maorisà ¢Ã¢â€š ¬Ã¢â€ž ¢ society. But all of them regardless of class or age believe in the existence of eight gods whose parents are called Rangi and papa. There is gods of the forests and the forefathers called Tane. There is the god of sea called tangaroa. There is the god of agriculture and peace known as rongo. They also have god of weather and god of the uncultivated food known as Tawhitimateo and Haumia respectively (Keith, 1980). The Maoris also have god for earthquakes that is called Ruaumoko .Their belief in the existence of darkness and evil makes them to believe in the existence of the god that caused the same known as Whiro (Russell, 2006). There is also a special god for war who is also responsible for the invention of the snares and digging sticks. On the other hand, each Maori tribe had a special god for war. The gods for war were useful when the tribes went for war. Apart from the war gods, each Maori family had family gods and spirits. The family spirits had their origin from the dead, abortions or miscarriages (Siers, 1976). In the Maori religion there is association with the visible symbols that has a natural phenomenon. These symbols are the rainbow, the comets, trees and even stones. Living creatures such as birds, fish and lizards also have a connotation in their religion. There is also carving of gods either from sticks or stones that are worshipped. The Maori have god families. Another important aspect of the Maori culture is on the death and funeral rituals. The dead body that is known as tupapaku is traditionally preserved and kept in a special meeting place called marae. The body has to stay for three consecutive days in this house and the body is never to be left alone even though the coffin is usually left open till the burial day. The mourning period is occasioned by wailings from the women and speeches are made in Maori language (Keith, 1980). Orupa that is the cemetery is adjacent to the marae. According to Siers (1976) those who view the body are required to wash their hands afterwards using water or bread that is usually at the exit In Maori culture the burial and funeral rituals of important people are carried with pomp as they believe that these people will send protective spirits afterwards. For example, the death and funeral ritual of a chief is characterized by immense decoration of the body using feathers. The skulls of the enemies are placed at the feet, while all the remains of the ancestors are put at the head. On the poles next to the body there is heads of the enemies. During the mourning period, relatives of the dead are not allowed to touch food using their hands but they are fed by their relatives, friends or members of the tribe. They just have to open their lower jaws and food tossed into it. In showing their sorrow people cut their bodies using shells and the profound bleeding is symbolic for the immense loss incurred by the bereaved (Russell, 1996). According to Keith (1980), on the burial day the chief have to be buried with all things that are valuable in the Maori community. He also points out that, the burial of the dead does not end with the first burial but there is the second burial known a secondary burial. In the second burial, the remains of the dead are removed from their primary burial place. These bones are then cleaned and painted with red ochre. The remains are then taken from village to village for a second mourning and later buried this time round in a sacred place (Keith, 1980). Another important culture among the Maori is the welcoming culture that is characterized by a number of rituals. This culture was called marae by the Maori people (Siers, 1976). During this ceremony women perform oratories called karanga. According to Keith (1980), the karangas are done in Maori language and these oratories are both educative as well as entertaining. Russell (1996) says that, after the karangas there are formal speeches from the host. These speeches are known as whaikorero. A song called waiata is sung by various groups immediately after the speeches. Gift giving is another important occasion during the welcoming culture. The gifts also known as koha are given out followed by karanga. Russell (2006) points out another symbolic ritual in the welcoming culture as the pressing of the noses, also known as hongi which is a sign of appreciation. To mark the end of the ceremony, a meal called hakari is usually shared (Siers, 1976) According to Keith (1980) the third culture with rituals in the Maori community is the marriage and wedding ceremony. In choosing partners members of the opposite sex can either choose their partners or the partners chosen for them by the elders. But the female can turn down the advances of the opposite sex by putting a mark on their forehead called atahu. Courtship generally varied in the Maori culture in that, some tribes simply proposed by capturing the potential bride. This tactics sometimes turn violent. In Maori marriage, adultery was heavily punishable. The punishment was in form of plundering the homes of the couple. Divorce was not ruled out. It was ritually carried out using water (Siers, 1976). The wedding usually takes place in the marae and during this ceremony a relative of the groom challenges the father of the bride to come forward for a fight. The father of the bride approaches the relative of the groom as if he is ready for a fight but instead stretches his hand and greets the challenger (Keith, 1980). Another culture of the Maori is the birth culture and the rituals that accompany it. Russell (1996) says that, the Maori women control the birth process but it is the midwives known as the tohunga who have control on the conception, abortion, birth and parenting. The women has to follow strict guidelines from the tohunga and during the delivery time, women deliver either in squatting or standing positions with minimal support offered on request. The Maori women either gave birth in an open place away from the main dwelling or in a temporary structure made for the same and were burnt at the end of it. This temporary structure was called whare kohanga or simply the nest place (Keith, 1980). The nest place was meant for high ranking women on their first deliveries. The placenta is usually buried. According to Siers there is an important ritual rite called tihe that is usually performed during child birth. It is a form of baptism that resembles the modern mode of baptism in Christianity. In most cases, there is chanting and singing to welcome the newborn baby. Gifts are also given out by the family members. Giving the Maori culture without giving the type of food, their economic activities, clothing and the traditional Maori culture will not make the discussion on the Maori culture, religion and rituals complete, therefore these aspects will be mentioned on the preceding paragraphs. Keith (1980) points out that, the economic activities of the Maori culture vary with the location. He says that they are hunters, gatherers, and farmers. They hunt birds such as pigeons, ducks, and rat among others. Those that live along the coastal lines hunt grubs, earthworms, fish, shellfish, and sometimes whales. The Maoris use dogs for hunting purposes and the Maori are said to be cannibals thus thy also survived through eating each other (Keith, 1980). Russell (1996) says that on art, the Maori has paintings and weavings mostly done by women. The indigenous Maori is characterized by group performance called kappa haka. There is also oratory that is authentic and has both entertaining and educative influence. The clothing is accompanied with tattooing of faces where women tattooed their lips and chins a method called ta ngutu. The tattooing was done either through piercing or pigmentation of various body parts (Keith, 1980) Siers (1976) says that in the traditional Maori culture, society is segregated into small villages called kainga. These villages contain members of one of more members of a tribe usually called hapu. The kainga varies in sizes depending on productivity and population density of the regions. There are also villages that are fortified called pa. Each village has a store called pataka where war weapons, fishing gear and preserved foods are stored. The villages also have well decorated houses called whare whakairo which were for indoor meetings and entertainment of guests In conclusion the rich indigenous culture of the Maori has been greatly influenced by modernity leading to some aspects being eroded. Has a result the Maori culture and religion has changed in the recent past (Keith, 1980).

Bribery: Tammany Hall Essay

Political machines of fraud and bribery Introduction: Lincoln Steffens published the â€Å"shame of the cities† witch was a book based on the corruption in the 1900’s. By 1900, many cities in the south of America were controlled by political machines. These organizations consisted of full-time politicians whose main goal was to get and keep politicians power and money and also influence that went into it. In the 1900’s, machines were usually associated with a political party; party’s forced to join to limit competition. And although it provided aids it also stifled opportunities for many citizens. Political bosses controlled access to city jobs for example police and fire departments or on contraction projects. To get a city work contract you had to donate to the machines reelection campaign. Many business paid politicians make government not to interfere with their activities. Such payoffs became part of the cost of doing business. Muckrakers called them BRIBERY National government also suffered from corruption. For example, the constitution gave state legislatures the power to choose senators, but corporations often bribed state legislators to elect their favored candidates to the senate. The senates were really wealthy men with class ties to powerful industries. As cities and their problems grew rapidly the political environment changed. No longer did politicians run small manageable cities. These were big cities with big city problems and the government structures designed to cope with these problems grew. As the government grew it became the livelihood for many professional politicians. Some would argue that these politicians were corrupt, they would argue that they provided a needed service . he Society of St. Tammany, which was also called the Columbian Order, was founded in May 1789 (some sources say 1786). The organization took its name from Tamamend, a legendary Indian chief in the American northeast who was said to have had friendly dealings with William Penn in the 1680s. The original purpose of the Tammany Society was for discussion of politics in the new nation. The club was organized with titles and rituals based, quite loosely, on Native American lore. For instance, the leader of Tammany was known as the Grand Sachem, and the club’s headquarters was known as the wigwam. Befor long the Society of St. Tammany turned into a distinct political organization affiliated with Aaron burr, a powerful force in New York politics at the time.

Acid rain

The French chemist Ducros first used the term ‘pluie acide' in 1845. The phraqse ‘acid rain' ,was brought in 1872 by Robert Angus Smith (Wellburn, 1994). Back in fifties, there were observations of lakes in Scandinavia losing their fish populations. Anglers and naturalists noticed that fish stocks in many lakes of southern Scandinavia were diminishing. Freshwater acidification had rapidly worsened over a few decades. Although acid rain and the acidification are a not new problem that has received considerable attention for many years, it was not until 1960s that scientists were able to link these effects to any specific cause. Later it was found to be atmospheric pollution. Acidification is not a regional phenomenon. In Scotland, studies show that the acidification began around the middle of the last centuries and the process has accelerated in the last three decades. In southern Norway, It has reported that 87 lakes had a pH below 5.5 (Mason, 1996). Damaged forests were becoming widespread in West Germany. As these examples show, acidification is an international problem. Pollutants may be carried with winds over distances, from points hundreds or thousands of miles away. Some countries are net importers of pollution, and others are exporters. The effects of acidification are varies, not only pollution of lakes and forests as previously mentioned, but also effects on fauna and flora, soil, groundwater and direct or indirect harm on human health, and all things are influenced by water quality through hydrological pathway (Thunberg, 1993). The aim of this report is to discuss causes and effects of acidification that has been concerned until now, and present possible short-term and long-term soluti on to acid deposition effects on water quality 1. Acidification and its causes Airborne pollution can influence the environment both directly and indirectly. Primary pollutant is Sulphur dioxide and nitrogen oxides. When these are present in high concentrations, they can cause damage on environment and human's health. These direct effects are often peak in the vicinity of the emission sources. Industrial society discharges suphur dioxide and nitrogen that form sulphuric acid and nitric acid, which may be carried with the winds over long distances before descending in rain or snow. Indirect effects often occur as acidified soil and water far away from the sources of emission (Thunberg, 1993). There are gas-phase reactions, which produce acidity in the atomosphere. Sulphur dioxide and nitrogen oxides form suophuric and nitric acids on coming into contact with water. When these acids reach the ground in rain and snow, it is called ‘wet deposition'. However, acid oxides may also be deposited directy as gases, or cles, which is called ‘dry deposition'. The rates of dry deposition velocity may depend on the nature of the land surfaces. Rates of wet deposition depend on the precipitation rate, the washout ratio of dissolved pollutant per unit mass of cloud water or rain divided by the concentration of the same pollutant per unit mass of air (Wellburn, 1994. A low pH value means a high level of acidification. Water in neutral condition has a pH of 7 (Thunberg, 1993). Sulphur and Nitrogen Cycles are presented below (Figure 1 and 2). Figure 1. Sulphur Cycle Source: ICU (2003) Figure 2. Nitrogen Cycle Source: ICU (2003) 1.1 Sulphur Sulphur compounds are responsible for about two-thirds of the acidification of rain. Sulphur in gaseous form, sulphur dioxide (SO2), is mainly formed in the combustion of oil and coal. The rapid increase in emission of pollutants came after the war followed by consumption of fuel and oil. It was reported that approximately 20 million tons of sulphur are now emitted every year in Europe. There is also a great deal of airborne pollution in North America, where about 12 million tons of sulphur is released every year. Sulphur can be formed by naturally by eruption of vulcanoes, from seas and oceans and certain processes in the soil. However, 90 per cent of the emissions of sulphur to the atmosphere are derived from industrialised parts of Europe and North America. This is ten times the level that can be considered natural (Thunberg, 1993). 1.2 Nitrogen Nitrogen oxides (NOX) are grouped term of nitrogen monoxide (NO) and nitrogen dioxide (NO2). Nitrogen oxides are formed in all types of combustion, most of the NOX are formed by the reaction of nitrogen gas in the combustion air with oxygen. When the mixture of nitrogen gas and oxygen is heated, they interrelate to form NOX. The higher the combustion temperature, the more NOX will be formed. The largest source of NOX emission is road traffic. These emissions are reported to have doubled during the 1960s, approximately 22 million tons of NO2 are released every year in Europe. Certain types of fertilizer are another source of nitrogen pollution. Nitrate leaching intensified the acidification of the soil, which release unwanted substances such as aluminium (Thunberg, 1993). 2. The environmental effects of acidification 2.1 water acidification and aquatic biota Acidification was first noticed in the lakes. The initial victims of acidification are nutrient-deficient lakes in areas where the soil has a poor buffering ability (Thunberg, 1993). It is reported that many lakes in the Rocky Mountain have little alkalinity to buffer increase in acid deposition, however loss of alkalinity has been observed caused by high concentration of acid deposition due to the emission in the Rocky Mountain region (Turk et al, 1989). Figure 3. Acidified lake: A deep blue colour of a lake is a sign of acidification. Source: ARIC (2000) In severely acidified lake, the fish will have vanished entirely, bog moss will have spread out over the lake floor, and only few plant and animal species will remain. The first victims of acidification are crayfish, snails and mussels, certain types of zoo- and phytoplankton, and some species of mayfly. Usually, certain types of bog moss and insects those are resistant to acidification remains. This is not only low pH value that takes a heavy toll of fauna and flora. In acid lakes there are increased concentrations of aluminium in ion form, which is highly toxic to many organisms. The loss of fauna / flora is due to the combination of a lowered pH and aluminium poisoning. The level of other heavy metals also rises such as cadmium, zinc, and lead. Those heavy metals including aluminium flow into lakes from the acidified soils of the surroundings. The relationship of prey and predators will also change, for instance certain insects on which they usually prey begin to thrive when their predators are disappeared (Thunberg, 1993). 2.2 Soil/water interactions Acidification process takes place naturally in the soil. The plant releases hydrogen ions as it uptake nutrients. Though the growth itself is acidifying, there is no net acidification where growth and decay are about equal. However, the cycle is broken by harvesting, the acidifying process will take over. Soil acidification may have biological effects in the respects through lowering of the pH value, an increase in the levels of aluminium and other toxic compounds and a loss of plant nutrients due to increased leaching, consequently may lower drainage water pH (Thunberg, 1993). Moreover, Long-term increase in nitrogen supply may be responsible for alterations in root and shoot growth of plants(Carrol et al, 2003). Figure 5. Soil pH range source ANRA (2003) 2.3 Effects of forestry practices Forestry practices can cause the soil and water to become acidified in several ways. Forest growth change drainage water pathways to stream, and increase stream water acidity. Extensive clear cutting can also accelerate the acidification of surface water. Applying acidifying fertilizer also helps to acidify soil and water (Thunberg, 1993). Twelve years studies of acidification-induced chemical changes in soils of Norway spruce and Scot pine in southern Sweden reveals that pH in mineral soil decreased on average 0.17 units between 1988 and 1999. It is said that these changes in forest soil are mainly due to the extensive deposition of acidifying substances (sulphur and nitrogen compounds) during the latter part of the 20th century (Jà ¯Ã‚ ¿Ã‚ ½nsson et al, 2003). In addition, atmospheric pollution directly damages forest itself. Since the early 1970s, West Germany has experienced a rapid and widespread decline in the health of its forest trees; especially sensitive species were affec ted by exposure to low levels of pollutants (Ling et al, 1987). 2.5 Groundwater quality Most of the precipitation sinks to some extent into the ground. The more permeable the soil, the more water dribbles down. Normally acid rain will become less acid as it penetrates through the ground. However, where the soil becomes acidified and has less ability to neutralize, the effect will be decrease until it finally ceases. It is unlikely that acid groundwater will be harmful to human health, however toxic heavy metals, such as aluminium and cadmium may appear at elevated level where highly acidic. These metals are harmful for human health (Thunberg, 1993). 3. Solutions Solutions to the problems of acidification fall into two groups, which are cure and prevention. Remedial measures can be applied where the problems actually arise (i.e. soils and surface waters). Preventive measures can be applied at source (i.e. at point of emission of the sulphur and nitrogen oxides). The latter are expensive and the least acceptable to industry, however they are in fact more effective, more sustainable, and more immediately required (Park, 1987). Causal treatment by reducing aciditying emissions is the primary goal in a long-term as preventive measures, however outcomes from this approach are still uncertain and recovery may be slow. Indicative treatment, involving the addition of neutralizing agent such as powdered limestone to affected environment is the only realistic remedy in the short-term, and has become a widespread practice in Europe (Thunberg, 1993). 3.1 Short-term solutions Remedial action should be taken after the problems happen. This requires not simply the elimination of symptoms of damage (i.e. restocking fish in acidified lakes, planting new trees); it also involves restoration of natural chemical balances to ensure that damage does not reappear. Some materials in nature have ability to buffer, or neutralize, or offset acid input. Lime and limestone are the most accepted of a range of chemicals that can be used to buffer acidic materials. Lime has been added normally by spraying from helicopter to catchments, soils and forests to alleviate damage and improve conditions for environment (Park, 1987). With regard to the lakes and streams, this raises pH value of the water and decrease in the levels of heavy metals. After the liming many species quickly return to their former habitat (Thunberg, 1993). This approach has been most widely investigated in Sweden (Park, 1987). This measure had been made in UK as well. Stream chemistry and biological effect was monitored for 10 years after the catchments of three acidified Welsh streams at Llyn Brianne were limed in 1987/88. This monitoring reveals that chemistry in treated streams changed significantly as mean annual pH increased from 5-5.1 before liming to 6.1-6.2; mean annual aluminium concentrations decreased from 0.15-0.18 to 0.05-0.11 mg L-1, and calcium concentrations increased from 0.8-2.0 to 2.4-4.5 mg L-1. The abundance of Acid-sensive taxa in limed streams increased after treatment. Liming has also been used as a means of restoring acidified soils. This improves the productivity of croplands and forests. However, liming can cause negative impacts on stream, such as fine CaCO3 deposited on the stream banthos. In addition, liming is an expensive ‘cure' measure. Sweden spent approximately $10 million from 1980-1983 for liming. Moreover, it is not practical for many lakes and rives, for some streams it is no help at all. There is uncertainty in relation to the effect of liming in a long run. Many studies have undertaken for the effects of post liming over short timescales, yet little has known about the long-term effects. At least 10 years monitoring is recommended (Bradley et al, 2002). Liming is a interim measures that provide biological defence, however it does not attack the root caused of the problems. It has been said that ‘a sort of artificial respiration for dead lakes and streams'. Therefore, real effective measures are long-term prevention deliberate through a sustained policy, rather than cure. 3.2 Long-term solutions The only way to solve the problem of acidification in the long run is to reduce emissions of pollutants. The central point of the political debate over acid rain is the need to reduce rainfall acidity by controlling emission of SO2 and NOX at source, mainly from power stations and vehicles: Reducing emissions of SO2 from power stations by: > Burn less fossil fuel > Switch to low-sulphur fuel > Fuel desulphurisation > Sulphur reduction at combustion > Flue gas desulphurisation > Disperse flue gases Reducing emission of NOx from power stations by: > Reduce NOx emissions during burning > Reduce NOx levels after burning Reducing emissions of NOx from vehicles by: > Modify engines or exhausts to reduce emissions > Change to different type of engine > Transport planning It is said that technology of controlling and reducing such emissions already exist. Some methods should be applied separately or in combination to be able to bring reduction to agreed levels within agreed time-scales. However, this problem is not only to do with a technical one. Political goodwill is essential as this measures involves high cost. All the cost should be offset by positive side-effects such as the creation of new jobs and generation of useful by-products (i.e. commercial sulphuric acid), the values of conserving fish, forest and crops, and benefits in improved human health (Park, 1987). In recent decades, there have been national and international efforts to achieve reduction in emissions of sulphur and nitrogen compounds to the atmosphere (Ferrier et at, 2001). As previously mentioned, emissions of sulphur and Nitrogen are carried by air and deposited as gases and aerosols and dissolved in rainwater, in areas far from their sources. The quality of air is very much influenced by emissions in others, so it will benefit little for any country alone to reduce emissions. This is called transboundary Import-Export Budgets. Data for 1998 is presented in Appendix A Without international cooperation, there can be no real solution (Thunberg, 1993). The details of these treaties and protocols are presented in Appendix C 4. Improvement Recent data shows that both emissions seem steadily declined particularly after these treaties and protocols noted above have adopted (See appendix B). However, compared to reduction of SO2 emission, NOX emission need to be reduced further, especially U.S, whose emission has not been much reduced. Conclusion Acidification has a long history as posing adverse impacts on various ecosystems and human health. The main sources of pollution are SO2 and NOX. These pollutants are naturally exist, however recent increases of these pollutants are caused by human-induced factors, such as power generation and transportation. Remedial measures have been taken to abate damaged environment by acid deposition. Preventive measures have been adopted for preventing further damages. In attempts to make steadily progress for both redemption and prevention for solution of acidification for water quality, use of combination of short-term and long-term solution will be recommended. Acid Rain Acid rain is a rain or any other form of precipitation that is unusually acidic, i. e. elevated levels of hydrogen ions (low pH). It can have harmful effects on plants, aquatic animals, and infrastructure through the process of wet deposition. Acid rain is caused by emissions of sulfur dioxide and nitrogen oxides which react with the water molecules in the atmosphere to produce acids. Governments have made efforts since the 1970s to reduce the release of sulfur dioxide into the atmosphere with positive results. Nitrogen oxides can also be produced naturally by lightning strikes and sulfur dioxide is produced by volcanic eruptions. The corrosive effect of polluted, acidic city air on limestone and marble was noted in the 17th century by John Evelyn, who remarked upon the poor condition of the Arundel marbles. Since the Industrial Revolution, emissions of sulfur dioxide and nitrogen oxides to the atmosphere have increased. In 1852, Robert Angus Smith was the first to show the relationship between acid rain and atmospheric pollution in Manchester, England. Though acidic rain was discovered in 1852, it was not until the late 1960s that scientists began widely observing and studying the phenomenon. [6] The term â€Å"acid rain† was coined in 1872 by Robert Angus Smith. 7] Canadian Harold Harvey was among the first to research a â€Å"dead† lake. Public awareness of acid rain in the U. S increased in the 1970s after The New York Times promulgated reports from the Hubbard Brook Experimental Forest in New Hampshire of the myriad deleterious environmental effects demonstrated to result from it. Occasional pH readings in rain and fog water of well below 2. 4 have been reported in industrialized areas. Industrial acid rain is a substantial problem in China and Russia and areas down-wind from them. These areas all burn sulfur-containing coal to generate heat and electricity. The problem of acid rain not only has increased with population and industrial growth, but has become more widespread. The use of tall smokestacks to reduce local pollution has contributed to the spread of acid rain by releasing gases into regional atmospheric circulation. [13][14] Often deposition occurs a considerable distance downwind of the emissions, with mountainous regions tending to receive the greatest deposition (simply because of their higher rainfall). An example of this effect is the low pH of rain (compared to the local emissions) which falls in Scandinavia. Acid rain The French chemist Ducros first used the term ‘pluie acide' in 1845. The phraqse ‘acid rain' ,was brought in 1872 by Robert Angus Smith (Wellburn, 1994). Back in fifties, there were observations of lakes in Scandinavia losing their fish populations. Anglers and naturalists noticed that fish stocks in many lakes of southern Scandinavia were diminishing. Freshwater acidification had rapidly worsened over a few decades. Although acid rain and the acidification are a not new problem that has received considerable attention for many years, it was not until 1960s that scientists were able to link these effects to any specific cause. Later it was found to be atmospheric pollution. Acidification is not a regional phenomenon. In Scotland, studies show that the acidification began around the middle of the last centuries and the process has accelerated in the last three decades. In southern Norway, It has reported that 87 lakes had a pH below 5.5 (Mason, 1996). Damaged forests were becoming widespread in West Germany. As these examples show, acidification is an international problem. Pollutants may be carried with winds over distances, from points hundreds or thousands of miles away. Some countries are net importers of pollution, and others are exporters. The effects of acidification are varies, not only pollution of lakes and forests as previously mentioned, but also effects on fauna and flora, soil, groundwater and direct or indirect harm on human health, and all things are influenced by water quality through hydrological pathway (Thunberg, 1993). The aim of this report is to discuss causes and effects of acidification that has been concerned until now, and present possible short-term and long-term soluti on to acid deposition effects on water quality 1. Acidification and its causes Airborne pollution can influence the environment both directly and indirectly. Primary pollutant is Sulphur dioxide and nitrogen oxides. When these are present in high concentrations, they can cause damage on environment and human's health. These direct effects are often peak in the vicinity of the emission sources. Industrial society discharges suphur dioxide and nitrogen that form sulphuric acid and nitric acid, which may be carried with the winds over long distances before descending in rain or snow. Indirect effects often occur as acidified soil and water far away from the sources of emission (Thunberg, 1993). There are gas-phase reactions, which produce acidity in the atomosphere. Sulphur dioxide and nitrogen oxides form suophuric and nitric acids on coming into contact with water. When these acids reach the ground in rain and snow, it is called ‘wet deposition'. However, acid oxides may also be deposited directy as gases, or cles, which is called ‘dry deposition'. The rates of dry deposition velocity may depend on the nature of the land surfaces. Rates of wet deposition depend on the precipitation rate, the washout ratio of dissolved pollutant per unit mass of cloud water or rain divided by the concentration of the same pollutant per unit mass of air (Wellburn, 1994. A low pH value means a high level of acidification. Water in neutral condition has a pH of 7 (Thunberg, 1993). Sulphur and Nitrogen Cycles are presented below (Figure 1 and 2). Figure 1. Sulphur Cycle Source: ICU (2003) Figure 2. Nitrogen Cycle Source: ICU (2003) 1.1 Sulphur Sulphur compounds are responsible for about two-thirds of the acidification of rain. Sulphur in gaseous form, sulphur dioxide (SO2), is mainly formed in the combustion of oil and coal. The rapid increase in emission of pollutants came after the war followed by consumption of fuel and oil. It was reported that approximately 20 million tons of sulphur are now emitted every year in Europe. There is also a great deal of airborne pollution in North America, where about 12 million tons of sulphur is released every year. Sulphur can be formed by naturally by eruption of vulcanoes, from seas and oceans and certain processes in the soil. However, 90 per cent of the emissions of sulphur to the atmosphere are derived from industrialised parts of Europe and North America. This is ten times the level that can be considered natural (Thunberg, 1993). 1.2 Nitrogen Nitrogen oxides (NOX) are grouped term of nitrogen monoxide (NO) and nitrogen dioxide (NO2). Nitrogen oxides are formed in all types of combustion, most of the NOX are formed by the reaction of nitrogen gas in the combustion air with oxygen. When the mixture of nitrogen gas and oxygen is heated, they interrelate to form NOX. The higher the combustion temperature, the more NOX will be formed. The largest source of NOX emission is road traffic. These emissions are reported to have doubled during the 1960s, approximately 22 million tons of NO2 are released every year in Europe. Certain types of fertilizer are another source of nitrogen pollution. Nitrate leaching intensified the acidification of the soil, which release unwanted substances such as aluminium (Thunberg, 1993). 2. The environmental effects of acidification 2.1 water acidification and aquatic biota Acidification was first noticed in the lakes. The initial victims of acidification are nutrient-deficient lakes in areas where the soil has a poor buffering ability (Thunberg, 1993). It is reported that many lakes in the Rocky Mountain have little alkalinity to buffer increase in acid deposition, however loss of alkalinity has been observed caused by high concentration of acid deposition due to the emission in the Rocky Mountain region (Turk et al, 1989). Figure 3. Acidified lake: A deep blue colour of a lake is a sign of acidification. Source: ARIC (2000) In severely acidified lake, the fish will have vanished entirely, bog moss will have spread out over the lake floor, and only few plant and animal species will remain. The first victims of acidification are crayfish, snails and mussels, certain types of zoo- and phytoplankton, and some species of mayfly. Usually, certain types of bog moss and insects those are resistant to acidification remains. This is not only low pH value that takes a heavy toll of fauna and flora. In acid lakes there are increased concentrations of aluminium in ion form, which is highly toxic to many organisms. The loss of fauna / flora is due to the combination of a lowered pH and aluminium poisoning. The level of other heavy metals also rises such as cadmium, zinc, and lead. Those heavy metals including aluminium flow into lakes from the acidified soils of the surroundings. The relationship of prey and predators will also change, for instance certain insects on which they usually prey begin to thrive when their predators are disappeared (Thunberg, 1993). 2.2 Soil/water interactions Acidification process takes place naturally in the soil. The plant releases hydrogen ions as it uptake nutrients. Though the growth itself is acidifying, there is no net acidification where growth and decay are about equal. However, the cycle is broken by harvesting, the acidifying process will take over. Soil acidification may have biological effects in the respects through lowering of the pH value, an increase in the levels of aluminium and other toxic compounds and a loss of plant nutrients due to increased leaching, consequently may lower drainage water pH (Thunberg, 1993). Moreover, Long-term increase in nitrogen supply may be responsible for alterations in root and shoot growth of plants(Carrol et al, 2003). Figure 5. Soil pH range source ANRA (2003) 2.3 Effects of forestry practices Forestry practices can cause the soil and water to become acidified in several ways. Forest growth change drainage water pathways to stream, and increase stream water acidity. Extensive clear cutting can also accelerate the acidification of surface water. Applying acidifying fertilizer also helps to acidify soil and water (Thunberg, 1993). Twelve years studies of acidification-induced chemical changes in soils of Norway spruce and Scot pine in southern Sweden reveals that pH in mineral soil decreased on average 0.17 units between 1988 and 1999. It is said that these changes in forest soil are mainly due to the extensive deposition of acidifying substances (sulphur and nitrogen compounds) during the latter part of the 20th century (Jà ¯Ã‚ ¿Ã‚ ½nsson et al, 2003). In addition, atmospheric pollution directly damages forest itself. Since the early 1970s, West Germany has experienced a rapid and widespread decline in the health of its forest trees; especially sensitive species were affec ted by exposure to low levels of pollutants (Ling et al, 1987). 2.5 Groundwater quality Most of the precipitation sinks to some extent into the ground. The more permeable the soil, the more water dribbles down. Normally acid rain will become less acid as it penetrates through the ground. However, where the soil becomes acidified and has less ability to neutralize, the effect will be decrease until it finally ceases. It is unlikely that acid groundwater will be harmful to human health, however toxic heavy metals, such as aluminium and cadmium may appear at elevated level where highly acidic. These metals are harmful for human health (Thunberg, 1993). 3. Solutions Solutions to the problems of acidification fall into two groups, which are cure and prevention. Remedial measures can be applied where the problems actually arise (i.e. soils and surface waters). Preventive measures can be applied at source (i.e. at point of emission of the sulphur and nitrogen oxides). The latter are expensive and the least acceptable to industry, however they are in fact more effective, more sustainable, and more immediately required (Park, 1987). Causal treatment by reducing aciditying emissions is the primary goal in a long-term as preventive measures, however outcomes from this approach are still uncertain and recovery may be slow. Indicative treatment, involving the addition of neutralizing agent such as powdered limestone to affected environment is the only realistic remedy in the short-term, and has become a widespread practice in Europe (Thunberg, 1993). 3.1 Short-term solutions Remedial action should be taken after the problems happen. This requires not simply the elimination of symptoms of damage (i.e. restocking fish in acidified lakes, planting new trees); it also involves restoration of natural chemical balances to ensure that damage does not reappear. Some materials in nature have ability to buffer, or neutralize, or offset acid input. Lime and limestone are the most accepted of a range of chemicals that can be used to buffer acidic materials. Lime has been added normally by spraying from helicopter to catchments, soils and forests to alleviate damage and improve conditions for environment (Park, 1987). With regard to the lakes and streams, this raises pH value of the water and decrease in the levels of heavy metals. After the liming many species quickly return to their former habitat (Thunberg, 1993). This approach has been most widely investigated in Sweden (Park, 1987). This measure had been made in UK as well. Stream chemistry and biological effect was monitored for 10 years after the catchments of three acidified Welsh streams at Llyn Brianne were limed in 1987/88. This monitoring reveals that chemistry in treated streams changed significantly as mean annual pH increased from 5-5.1 before liming to 6.1-6.2; mean annual aluminium concentrations decreased from 0.15-0.18 to 0.05-0.11 mg L-1, and calcium concentrations increased from 0.8-2.0 to 2.4-4.5 mg L-1. The abundance of Acid-sensive taxa in limed streams increased after treatment. Liming has also been used as a means of restoring acidified soils. This improves the productivity of croplands and forests. However, liming can cause negative impacts on stream, such as fine CaCO3 deposited on the stream banthos. In addition, liming is an expensive ‘cure' measure. Sweden spent approximately $10 million from 1980-1983 for liming. Moreover, it is not practical for many lakes and rives, for some streams it is no help at all. There is uncertainty in relation to the effect of liming in a long run. Many studies have undertaken for the effects of post liming over short timescales, yet little has known about the long-term effects. At least 10 years monitoring is recommended (Bradley et al, 2002). Liming is a interim measures that provide biological defence, however it does not attack the root caused of the problems. It has been said that ‘a sort of artificial respiration for dead lakes and streams'. Therefore, real effective measures are long-term prevention deliberate through a sustained policy, rather than cure. 3.2 Long-term solutions The only way to solve the problem of acidification in the long run is to reduce emissions of pollutants. The central point of the political debate over acid rain is the need to reduce rainfall acidity by controlling emission of SO2 and NOX at source, mainly from power stations and vehicles: Reducing emissions of SO2 from power stations by: > Burn less fossil fuel > Switch to low-sulphur fuel > Fuel desulphurisation > Sulphur reduction at combustion > Flue gas desulphurisation > Disperse flue gases Reducing emission of NOx from power stations by: > Reduce NOx emissions during burning > Reduce NOx levels after burning Reducing emissions of NOx from vehicles by: > Modify engines or exhausts to reduce emissions > Change to different type of engine > Transport planning It is said that technology of controlling and reducing such emissions already exist. Some methods should be applied separately or in combination to be able to bring reduction to agreed levels within agreed time-scales. However, this problem is not only to do with a technical one. Political goodwill is essential as this measures involves high cost. All the cost should be offset by positive side-effects such as the creation of new jobs and generation of useful by-products (i.e. commercial sulphuric acid), the values of conserving fish, forest and crops, and benefits in improved human health (Park, 1987). In recent decades, there have been national and international efforts to achieve reduction in emissions of sulphur and nitrogen compounds to the atmosphere (Ferrier et at, 2001). As previously mentioned, emissions of sulphur and Nitrogen are carried by air and deposited as gases and aerosols and dissolved in rainwater, in areas far from their sources. The quality of air is very much influenced by emissions in others, so it will benefit little for any country alone to reduce emissions. This is called transboundary Import-Export Budgets. Data for 1998 is presented in Appendix A Without international cooperation, there can be no real solution (Thunberg, 1993). The details of these treaties and protocols are presented in Appendix C 4. Improvement Recent data shows that both emissions seem steadily declined particularly after these treaties and protocols noted above have adopted (See appendix B). However, compared to reduction of SO2 emission, NOX emission need to be reduced further, especially U.S, whose emission has not been much reduced. Conclusion Acidification has a long history as posing adverse impacts on various ecosystems and human health. The main sources of pollution are SO2 and NOX. These pollutants are naturally exist, however recent increases of these pollutants are caused by human-induced factors, such as power generation and transportation. Remedial measures have been taken to abate damaged environment by acid deposition. Preventive measures have been adopted for preventing further damages. In attempts to make steadily progress for both redemption and prevention for solution of acidification for water quality, use of combination of short-term and long-term solution will be recommended. Acid rain The French chemist Ducros first used the term ‘pluie acide' in 1845. The phraqse ‘acid rain' ,was brought in 1872 by Robert Angus Smith (Wellburn, 1994). Back in fifties, there were observations of lakes in Scandinavia losing their fish populations. Anglers and naturalists noticed that fish stocks in many lakes of southern Scandinavia were diminishing. Freshwater acidification had rapidly worsened over a few decades. Although acid rain and the acidification are a not new problem that has received considerable attention for many years, it was not until 1960s that scientists were able to link these effects to any specific cause. Later it was found to be atmospheric pollution. Acidification is not a regional phenomenon. In Scotland, studies show that the acidification began around the middle of the last centuries and the process has accelerated in the last three decades. In southern Norway, It has reported that 87 lakes had a pH below 5.5 (Mason, 1996). Damaged forests were becoming widespread in West Germany. As these examples show, acidification is an international problem. Pollutants may be carried with winds over distances, from points hundreds or thousands of miles away. Some countries are net importers of pollution, and others are exporters. The effects of acidification are varies, not only pollution of lakes and forests as previously mentioned, but also effects on fauna and flora, soil, groundwater and direct or indirect harm on human health, and all things are influenced by water quality through hydrological pathway (Thunberg, 1993). The aim of this report is to discuss causes and effects of acidification that has been concerned until now, and present possible short-term and long-term soluti on to acid deposition effects on water quality 1. Acidification and its causes Airborne pollution can influence the environment both directly and indirectly. Primary pollutant is Sulphur dioxide and nitrogen oxides. When these are present in high concentrations, they can cause damage on environment and human's health. These direct effects are often peak in the vicinity of the emission sources. Industrial society discharges suphur dioxide and nitrogen that form sulphuric acid and nitric acid, which may be carried with the winds over long distances before descending in rain or snow. Indirect effects often occur as acidified soil and water far away from the sources of emission (Thunberg, 1993). There are gas-phase reactions, which produce acidity in the atomosphere. Sulphur dioxide and nitrogen oxides form suophuric and nitric acids on coming into contact with water. When these acids reach the ground in rain and snow, it is called ‘wet deposition'. However, acid oxides may also be deposited directy as gases, or cles, which is called ‘dry deposition'. The rates of dry deposition velocity may depend on the nature of the land surfaces. Rates of wet deposition depend on the precipitation rate, the washout ratio of dissolved pollutant per unit mass of cloud water or rain divided by the concentration of the same pollutant per unit mass of air (Wellburn, 1994. A low pH value means a high level of acidification. Water in neutral condition has a pH of 7 (Thunberg, 1993). Sulphur and Nitrogen Cycles are presented below (Figure 1 and 2). Figure 1. Sulphur Cycle Source: ICU (2003) Figure 2. Nitrogen Cycle Source: ICU (2003) 1.1 Sulphur Sulphur compounds are responsible for about two-thirds of the acidification of rain. Sulphur in gaseous form, sulphur dioxide (SO2), is mainly formed in the combustion of oil and coal. The rapid increase in emission of pollutants came after the war followed by consumption of fuel and oil. It was reported that approximately 20 million tons of sulphur are now emitted every year in Europe. There is also a great deal of airborne pollution in North America, where about 12 million tons of sulphur is released every year. Sulphur can be formed by naturally by eruption of vulcanoes, from seas and oceans and certain processes in the soil. However, 90 per cent of the emissions of sulphur to the atmosphere are derived from industrialised parts of Europe and North America. This is ten times the level that can be considered natural (Thunberg, 1993). 1.2 Nitrogen Nitrogen oxides (NOX) are grouped term of nitrogen monoxide (NO) and nitrogen dioxide (NO2). Nitrogen oxides are formed in all types of combustion, most of the NOX are formed by the reaction of nitrogen gas in the combustion air with oxygen. When the mixture of nitrogen gas and oxygen is heated, they interrelate to form NOX. The higher the combustion temperature, the more NOX will be formed. The largest source of NOX emission is road traffic. These emissions are reported to have doubled during the 1960s, approximately 22 million tons of NO2 are released every year in Europe. Certain types of fertilizer are another source of nitrogen pollution. Nitrate leaching intensified the acidification of the soil, which release unwanted substances such as aluminium (Thunberg, 1993). 2. The environmental effects of acidification 2.1 water acidification and aquatic biota Acidification was first noticed in the lakes. The initial victims of acidification are nutrient-deficient lakes in areas where the soil has a poor buffering ability (Thunberg, 1993). It is reported that many lakes in the Rocky Mountain have little alkalinity to buffer increase in acid deposition, however loss of alkalinity has been observed caused by high concentration of acid deposition due to the emission in the Rocky Mountain region (Turk et al, 1989). Figure 3. Acidified lake: A deep blue colour of a lake is a sign of acidification. Source: ARIC (2000) In severely acidified lake, the fish will have vanished entirely, bog moss will have spread out over the lake floor, and only few plant and animal species will remain. The first victims of acidification are crayfish, snails and mussels, certain types of zoo- and phytoplankton, and some species of mayfly. Usually, certain types of bog moss and insects those are resistant to acidification remains. This is not only low pH value that takes a heavy toll of fauna and flora. In acid lakes there are increased concentrations of aluminium in ion form, which is highly toxic to many organisms. The loss of fauna / flora is due to the combination of a lowered pH and aluminium poisoning. The level of other heavy metals also rises such as cadmium, zinc, and lead. Those heavy metals including aluminium flow into lakes from the acidified soils of the surroundings. The relationship of prey and predators will also change, for instance certain insects on which they usually prey begin to thrive when their predators are disappeared (Thunberg, 1993). 2.2 Soil/water interactions Acidification process takes place naturally in the soil. The plant releases hydrogen ions as it uptake nutrients. Though the growth itself is acidifying, there is no net acidification where growth and decay are about equal. However, the cycle is broken by harvesting, the acidifying process will take over. Soil acidification may have biological effects in the respects through lowering of the pH value, an increase in the levels of aluminium and other toxic compounds and a loss of plant nutrients due to increased leaching, consequently may lower drainage water pH (Thunberg, 1993). Moreover, Long-term increase in nitrogen supply may be responsible for alterations in root and shoot growth of plants(Carrol et al, 2003). Figure 5. Soil pH range source ANRA (2003) 2.3 Effects of forestry practices Forestry practices can cause the soil and water to become acidified in several ways. Forest growth change drainage water pathways to stream, and increase stream water acidity. Extensive clear cutting can also accelerate the acidification of surface water. Applying acidifying fertilizer also helps to acidify soil and water (Thunberg, 1993). Twelve years studies of acidification-induced chemical changes in soils of Norway spruce and Scot pine in southern Sweden reveals that pH in mineral soil decreased on average 0.17 units between 1988 and 1999. It is said that these changes in forest soil are mainly due to the extensive deposition of acidifying substances (sulphur and nitrogen compounds) during the latter part of the 20th century (Jà ¯Ã‚ ¿Ã‚ ½nsson et al, 2003). In addition, atmospheric pollution directly damages forest itself. Since the early 1970s, West Germany has experienced a rapid and widespread decline in the health of its forest trees; especially sensitive species were affec ted by exposure to low levels of pollutants (Ling et al, 1987). 2.5 Groundwater quality Most of the precipitation sinks to some extent into the ground. The more permeable the soil, the more water dribbles down. Normally acid rain will become less acid as it penetrates through the ground. However, where the soil becomes acidified and has less ability to neutralize, the effect will be decrease until it finally ceases. It is unlikely that acid groundwater will be harmful to human health, however toxic heavy metals, such as aluminium and cadmium may appear at elevated level where highly acidic. These metals are harmful for human health (Thunberg, 1993). 3. Solutions Solutions to the problems of acidification fall into two groups, which are cure and prevention. Remedial measures can be applied where the problems actually arise (i.e. soils and surface waters). Preventive measures can be applied at source (i.e. at point of emission of the sulphur and nitrogen oxides). The latter are expensive and the least acceptable to industry, however they are in fact more effective, more sustainable, and more immediately required (Park, 1987). Causal treatment by reducing aciditying emissions is the primary goal in a long-term as preventive measures, however outcomes from this approach are still uncertain and recovery may be slow. Indicative treatment, involving the addition of neutralizing agent such as powdered limestone to affected environment is the only realistic remedy in the short-term, and has become a widespread practice in Europe (Thunberg, 1993). 3.1 Short-term solutions Remedial action should be taken after the problems happen. This requires not simply the elimination of symptoms of damage (i.e. restocking fish in acidified lakes, planting new trees); it also involves restoration of natural chemical balances to ensure that damage does not reappear. Some materials in nature have ability to buffer, or neutralize, or offset acid input. Lime and limestone are the most accepted of a range of chemicals that can be used to buffer acidic materials. Lime has been added normally by spraying from helicopter to catchments, soils and forests to alleviate damage and improve conditions for environment (Park, 1987). With regard to the lakes and streams, this raises pH value of the water and decrease in the levels of heavy metals. After the liming many species quickly return to their former habitat (Thunberg, 1993). This approach has been most widely investigated in Sweden (Park, 1987). This measure had been made in UK as well. Stream chemistry and biological effect was monitored for 10 years after the catchments of three acidified Welsh streams at Llyn Brianne were limed in 1987/88. This monitoring reveals that chemistry in treated streams changed significantly as mean annual pH increased from 5-5.1 before liming to 6.1-6.2; mean annual aluminium concentrations decreased from 0.15-0.18 to 0.05-0.11 mg L-1, and calcium concentrations increased from 0.8-2.0 to 2.4-4.5 mg L-1. The abundance of Acid-sensive taxa in limed streams increased after treatment. Liming has also been used as a means of restoring acidified soils. This improves the productivity of croplands and forests. However, liming can cause negative impacts on stream, such as fine CaCO3 deposited on the stream banthos. In addition, liming is an expensive ‘cure' measure. Sweden spent approximately $10 million from 1980-1983 for liming. Moreover, it is not practical for many lakes and rives, for some streams it is no help at all. There is uncertainty in relation to the effect of liming in a long run. Many studies have undertaken for the effects of post liming over short timescales, yet little has known about the long-term effects. At least 10 years monitoring is recommended (Bradley et al, 2002). Liming is a interim measures that provide biological defence, however it does not attack the root caused of the problems. It has been said that ‘a sort of artificial respiration for dead lakes and streams'. Therefore, real effective measures are long-term prevention deliberate through a sustained policy, rather than cure. 3.2 Long-term solutions The only way to solve the problem of acidification in the long run is to reduce emissions of pollutants. The central point of the political debate over acid rain is the need to reduce rainfall acidity by controlling emission of SO2 and NOX at source, mainly from power stations and vehicles: Reducing emissions of SO2 from power stations by: > Burn less fossil fuel > Switch to low-sulphur fuel > Fuel desulphurisation > Sulphur reduction at combustion > Flue gas desulphurisation > Disperse flue gases Reducing emission of NOx from power stations by: > Reduce NOx emissions during burning > Reduce NOx levels after burning Reducing emissions of NOx from vehicles by: > Modify engines or exhausts to reduce emissions > Change to different type of engine > Transport planning It is said that technology of controlling and reducing such emissions already exist. Some methods should be applied separately or in combination to be able to bring reduction to agreed levels within agreed time-scales. However, this problem is not only to do with a technical one. Political goodwill is essential as this measures involves high cost. All the cost should be offset by positive side-effects such as the creation of new jobs and generation of useful by-products (i.e. commercial sulphuric acid), the values of conserving fish, forest and crops, and benefits in improved human health (Park, 1987). In recent decades, there have been national and international efforts to achieve reduction in emissions of sulphur and nitrogen compounds to the atmosphere (Ferrier et at, 2001). As previously mentioned, emissions of sulphur and Nitrogen are carried by air and deposited as gases and aerosols and dissolved in rainwater, in areas far from their sources. The quality of air is very much influenced by emissions in others, so it will benefit little for any country alone to reduce emissions. This is called transboundary Import-Export Budgets. Data for 1998 is presented in Appendix A Without international cooperation, there can be no real solution (Thunberg, 1993). The details of these treaties and protocols are presented in Appendix C 4. Improvement Recent data shows that both emissions seem steadily declined particularly after these treaties and protocols noted above have adopted (See appendix B). However, compared to reduction of SO2 emission, NOX emission need to be reduced further, especially U.S, whose emission has not been much reduced. Conclusion Acidification has a long history as posing adverse impacts on various ecosystems and human health. The main sources of pollution are SO2 and NOX. These pollutants are naturally exist, however recent increases of these pollutants are caused by human-induced factors, such as power generation and transportation. Remedial measures have been taken to abate damaged environment by acid deposition. Preventive measures have been adopted for preventing further damages. In attempts to make steadily progress for both redemption and prevention for solution of acidification for water quality, use of combination of short-term and long-term solution will be recommended.