Liming lakes and rivers

Acidification of lakes and rivers is one of the most serious environmental problems in Norway. Acid rain is a threat to aquatic biodiversity: it has resulted in the loss or depletion of more than 15 000 fish stocks. Liming is an effective way of reducing the damage.

Acidification of Norway’s lakes and rivers is mainly caused by pollutants from other countries that are transported in the atmosphere and deposited as acid rain. This problem can only be reduced through international agreements to reduce releases of pollutants.

Critical loads for deposition of acid rain are still being exceeded in much of the southern half of Norway. Liming makes lakes and rivers less acidic, improving the water chemistry and providing better conditions for fish and other freshwater organisms. The Norwegian authorities provide substantial funding for liming of many rivers and lakes.

The Norwegian Environment Agency has drawn up an action plan for liming for the period 2011–15.

Damage worsened as pollution rose

Acidification started in Norway with the Industrial Revolution in the 1800s, and continued to worsen until the 1970s. In 1925, it was discovered that fish mortality was caused by acid water, but the links with acid rain were not understood until the 1950s. More and more fish stocks were damaged as the problem spread, leading to losses of aquatic biodiversity generally.

When the situation was at its worst, 30 % of mainland Norway was affected, and one in five species disappeared from the most acidic river systems. More than 15 000 fish stocks were wiped out or depleted: Norway lost 25 of its salmon stocks, and at least 20 others were depleted. The damage was worst in Vest-Agder and Aust-Agder counties in the far south of the country.

Liming improves water quality

Liming programmes started in the mid-1980s, and 21 salmon rivers and 2 500 lakes and streams are now limed regularly. The effects are documented by monitoring water chemistry, fish, benthic animals and aquatic vegetation.

Many years of liming combined with reductions in acid deposition have improved water quality to the extent that ecosystems are recovering. The lower acidity (higher pH) improves conditions directly, and also means that less aluminium – which is highly toxic to many aquatic species – is released from soils. Both salmon stocks and their prey species are recovering, although there is still a considerable potential for further improvement of species diversity.

Since 2000, however, the positive trend has levelled off, and no major improvement is expected after 2010. Acid rain (sulphur and nitrogen deposition) is still a serious threat to freshwater biodiversity in Norway. About 10 % of mainland Norway is now damaged by acidification, with the most serious effects in the southernmost and westernmost parts of the country.

Sensitive to acid rain

Much of the southern half of Norway has thin soil cover on bedrock consisting of acidic rocks such as gneiss and granite. These areas are very sensitive to acid rain. The liming programme is most extensive in the counties that are worst affected – Aust-Agder, Vest-Agder, Rogaland and Hordaland – and will have to be continued until critical loads for acidification of surface water are no longer exceeded.

Critical loads are used to express how much acidification different ecosystems can absorb without damage. In Norway, freshwater ecosystems are particularly sensitive to acidification, and critical loads are therefore low.

Linked to fossil fuels

Acid rain is mainly caused by combustion of fossil fuels. Power plants, industrial processes and transport are the major sources of the emissions that cause acid rain. About 90 % of the sulphur and nitrogen deposited in Norway originates in other countries, especially the UK, Germany and Poland. This means that the amount of acid rain falling on Norway is to a large extent determined by developments elsewhere in Europe.

Sulphur emissions in Europe have been greatly reduced in the past 20–30 years. In Eastern Europe, this is partly a result of economic problems that have led to the closure of factories and lower energy production. In Western Europe, cuts in emissions have generally been achieved by installing emission abatement technology at industrial plants and by switching to the use of low-sulphur fuels. Motor vehicles and other mobile sources are an important source of nitrogen emissions, and this has made it more difficult to reduce releases of nitrogen. 

International agreements on cuts in emissions

Since 1980, total deposition of sulphur in precipitation in Norway has been reduced by about 75 %, while the corresponding figure for nitrogen is about 35 %. The reductions have largely been brought about by countries taking action to meet their commitments under international agreements.

Several binding protocols have been adopted under the Convention on Long-range Transboundary Air Pollution, including the Gothenburg Protocol, which entered into force in 2005. There are 26 parties to the Protocol, which in its first phase set emission ceilings for 2010 for sulphur, nitrogen oxides (NOx) and other pollutants. In 2012, new national emission reductions were agreed to be achieved in 2020 and beyond.

Acid Deposition In UK

Acid rain is a general name for many phenomena including acid fog, acid sleet, and acid snow. Although we associate the acid threat with rainy days, acid deposition occurs all the time, even on sunny days.

Acid Deposition is the scientific term used to describe "Acid Rain". When atmospheric pollutants such as sulphur dioxide and nitrogen oxides mix with water vapour in the air, they are converted to sulphuric and nitric acids. These acids make the rain acidic, hence the term "acid rain". Rain returns the sulphur and nitrogen acids to Earth, and in high concentrations, can cause damage to natural environments including forests and freshwater lakes. This form of acid deposition is known as wet deposition. A second method of acid deposition is known as dry deposition. Whilst wet deposition involves the precipitation of acids, dry deposition occurs when the acids are first transformed chemically into gases and salts, before falling under the influence of gravity back to Earth. Sulphur dioxide, for example, is deposited as a gas and as a salt.

The gases present in acid deposition are found to occur naturally in the environment. They are given off from a number of sources including volcanic eruptions and the rotting of vegetation. They become a problem when humans produce the gases in large amounts, and at high concentrations by the burning of fossil fuels.

The distances that pollutant gases travel means that acid deposition is an international or transboundary problem. This means that acid pollutants are not necessarily deposited in the same country where they were produced.

Acidic Emissions In Uk

Rain water is naturally acidic as a result of carbon dioxide dissolved in water and from volcanic emissions of sulphur. However, it is the chemical conversion of sulphur and nitrogen emissions from power stations, factories, vehicles and homes, where fossil fuels are burnt, that we call acid rain. These waste gases are carried by the wind, sometimes over long distances, and can in time be converted into sulphuric and nitric acids.

Natural sources of sulphur dioxide (SO2) include releases from volcanoes, oceans, biological decay and forest fires. Actual amounts released from natural sources in the world are difficult to quantify; in 1983 the United Nations Environment Programme estimated a figure of between 80 million and 288 million tonnes of sulphur oxides per year. Man-made sulphur dioxide emissions result from combustion or burning of fossil fuels, due to varying amounts of sulphur being present in these fuels. Worldwide emissions of SO2 are thought to be around 69 million tonnes per year.

Levels of sulphur dioxide from combustion sources in the UK have declined in recent decades. Between 1970 and 1999, UK sulphur dioxide emissions fell by 82% due to recession, restructuring of industry, substitution of fuels (for example natural gas) and air pollution control technology. Power station emissions fell by 73% over the same period, but the percentage of UK emissions from power stations has actually increased to 65% of the 1999 total compared to 45% of the total in 1970.

Natural sources of nitrogen oxides (NOx) include volcanoes, lightening strikes and biological decay. Estimates range from between 20 million and 90 million tonnes per year NOx released from natural sources, compared to around 24 million tonnes from human sources world-wide. Nitrogen oxides are produced when fossil fuels are burned. The major sources of NOx in the UK in 1999 were road transport (44%), power stations (21%) and industry (including iron and steel, and refineries) (12%). Emissions of nitrogen oxides from road transport increased during the 1970s and 1980s before decreasing again during the 1990s. For example, in 1970, emissions of NOx from road transport in the UK were 0.769 million tonnes by in 1990 they had risen to over 1.31 million tonnes NOx. Since then, however, emissions from transport have been declining due to improvements in vehicle technology, such as the use of catalytic converters, and the use of cleaner fuels. In 1999 they were 0.714 million tonnes, lower than in 1970.

The geographical distribution of human acidic emission sources is not even. Nitrogen and sulphur emission sources are heavily concentrated in the Northern Hemisphere, particularly in Europe and North America. As a result, precipitation is generally more acidic in these countries, with an acidity in the range pH 4.1 to pH 5.1. �Normal� or �unpolluted� rainfall has a pH of 5.6.

Acid Rain

Acids form when certain atmospheric gases (primarily carbon dioxide, sulfur dioxide, and nitrogen oxides) come in contact with water in the atmosphere or on the ground and are chemically converted to acidic substances. Oxidants play a major role in several of these acid-forming processes. Carbon dioxide dissolved in rain is converted to a weak acid (carbonic acid). Other gases, primarily oxides of sulfur and nitrogen, are converted to stronq acids (sulfuric and nitric acids).

Although rain is naturally slightly acidic because of carbon dioxide, natural emissions of sulfur and nitrogen oxides, and certain organic acids, human activities can make it much more acidic. Occasional pH readings of well below 2.4 (the acidity of vinegar) have been reported in industrialized areas.

The principal natural phenomena that contribute acid-producing gases to the atmosphere are emissions from volcanoes and from biological processes that occur on the land, in wetlands, and in the oceans. The effects of acidic deposits have been detected in glacial ice thousands of years old in remote parts of the globe. Principal human sources are industrial and power-generating plants and transportation vehicles. The gases may be carried hundreds of miles in the atmosphere before they are converted to acids and deposited.

Since the industrial revolution, emissions of sulfur and nitrogen oxides to the atmosphere have increased. Industrial and energy-generating facilities that burn fossil fuels, primarily coal, are the principal sources of increased sulfur oxides. These sources, plus the transportation sector, are the major originators of increased nitrogen oxides.

The problem of acid rain not only has increased with population and industrial growth, it 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. The same remote glaciers that provide evidence of natural variability in acidic deposition show, in their more recently formed layers, the increased deposition caused by human activity during the past half century.

Gardens: The surprising Benefits of Acid rain

Sulphur is a key plant nutrient vital to healthy growth, but UK soils are naturally deficient in this essential mineral. Back in the 1980s this was of little concern to growers as these levels were continually topped up by “atmospheric deposition”, ie acid rain.

Fast forward to 2016 and this is increasingly worthy of attention. One small survey conducted over 2014 and 2015, for example, found that only 13% of the crops sampled showed sulphur levels in the “normal” range, with the rest registering as low or slightly low. This is a concern as inadequate sulphur levels have been shown to slash farm yields of some (but admittedly not all) crops by as much as 50%. Surprising as it may seem, even acid rain clouds can have a silver lining.

As many plants also use sulphur pulled up from the soil to generate defence compounds to help ward off pests and diseases, this deficiency can also result in weak, vulnerable crops that require higher pesticide applications. These defence compounds also happen to be the exact same chemicals that give vegetables, like onions, garlic, broccoli and sprouts, their characteristic flavour and associated health benefits. Heard about the antioxidants in broccoli and garlic? It’s the sulphur chemicals, derived from the soil, that are doing the work.

While this effect is likely to be greater in agricultural soils, where crops are constantly taking sulphur from the soil only to be harvested and removed from the site, this can be an issue even in garden soils. Take lawns for example: years of continual mowing and disposal of the grass clippings essentially mimics that of agriculture – acting like a pump on a conveyor belt to suck up the sulphur.

If you suspect your soil is sulphur-deficient, there is a simple solution that offers all of the benefits without the damaging acidity: Epsom salts. This naturally occurring mineral combines both sulphur and another essential plant nutrient, magnesium, in a double whammy and can be bought for minimal cost at any garden centre. Simply sprinkle over the ground according to package directions for higher yields of tastier and more nutritious crops.

Causes and Effects of Acidic Rain Formation

Pictorial aspect of acidic rain formation

The term acidic rain was first used by Robert Angus in 1872. Literally it means the presence of excessive acids in rain water or the fall of acids mixed with rain and snow. Nitrogen oxides and sulphur dioxide which are acidic gases dissolve in in the rain water in the atmosphere and make it acidic. Acidic rain in fact is a cocktail of mainly H2SO4 (Sulfuric acid) and HNO3 (Nitric acid) where the ratio of these two may vary depending on the relative quantities of oxides of sulphur and nitrogen emitted. H2SO4 is the major contributor (60-70 percent) to acid precipitation. HNO3 ranks second (with 30-40 percent) and HCL third.

Although the oxides sulfur and nitrogen have been recognized as the main components responsible for acid rain, their relative contributions to acid rain is still not very clear because of the highly complex nature of their transport and complexity involved in their removal from rain water. Once these oxides have fallen, along with rain water, it is difficult to remove them from the environment. These oxides may travel long distances in the atmosphere and during this journey, they may undergo several physical and chemical transformations to products which may also fall with rain. Hence, acid rain which is mainly a man made is a global ecological challenge. Normal rain water is always slight acidic because of the fact that CO2 present in the atmosphere gets dissolved in it, forming carbonic acid (H2CO3). Because of the presences of SO2 and NO2 gases as pollutants in the atmosphere, the pH (a measure of how acidic/basic water is) of the rain water is further lowered, often to as low as 2.4 and this type of precipitation of lower pH is called acidic rain.

Formation of Acidic rain

Acid rain is the one phase of acid deposition which can either be wet or dry. It is the form of snow, dew, fog, frost and mist represent the wet form of deposition while dust particles containing sulphates and nitrates, settled on earth, and constitute dry deposition. However, the wet rain is much more common. Wet acid rain every source of energy that we use be it coal, fuel wood or petroleum products have sulphur and nitrogen. These two elements, when burnt in atmospheric oxygen, they become converted into their respective oxides (SO2 and NO2) which are highly soluble in water. By anthropogenic and natural sources, oxides of sulphur and nitrogen enter the atmosphere. In case of nitrogen, following reaction, following involved under humid condition of air N2O5 invariably with vapours to form droplet of HNO3. Some HNO2 are also formed. HNO3 and HNO2 are then dropped to the earth's surface. However, HNO3 can be removed as a particulate nitrates after reaction with bases such as NH3. SO3 in humid atmosphere forms droplets of H2SO4. This HNO3 and H2SO4 formed combined with HCL (emitted from natural and man made sources) to generate precipitation which is commonly referred to as acid rain.

What aggravate acidic rains?

Extreme wind can aggravate acidic rain. The oxides of sulphur and nitrogen are swept up into the atmosphere and travel thousands of kilometers. The longer they stay in the air, the more likely they are to be oxidized into acids. For instance, a given molecules of SO2 may remain in the atmosphere up to 40 hours. While a sulphate particles may remain for three weeks. They have enough long life periods and so these molecules may be transported several kilometer from their point of release and aggravate the existence of acidic rain.

Effects of Acidic rain

Acidic rain exerts both direct and indirect effect on both organisms and materials it comes into contact with. The direct effects of rain are determined by concentration of pollutants in the air. They are mainly of local nature with a geographical extent of few kms. They decline rapidly with distance from the emission sources. They affect organisms and material and cause more harm at a distance and some thousands of kms. The dry deposition has several direct effects on environment. It attacks building materials, principally, limestone, marble, steel, nickel and other metals causing loss of millions of dollars spent in making structures like statues and buildings. When deposited in gases, it causes direct damage to plants and trees, the visible injury being gradual yellowing of leaf tissues (chlorosis).

The wet deposition has direct as well as indirect effects. It increases the acidity of lakes and rivers which is made worse inflow of acids and metals from nearby soils. Wet deposition also affects aquatic as well as territorial ecosystems. Vast tracts of forests and lakes in Europe and North America are being destroyed by acidic rain. Wet deposition can transport metals such as Al, Cd, Hg and Cr into soil water, ground water, lakes and streams, depleting the stocks of nutrients in the soil, there by causing harm to various ecosystems. Acidity kills fish, algae, bacteria and aquatic system gets collapsed into the sterility leaving a crystal clear but ultimately a dead lock. Accordingly, a number of acidic precipitation victims were identified by scholars like aquatic biota, lake ecosystem, buildings, human beings.

Acid rain effects on Aquatic Biota

Reduce fish population accompanied by decreasing the variety of species in food chain. There are 15,000 lakes with no living fish population in Sweden and 100 such lakes in the Adirondack region of USA, because of increased acidity of lakes. It create a big exposure to be unfavourable pH levels which was not appropriate for fishes reproductive process, many algae and bacteria will be killed due to acidity, disrupting the whole ecological balance, destroy tree (in west Germany 10 percent of forests perished and 18 millions acres of forests are severely affected), and actual nutrients like calcium, potassium, iron and magnesium have leched a way from soil by acids. It also destroy crops and forest reducing agricultural productivity, retarded the growth of crops like pea, beans, radish, potato, spinash, broccoli, carrots etc. Similarly, in Japan 5000sq kms cedar trees were affected by high acidic deposition.

Acidic rain effects on the ecosystem of lakes

It causes a number of complication in ponds, rivers and lakes where it accumulates as acidic snow. In summer time, rapid snow melting gives a jolt of acid water to lakes that cause the death of a number of Young fishes, algae and insects including discharging food chain. Black flies, mosquitoes, deer flies and other aquatic worms occur abundantly where fishes are eliminated. So, they appear to thrive in acid condition. Dragon fly larvae and water boatmen also flourished in acidified lakes. Moreover, the activity of bacteria and other microscopic animals is reduced in acidic water. So the dead materials and other accumulated substance lying on the bottom of lakes are rapidly decomposed. Thus essential nutrients as nitrogen and phosphorus stay locked up in plant and animal remains. Biomass production is reduced and fish population declines. Aquatic plants like broad leaved trees and weeds do not grow in acidic water.

Acid rain effects on buildings:

Acid rain causes extensive damage on building and structural materials of marble, limestone and slate. Limestone could be attacked rapidly and attacks of marble termed as stone leprosy. In Greece and Italy, invaluable stone have been partially dissolved by acid rain. Further, as a result, ever year, 1450 millions of dollars are lost around the world. For instance Taj Mahal in Arga and British Parliaments Building have also suffered damage of H2SO4. Due to acidity, levels of heavy metals like Al, Mn, Pb, Cd, Cr, and Cu in water increased beyond the safe limits which indirectly affects the buildings. Traces of radio active elements present in radioactive rain severely damage buildings.

Effects of Acid rain on human beings

Acidic rain has been found to be very dangerous to the living organisms as it can destroy life. Acidity can play havoc with nervous system, respiratory system and digestive system by making the person vulnerable to neurological diseases. This happens because these acids produce highly toxic compounds which contaminate the portable water and enter man's body. It also contain air pollutants contribute to a variety of safety hazards, associated with reduced visibility due to smog. Here I tried to familiarize you some core points on how acidic rain is formed, aggravated and also affects the world and living things.

Eventually, as a journalist I would like to applaud Japan's government measure to protect acidic rain effects. [Because] currently, acidic rain measuring kit are available. As to my source, when a chemical is placed in small plastic container and acid rain falls on it, the colour changes and hence the acidity content of the rain can be read. As it had been in Northern Europe and Northern America, it has become significantly noticeable in Japan. Similarly, Japan's Environment Agency has established a national monitoring network and records from 1994 show that pH values in rain fall in 28 place averaged 4.8 and acidic rain fall reported in both urban and rural areas ranging between pH 4.5 to 5.8 .

Therefore, I do have one question for all of us. Are we strong enough to protect such kind of acidic rain effects? What have we been doing to protect our renewable and non-renewable environmental resources? Specially, what our stakeholders, professionals, expertise, researchers, authoritative bodies as well as national and international private sector actors have been doing in their respective roles to withstand the effects of acidic rain? Have the aforementioned effects and signs of acidic rain been observed in your country yet?

Actually, a number of horrible events have been occurring around the world because of acidic rain. For instance, drought, flood starvation and the likes are the direct and indirect results or effects of acidic rain fall. Therefore, we have to be united and get hand to hand so as to protect this as well as the next generation from negative effects of acidic rain.

Acid Rain Facts: The Effects of Chemicals on the Environment and People

Generally speaking, acid rain is any type of precipitation – rain, snow, fog – that contains a high level of nitric or sulfuric acids. Some of this can be caused by natural phenomenon such as volcanic eruptions and even gases emitted by large amounts of rotting vegetation. However, most acid rain comes from human activities, according to National Geographic.

The primary cause is the burning of fossil fuels. This process releases sulfur dioxide and nitrogen oxides into the atmosphere. When these chemical interact with water and oxygen, the reaction forms a solution of sulfuric and nitric acids that falls back to Earth.

These chemicals then move over the planet’s surface along with rain water, sometimes flowing into water systems and also seeping into the soil.

And while the term acid rain is best known, about half of these chemicals come back to Earth as “dry deposition” via dust or smoke, according to the Environmental Protection Agency (EPA). In this form, the chemicals stick to places such as buildings, cars and homes, and eventually get washed off by falling rain, which turns it more acidic.

The Effects of Acid Rain

The most damaging effect of acid rain is typically the contamination of bodies of water – lakes, rivers, streams and wetland areas, according to National Geographic. Acidic waters absorb the aluminum that runs into waterways from the soil, turning the water toxic for many aquatic animals, including crayfish, clams and fish.

This then affects the food chain – non-aquatic animals, such as certain species of birds, are affected by the lack of food in the waterways. In extreme cases, acid rain can lead to “dead lakes,” where most living orgasms no longer thrive.

Vegetation also can be harmed, with acid rain suffusing the soil with aluminum, making it more difficult for plants to absorb needed nutrients.

Effects on Human Health

There are other, perhaps lesser known, affects, according to the EPA.

For example, reports through the years have shown examples of acid rain corroding paint on automobiles, leaving patterns that are irregularly shaped and permanent. It’s easier to see on darker cars or under fluorescent lamps.

Humans are not harmed directly by acid rain, but the indirect damage can be substantial. The pollutants within acid rain can interact with atmospheric gases to create small flakes of particulate that can be inhaled deep into the lungs.

Many studies over the years have shown a correlation between these particles and increased likelihood of illnesses and premature death from lung and heart issues, according to the EPA.

How to Reduce Acid Rain

Stated simply: the fewer chemicals ejected into the air through the burning of fossil fuels, the less chance of acid rain or dry deposition.

Since the burning of fossil fuels continues, the EPA has several suggestions. They include regular cleaning of smokestacks used in operations that burn coal, natural gas and oil, which involves the installation of scrubbers in smokestacks.

Another method is the ongoing effort by both private industry and many governments to find viable alternative energy sources – wind, solar, geothermal and hydro, for example.

The EPA also notes that there are ongoing projects to restore areas damaged by acid rain.

Individuals can also help by using the same steps that are recommended for using less energy in your home – less energy consumed, fewer fossil fuels burned. Example include turning off lights, computers and appliances when they are not being used, installing more energy-efficient appliances, using heating and air conditioning less, insulating your home and carpooling.

While the effects of acid rain are still present, the hope is these steps will help reduce the problem and that efforts to restore areas harmed by acid rain will continue to see success.