Environmental Pollution Effects on Humans, Other Animals & Plants

General Environmental Pollution Effects

Miguel A. Santos notes that a very important aspect of the effect of pollution is its dose (or concentration) required to cause environmental damage. (10)
He defines pollution response as “the change in the effect of a pollutant in response to a change in its concentration”. (11)
In this respect, he identifies 3 different types of response evoked by the environment to different pollution concentrations: (12)

• Linear effect
• Greater-than-linear effect
• Threshold effect

In the linear effect, environmental damage increases linearly with pollution concentrations. In other words, “ the total damage or risk is directly proportional to the accumulated exposure”. (13)
This effect occurs with radioactive substances as well as mercury, lead, cadmium and asbestos.
In the greater-than-linear effect, environmental damage increases with an increase in pollution concentrations but at a decreasing rate. This means that, as pollution concentrations continue to increase the environmental damage will continue to decrease. (14)
This is the case with thermal pollution.
In the threshold effect, pollution produces no effect until a certain threshold in pollution concentrations is achieved. In other words, “so long as a given threshold is not exceeded, the damage from pollution would be completely repaired as quickly as it is produced”. (15)
This effect is found with biodegradable pollutants.
It is also important to mention synergistic effects of pollutants on the environment. While interacting with each other, pollutants can produce greater impacts than when acting individually. (16)
A good example of that is a synergy between asbestos exposure and smoking in causing lung cancer. (17)

There is no doubt that excessive levels of pollution are causing a lot of damage to human & animal health, plants & trees (including tropical rainforests) as well as the wider environment.
All types of environmental pollution – air, water and soil pollution – have an impact on the living environment.
The effects in living organisms may range from mild discomfort to serious diseases such as cancer to physical deformities (for example, extra or missing limbs in frogs).
Experts admit that environmental pollution effects are quite often underestimated and that more research is needed to understand the connections between pollution and its effects on all life forms.

Environmental Pollution Effects on Humans

We know that pollution causes not only physical disabilities but also psychological and behavioral disorders in people.
We are discussing the effects of air pollution and specific air pollutants in more detail in the Air Pollutants article.
The following effects of environmental pollution on humans have been reported:

Air Pollution in Philippines
Photo: Jim D Stitch

Air pollution (18, 19)

• Reduced lung functioning
• Irritation of eyes, nose, mouth and throat
• Asthma attacks
• Respiratory symptoms such as coughing and wheezing
• Increased respiratory disease such as bronchitis
• Reduced energy levels
• Headaches and dizziness
• Disruption of endocrine, reproductive and immune systems
• Neurobehavioral disorders
• Cardiovascular problems
• Cancer
• Premature death

We discuss air pollution effects in more detail here.

Water pollution (20)
Waterborne diseases caused by polluted drinking water:

• Typhoid
• Amoebiasis
• Giardiasis
• Ascariasis
• Hookworm

Waterborne diseases caused by polluted beach water:

• Rashes, ear ache, pink eye
• Respiratory infections
• Hepatitis, encephalitis, gastroenteritis, diarrhoea, vomiting, and stomach aches

Conditions related to water polluted by chemicals (such as pesticides, hydrocarbons, persistent organic pollutants, heavy metals etc):

• Cancer, incl. prostate cancer and non-Hodgkin’s lymphoma
• Hormonal problems that can disrupt reproductive and developmental processes
• Damage to the nervous system
• Liver and kidney damage
• Damage to the DNA
• Exposure to mercury (heavy metal):
  
  • In the womb: may cause neurological problems including slower reflexes, learning deficits, delayed or incomplete mental development, autism and brain damage
  • In adults: Parkinson’s disease, multiple sclerosis, Alzheimer’s disease, heart disease, and even death

Other notes:

• Water pollution may also result from interactions between water and contaminated soil, as well as from deposition of air contaminants (such as acid rain)
• Damage to people may be caused by fish foods coming from polluted water (a well known example is high mercury levels in fish)
• Damage to people may be caused by vegetable crops grown / washed with polluted water (author’s own conclusion)

Soil contamination (21)

• Causes cancers including leukaemia
• Lead in soil is especially hazardous for young children causing developmental damage to the brain
• Mercury can increase the risk of kidney damage; cyclodienes can lead to liver toxicity
• Causes neuromuscular blockage as well as depression of the central nervous system
• Also causes headaches, nausea, fatigue, eye irritation and skin rash

Other notes:

• Contact with contaminated soil may be direct (from using parks, schools etc) or indirect (by inhaling soil contaminants which have vaporized)
• Soil contamination may also result from secondary contamination of water supplies and from deposition of air contaminants (for example, via acid rain)
• Contamination of crops grown in polluted soil brings up problems with food security
• Since it is closely linked to water pollution, many effects of soil contamination appear to be similar to the ones caused by water contamination

An Extreme Oil Pollution Case

Pollution of pristine Ecuador rainforest by Texaco / Chevron oil corporation represents perhaps one of the most outrageous cases of oil pollution ever.
Some levels of pollutants left by the company on its sites of oil exploration have been calculated to exceed the US safety standards by as much as 1,000 times, causing such side effects as children born with fused fingers and deformed eyes, high cancer rates, etc.
For more details, check out the Oil Pollution of Ecuador Rainforest article.
Source : http://www.tropical-rainforest-animals.com/

Sources of Environmental Pollution

Fossil Fuel Sources of Environmental Pollution

Fossil Fuel Pollution
Photo: Rachel Scopes

In modern industrialized societies, fossil fuels (oil, gas, coal) transcended virtually all imaginable barriers and firmly established themselves in our everyday lives.
Not only do we use fossil fuels for our obvious everyday needs (such as filling a car), as well as in the power-generating industry, they (specifically oil) are also present in such products as all sorts of plastics, solvents, detergents, asphalt, lubricating oils, a wide range of chemicals for industrial use, etc. (8)
Combustion of fossil fuels produces extremely high levels of air pollution and is widely recognized as one of the most important “target” areas for reduction and control of environmental pollution.
Fossil fuels also contribute to soil contamination and water pollution. For example, when oil is transported from the point of its production to further destinations by pipelines, an oil leak from the pipeline may occur and pollute soil and subsequently groundwater. When oil is transported by tankers by ocean, an oil spill may occur and pollute ocean water.
Of course, there are other natural resources whose exploitation is a cause of serious pollution; for example, the use of uranium for nuclear power generation produces extremely dangerous waste that would take thousands of years to neutralize.
But there is no reasonable doubt that fossil fuels are among the most serious sources of environmental pollution.
Power-generating plants and transport are probably the biggest sources of fossil fuel pollution.
Common sources of fossil fuel pollution are: (9)

Industry:

• Power-generating plants
• Petroleum refineries
• Petrochemical plants
• Production and distribution of fossil fuels
• Other manufacturing facilities

Transport:

• Road transport (motor vehicles)
• Shipping industry
• Aircraft

Fossil fuel combustion is also a major source of carbon dioxide (CO2) emissions and perhaps the most important cause of global warming. Learn more about the causes and effects of global warming here.

Other (Non-Fossil Fuel) Sources of Environmental Pollution

Among other pollution sources, agriculture (livestock farming) is worth mentioning as the largest generator of ammonia emissions resulting in air pollution. Chemicals such as pesticides and fertilizers are also widely used in agriculture, which may lead water pollution and soil contamination as well.
Trading activities may be another source of pollution.
For example, it’s been recently noted that packaging of products sold in supermarkets and other retail outlets is far too excessive and generates large quantities of solid waste that ends up either in landfills or municipal incinerators leading to soil contamination and air pollution.
Residential sector is another significant source of pollution generating solid municipal waste that may end up in landfills or incinerators leading to soil contamination and air pollution.

We discuss air pollution causes in more detail here.
Source : http://www.tropical-rainforest-animals.com

Introduction to Environmental Pollution

Although pollution had been known to exist for a very long time (at least since people started using fire thousands of years ago), it had seen the growth of truly global proportions only since the onset of the industrial revolution during the 19th century.

Environmental Pollution
England, 19th Century
Courtesy: Wikimedia.org

The industrial revolution brought with it technological progress such as discovery of oil and its virtually universal use throughout different industries.
Technological progress facilitated by super efficiency of capitalist business practices (division of labour – cheaper production costs – overproduction – overconsumption – overpollution) had probably become one of the main causes of serious deterioration of natural resources.
At the same time, of course, development of natural sciences led to the better understanding of negative effects produced by pollution on the environment.
Environmental pollution is a problem both in developed and developing countries. Factors such as population growth and urbanization invariably place greater demands on the planet and stretch the use of natural resources to the maximum.
It has been argued that the carrying capacity of Earth is significantly smaller than the demands placed on it by large numbers of human populations. And overuse of natural resources often results in nature’s degradation.

It’s interesting to note that natural resources had been stored virtually untouched in the Earth for millions of years.
But since the start of the industrial revolution vast amounts of these resources had been exploited within a period of just a couple of hundred of years at unimaginable rates, with all the waste from this exploitation going straight in to the environment (air, water, land) and seriously damaging its natural processes.

Source  : http://www.tropical-rainforest-animals.com/

Air Pollution

Air pollution, both indoor and outdoor, is a significant cause of health problems worldwide. Urban and rural outdoor environments contain infections, allergens, irritants and chemical toxins that can reduce the quality of life and cause disease. Inhaled air pollution is directed at the the nose, throat and lungs. The exposed airway allows hazardous pollutants to enter the body and all tissues are ultimately exposed.
Air pollution was first noticed as problem of city dwellers, poisoning themselves, but more recently, air pollution is acknowledged as a problem of global significance. The tolerance for environmental destruction is ancient and human history is littered with civilizations that failed because humans exploited natural resources and spoiled their own nest. Humans adapt easily to deteriorating conditions and will persist in following daily routines even when air pollution is severe, traffic is congested, water and food supplies are at risk, and social order is unstable.
Fine-particulate air pollution is known to contribute to cardiovascular and lung disease, increasing the risk of heart attacks and a heart-related death. Researchers at Brigham Young University and Harvard School of Public Health compared changes in air pollution from 1980 to 2000 with residents’ life expectancies, They concluded that a reduction in air pollutants in 51 U.S. cities between 1980 and 2000 added an average of five months to life expectancy. Residents in cities that made the most significant improvements in air quality, such as Pittsburgh, PA,  lived almost 10 months longer. For every microgram per cubic meter decrease in fine-particulate air pollution, life expectancies rose by more than seven months.
Airborne chemicals contaminate food and water. Airborne chemicals contaminate food and water sources. Airborne chemicals are ingested; they collect in the nose and throat and are swallowed, often in mucus that attempts to protect exposed surfaces. Airborne chemicals entering the digestive system include well-known toxins such as pesticides, organophosphate, PCBs, dioxin, arsenic, cadmium, lead, and mercury. In addition occupational exposures to airborne pathogens can be intense and can cause cancer.
While ambient air pollution is a major concern, indoor air can be more polluted than outdoor air. Building materials and furnishings are a source of volatile chemicals. A decrease in indoor air quality is the result of reduced ventilation and efficient construction practices, sealing homes, stores and office buildings from the outdoor environment
Smoking tobacco remains a personal method of producing air pollution that remains popular worldwide, despite overwhelming evidence that tobacco smoke produces a long list of disabling and fatal diseases. It is estimated that 30% of all fatal cancers could be prevented if tobacco smoking were eliminated from the list of air pollutants.
The really sad part of our current predicament is that all the right ideas for creating a healthy environment  have been around for decades and have been clearly articulated in many forms by a host of intelligent people. The right ideas involve unselfish and compassionate behavior. The right ideas involve long-term planning, conservation and deep commitment to preserving the natural world. Without a healthy natural environment, there will be few or no healthy humans.
Our big environmental problems are built from many small, personal decisions - little mistakes that add up over time. If there is a solution, it will emerge from the collective value of millions of better decisions made by individuals all over the globe. The environmental action plan is to think globally and act locally - it does make sense.

Recent environmental disasters

 
Environmental disasters that occurred after January 2000

November 2006 - At least 23 people are killed in a mine in the south of Poland, consequential to a methane explosion. Only three people survive the mining accident.

November 2006 - At least eight people are killed by a series of tornadoes in North-Carolina, USA. Considerable damage is done, and authorities fear the death toll will increase further.

October 2006 - The Greek Isle of Crete is subject to storms. Parts of the isle are flooded and dozens of tourists are evacuated. A number of houses flood and water is pumped out by firemen. Aerial traffic is complicated.

October 2006 - An earthquake of 6,6 on the Richter schale hits Hawaii, causing emergency measures to be taken. The location is relatively sparsely populated, therefore damages are limited. Honolulu experiences power outage, and 3000 people are evacuated from two beach hotels.

October 2006 - Typhoon Xangsane kills at least 16 people in Japan, and in China another person is killed. Earlier, the typhoon caused the death of 76 people in the Phillipines.

September 2006 - Explosion in a mine in southeast Ukraine kills at least 13 people, and injures 36 people. The explosion is caused by a leak in a carbon-gastank.

September 2006 - Explosion in a Mittal Steel mine in Kazachstan kills 18 people. The cause remains unknown, and 40 people are declared missing.

September 2006 – Human rights organisation Christian Aid announces that the continuing drought might cause a famine in Afghanistan that may kill millions of people.

September 2006 – A fire in a waste treatment plant in Maastricht, The Netherlands, causes smoke and smell nuisance.

September 2006 – Illegally deposited waste from oil tanker Probo Koala causes and environmental disaster at Ivory Coast. Seven people die from intoxication, and another 40,000 people fall ill. Oil residues contain toxic substances, such as hydrogen sulphide (H2S). Eight people responsible for the disaster are arrested, and environmental and transport ministers are replaced, followed by a major clean-up operation.

July 2006 – Bombing of an electricity plant during the Lebanon war causes a leakage of 25,000 tons of crude oil from the Lebanese coast to the Mediterranean Sea.

June 2006 – Typhoon Ewiniar hits China, Korea and the Japanese islands and kills at least 40 people. An enormous amount of people needs to be evacuated, and many homes are destroyed by storms and floods caused by heavy rains.

February 2006 - In Bosnia-Herzegovina 18 tons of boiling hot oil pollute the River Neretva in the south. The oil comes from a transformator of a power plant in Jablanica.

January 2006 - Six tons of diesel oil leak into the Yellow River in the province of Henan, China from a power plant and spreads towards the Bohai Sea. Fortunately, not much damage is done to local shrimp fishery, because shrimps are only present in sediments during winter.

January 2006 – Food crisis in Ethiopia, Kenya, Somalia and Djibouti, caused by extreme drought and civil war, results in a famine that victimizes 11 million Africans. In Kenya, at least 30 people die of hunger.

December 2005 - Chinese authorities dump iron and aluminum into the Bei River in the province of Guangdong. It is carried out as a measure to prevent further spreading of cadmium pollution caused earlier that month.

December 2005 - A Slovakian oil tanker containing 42 tons of crude oil catches fire and sinks near Bulgaria in the Danube River. The accident causes a kilometre-wide oil slick, and measures are taken to prevent further oil spills.

November 2005 – A Series of explosions in a petrochemical plant in China pollutes the River Songhua, and leaves the city of Harbin without water for days. In total, the benzene spill kills 5 people, injures another few dozen people, and results in the evacuation of tens of thousands of residents in the area.

October 2005 - A fire in the east wing of the prison complex in Schiphol, The Netherlands, kills 11 people. The Safety Counsel states that fire damage could have been prevented if government services would have followed fire safety regulation. Fire tests indicate that a cigarette fag caused the fire.

October 2005 – Hurricane Wilma hits parts of Mexico and Cuba, results in mudflows, kills 62 people and causes over 20 million dollars damage.

October 2005 – Earthquake in Kashmir, Pakistan kills over 80,000 people, and leaves over 3.3 million homeless. Most people die during landslides caused by the quake. Reconstruction is difficult, and a year later not all structures are repaired. An estimated 66,000 people still do not have a home, and about 40,000 of them stay in refugee camps.

September 2005 - Manure pollutes the River Linde in The Netherlands, between Wolvega and De Blesse. Fish deaths are numerous, and surrounding cities experience smell nuisance. It is suspected that a farmer in Noordwolde spilled manure a few weeks earlier, because of some problems with a liquid manure injection.

September 2005 – Typhoon Longwang kills 96 people at the Japanese coast; en gradually diminishes to a tropical storm.

September 2005 – Hurricane Rita strikes Louisiana, kills seven people directly, and causes many more casualties during evacuations and from indirect consequences (fires, car crashes, illness, poisoning). Eventually, the official death toll is set on 120.

August 2005 - Hurricane Katrina causes devastation in the American cities of New Orleans and Louisiana; beaches erode, more than 1,600 people die, and survivors plunder stores and use violence against each other and against authorities.

July 2005 – Typhoon Haitang strikes Taiwan and China. Heavy squalls and rains cause 13 casualties, and at least 18 people are severely wounded.

July 2005 – Large parts of Bombay, India are flooded, causing more than 1,000 casualties.

June 2005 – Severe monsoon rains in Gujarat, India cause floods, resulting in 123 deaths, and about 250,000 evacuees.

March 2005 – An earthquake near Fukuoka, Japan hurts 70 people severely, and causes light wounds on more than 1,000 people. The many after shocks result in the evacuation of a large number of people.

2005 – Extreme droughts result in failed maize harvest, followed by famine in Malawi, Southeast Africa.

December 2004 - Tanker Selendang Ayu from Malaysia strands near the coast of Alaska, breaks in two, and leaks about 500,000 litres of oil into the ocean.

December 2004 – Indian Ocean earthquake causes tsunami and subsequently kills almost a quarter of a million people (see environmental disasters).

October 2004 – Earthquake in Chuetsu, Japan leaves 3,000 people injured, and many more lose their homes.

March 2004 – Tank car containing bromine tilts near Ekeren, causing a bromine cloud to form and leaking 6000 litres of bromine to the sewers, subsequently flowing into the River Schelde. About 3,000 people are evacuated, and a major clean-up operation starts.

October 2003 – Large fire in the south of California (US) causes 14 casualties. Nearly 3,000 square kilometres of forest is burned, along with more than 3,500 houses.

October 2003 – A fire in San Bernardino Mountains in California (US) kills 6 people, and destroys nearly 1,000 homes. Nearly 400 square kilometre forest is lost.

August 2003 – Extreme heat wave in Europe results in more than 2,000 casualties. On some locations temperatures exceed 40oC.

June 2003 – Iraqi civilians steal a number of uranium containers from a nuclear power plant, and rinse them out in rivers. The barrels are applied to store milk, tomatoes and drinking water. Selling the barrels makes it extremely hard to trace any (see environmental effects of warfare).

June 2003 – Fire destroys nearly 350 square kilometres of land in Santa Catalina Mountains in Arizona (US). Approximately 340 homes are destroyed, and total costs are about 24 million dollar.

December 2002 – Oil tanker Tricolor collides with another ship near the coast of France. During the clean-up operation multiple accidents cause oil spills (see environmental disasters).

November 2002 - Left-wing rebels from Colombia detonated 123 pipelines by means of dynamite. The amount of oil leaking from the pipes is three times that leaking from the oil tanker Exxon Valdez in 1989 (see environmental disasters).

November 2002 – Storms cause some problems for tanker Prestige, resulting in cracking of the tanker, and a 170,000 litre oil spill that flows in the direction of Belgium and The Netherlands.

August 2002 - Chlorine gas is emitted from the Spolana chemical plant in Czechia, near Prague. The direct cause appears to be flooding of the River Elbe, causing water damage that results in leaking storage tanks.

August 2002 - Forest fires, exhaust fumes, industrial discharge and coal and manure burning cause a three kilometre thick blanket of brown smoke over India, Myanmar, South-China, large parts of Southeast-Asia and the Pacific. Smog contains mostly soot, sulphur dioxide and greenhouse gases, and causes floods and crop failure, among other effects.

June 2002 – Major forest fire near Denver, Colorado (US) results in the evacuation of more than 5,000 people. The fire starts as a small campfire and rapidly spreads over more than 200 square kilometres because of extreme drought. More than 40 million dollars of damage repair is required.

June 2002 – Fire in Arizona burns more than 2,000 square kilometres of forest, and more than 30,000 people are evacuated.

October 2001 - Cyanide spill from a ruptures dam pollutes the Asuman River in the west of Ghana. Thousands of cubic metres of water containing cyanide and heavy metals causes many fish, brabs and birds to die, and drinking water in nearby cities is polluted.

September 2001 – Explosion at a nitrogen fertilizer plant in Toulouse, France, causes a big crater to form, and thirty people are killed instantly. More than 10,000 people get hurt, and 40,000 people are left homeless. The plant is completely destroyed.

September 2001 – Terrorist attacks of the World Trade Centre in the US cause about 3,000 casualties, among which are many fire fighters. The event causes an environmental disaster, as an atmospheric plume forms over lower Manhattan (see environmental effects of warfare).

March 2001 - The largest oil platform in the world, the P-36 of Brazilian oil society Petrobras, threatens to tilt over. One leg cracks and the platform moved 35 degress forward. A series of explosions kills two people, and another eight are missing. Measures are taken to keep the hulk from tilting over completely.

Januari 2001 - Oil tanker Jessica strands near the Galapagos Isles, about 1000 kilometres west of Equador. An estimated 800 tons of oil leaks into the sea, and many seaguls and other sea birds die.

May 2000 – Fireworks container explodes in Enschede, The Netherlands, kills 23 people, and injures 950 more people.

May 2000 – Hard winds and extreme drought cause a major fire in New Mexico (US) from what started as a small controlled fire. More than 190 square kilometres of forest fully burned, and more than 400 families lost their homes in the flames.

January 2000 – About 100,000 m3 water with hydrogen cyanide flows from the River Tisza to the Danube River, after a leak in a settling basin in Baia Mare (see environmental disasters).


Bronnen

- BBC news
- Encyclopaedia Brittannica
- Nu.nl
- NRC Handelsblad
- Wikipedia

Read more: http://www.lenntech.com/recent-environmental-disasters.htm#ixzz1Bcz2GKx8

Environmental problems caused by human interference in matter cycles
In the past decades humans have been the cause of extensive environmental pollution. Pollution is not a one-sided term; all kinds of matter has been applied by humans, resulting in a disturbance in natural processes. Disturbances of natural processes are clearly shown, when you take a look at human interference in matter cycles. This has caused various environmental problems, which are important issues today.
I) Hydrological cycle
H2O


There are three ways in which humans cause environmental problems by interfering with the hydrological cycle. Firstly, we remove large quantities of freshwater from rivers, lakes and groundwater supplies. In areas where great amounts of people use the water from groundwater supplies, groundwater may be fully depleted. This effect is enhanced by vegetation removal to create new farmland or underground mines, or to build roads. Secondly, because of vegetation removal, rainwater washes away and it no longer infiltrates, so that the groundwater supplies are not restored. In many cases groundwater supplies will than be filled up with salt water from rivers and lakes. When groundwater is salinated the entire area is influenced. Other effects also occur because of vegetation removal; the risk of flooding is enhanced, and soil erosion and land sliding increase. Finally, people change the quality of water, by adding nutrients and contaminants. This causes the ecological processes that usually purify the water to be disturbed.

Back to the hydrological cycle

II) Nitrogen cycle
N


Humans cause environmental problems, by interfering with the nitrogen cycle in several ways.
During fuel combustion various compounds are released, among which nitrogen oxides (NOx). Nitrogen oxides react with oxygen in air, so that nitrous oxide gas (N2O) is formed. Nitrous oxide is a greenhouse gas, which enhances the earth's temperature when it is present in the atmosphere too extensively. It can also react with ozone in the atmosphere, so that the ozone layer is broken down. The ozone layer is a kind of shell around the earth that consists entirely of ozone. This layer protects the earth and all its life from damaging UV-radiation. When the ozone layer is broken down, humans and animals can experience serious sunburns and skin cancer.
Nitrogen dioxide may also react with hydrogen in the atmosphere, to form nitric acid (HNO3). Nitric acid causes acid deposition, which can damage trees and marine ecosystems, due to increases in the pH of soil and water.
Humans are also responsible for shortages of nitrogen on certain locations. The shortages consist when humans remove nitrogen, to create fertilizers to apply on farmland. As a result, farmland becomes too rich in nutrients and other areas will suffer nitrogen shortages. Vegetation in these areas depletes.
When people want to create new farmland they often burn parts of forests, because the ground underneath these forests is very fertile. While the wood is burned more nitrogen dioxide escapes into air and nutrients are removed from the ground.

Back to the nitrogen cycle

III) Phosphorus cycle
P


Humans also cause environmental problems by interfering with the phosphorus cycle. We remove phosphates on certain locations, to apply it on farmland as fertilizers. On these locations the phosphate supply is moving, causing phosphate levels of surrounding land-soils and groundwater to become too high.
On farmland where phosphates are applied as fertilizers, plants do not absorb all phosphate. The phosphates end up in water and stream towards lakes and reservoirs, where they cause a phenomenon called eutrophication. Eutrophication means that the water is so rich in nutrients that it causes certain water plants, such as green algae, to grow extensively. As a result the oxygen supply in the water depletes, causing fish and other oxygen-dependent organisms to die and bacteria that are not oxygen dependent (anaerobic) to take over.
When people practise extensive wood chopping in forest areas, such as the tropical rain forest, phosphate supplies deplete, because most of the phosphate can be found in the ground under the trees in such areas. When the trees are removed the rain washes phosphates away, causing the ground to become unproductive.
Phosphate supplies are restored very slowly, because most phosphate in soils and water comes from weathering rocks and oceanic sediments.

Back to the phosphorus cycle

IV) Sulphur cycle
S

Today, humans are responsible for the consistence of 90% of the sulphur salts that are found on earth. These salts mainly are mainly formed during industrial processes, such as coal combustion processes, petroleum refining processes and melting processes. Sulphur compounds, such as sulphuric acid, sulfur dioxide and hydrogen sulphide can cause acid deposition on water and soil. This phenomenon causes the pH of water and soil to fall, which can influence life in the soil and water and disturb natural processes.

Back to the sulphur cycle

V) Carbon cycle
C

Humans cause environmental problems by influencing the carbon cycle in two ways.
Firstly, the removal of forests has caused depletion in plants and trees that absorb carbon dioxide. Humans cause great carbon emissions to the atmosphere, which take place during industrial processes, such as coal and oil combustion. These processes serve the generation of energy. As a result of these effects the carbon dioxide levels in the atmosphere have greatly increased. Between 1870 and 1990 the carbon dioxide emissions to air have increased 25%. The carbon dioxide levels in air are now so high, that the uptake by plants and oceans is not fast enough.
Carbon dioxide is a greenhouse gas. This means that increasing carbon dioxide levels in air support the greenhouse effect. The greenhouse effect is a term that is used for climate change on earth, caused by greenhouse gases in the atmosphere. Too much carbon dioxide in the atmosphere can cause the earth to warm up. This will in time cause all kinds of negative effects, such as melting of ice from the Arctic causing floods on other continents.
Secondly, during the industrial revolution humans have used fossil fuels extensively for energy generation, as has been mentioned before. Because fossil fuels consist of dead organic matter it takes a very long time to restore the supplies. Because humans have been burning fossil fuels extensively over the past decades fossil fuel supplies are in danger of being exhausted.


Back to the carbon cycle Back to the matter cycles overview page
To the introduction of freshwater pollution

Acid deposition

Acid deposition is a general name for a number of phenomena, namely acid rain, acid fog and acid mist. This means it can imply both wet and dry (gaseous) precipitation. Acid deposition is a rather well known environmental problem, for example acid fog killed several thousand people in London in 1952.

Acid deposition is concerned with long-range rather than local effects. Pollutants are mixed in the atmosphere and therefore usually cannot be attributed to any local source. Pollutants are generally more dispersed and of lower concentrations than local ground level pollutants.
Acid deposition typically has a pH below 4, but this may be as low as 1.5 under seriously acidic conditions. It primarily consists of two types of compounds, namely sulphuric acid (H₂SO₄) and nitric acid (HNO₃).

Sulphuric acid is formed by conversion of sulphur dioxide emitted from power stations, melting processes, home fires, car exhausts and other sources. It contributes about 70% to the overall acidity of deposition.
Reaction mechanism: SO₃ + H₂O -> H₂SO₄

Nitric acid is formed from nitrogen oxide (NO_x) emissions from fossil fuel combustion. It contributes about 30% to the overall acidity of deposition.
Reaction mechanism: NO₂ + OH^- -> HNO₃

Acid rain has various environmental and health effects, for example:
- Chocking plant leave pores (forest loss)
- Corroding stone and brick walls of buildings and monuments
- Corroding paper and rubber objects
- Altering soil chemistry (soil acidification, loss of plant nutrients)
- Altering the chemical balance of lakes and streams
- Disrupting fish gill operation (fish deaths)
- Deteriorating human breathing disorder (asthma, bronchitis, lung oedema)

When people die of acid deposition it is usually caused by access mucous production in the bronchi, leading to chocking from a lack of oxygen, or a heart attack.

Acid deposition in various countries

Acid deposition is a transboundary environmental problem. This basically means that emissions in one country may affect forests and structures in a neighbouring country. Therefore, international agreements were made, such as the Sulphur emissions Reduction Protocol (1979) and the Convention on Long-Range Transboundary Air Pollution (1983).

Some examples of countries that experience(d) acid deposition, either from their own sources or from transboundary air pollution:
- Britain: smog episodes around London, particularly in 1952
- Germany: acid mists in central Germany and the Black Forest area, acid cold smog from Poland and former Czechoslovakia in 1985
- Greece: intense industrialization in the Athens area causes deterioration of ancient monuments such as the Parthenon by acid deposition
- Italy: damage to Venice structures from acid deposition
- Scandinavia: 15% of acid rain caused by Great-Britain
- Scotland: episodes of black acid snow in the Cairngorm mountains in 1984
- The Netherlands: corrosion of bells of the Utrecht Dom tower since 1951
- United States: acid rains disrupts forest ecosystems and pollutes surface waters, industrial fossil fuel combustion processes are adapted to prevent sulphur dioxide emissions

Sources

Graham and Trotman, 1983, Acid rain – A review of the phenomenon in the EEC & Europe, Environmental Resources Ltd

Pearce, 1987, Acid rain, what is it and what is it doing to us?, Richard Clay Ltd

http://bqs.usgs.gov/acidrain

http://en.wikipedia.org/wiki/Acid_deposition