Referat Water pollution

ENGLISCH - REFERAT

Zusammenfassung

Water pollution

It's easy to dispose of waste by dumping it into a river or lake. The waste will be carried away by the current, but it will reappear downstream, perhaps in changed form, or diluted, and it will never disappear. Freshwater bodies like rivers, seas or lakes can clean themselves and break down some waste materials, but not so much like today's society dumps into the water. The result is water pollution which can put the ecosystem out of balance.

Sometimes nature itself produces these imbalances : for example : In the water flowing in the highly saline terrain of the prairies, or in water that comes out of highly mineralized springs no fish can stay alive.

But the most pollutants in the water comes from municipal, agricultural and industrial wastes. These wastes include often toxic chemicals, which natural processes can not break down. Only tiny amounts of this substances can cause serious harm. For example the Great Lakes, and the St. Lawrence River are contaminated by such chemicals.

What are the sources of water pollution ?

There are two general categories :

direct contaminant sources

indirect contaminant sources

1) : Effluents from factories, refineries, waste treatment plants. In the USA and in other countries it's regulated, that this pollutants cannot come into urban water supplies, but there are countries, where this pollutants can get into the drinking water.

2) : Contaminants that enter the water supply from soils water and groundwater. In the soil - water and in the groundwater are residues of human agricultural practices (fertilizers, pesticides,.) and of industrial waste. Indirect contaminant sources include also atmospheric contaminants (they come into the water supply via the rain). Atmospheric contaminants are gaseous emissions from cars, factories or even bakeries.

What are the ways we can take to decrease those problems ?

Science provides many solutions to minimizing the water pollution and to clean up past problems, but this will come with some costs. That means, that we would not only have to pay money, no, everybody would have to do something in his or her everyday lives. There are choices we make each day which affect the quantity of pollutants.

We should take care to recycle materials whose production creates pollution

We should act responsibly with household chemicals and their disposal

We shouldn't buy heavily packaged foods

We shouldn't buy boxes, cartons or bottles which were made with polluting dyes

We shouldn't drive so much with our cars, we should ride rather a bicycle or walk

In fact, our lives are based upon practices which are much "dirtier", than those of our ancestors. The answer to the question "What are the ways we can take to decrease those problems ?" seems to be, that we have to do many small changes in our daily practices, and to pay more for goods and services, so that manufacturers and drivers of cars will have cleaner devices with which to conduct their activities.

How do we clean up oil slicks ?

There are three different ways to clean up oil slicks :

chemical dispersion

natural dispersion

collection

1) : The main problem with the oil slick is the way they stick together and swim on the surface of the water. So chemicals have been developed, which are sprayed on the oil and break the slick apart. When it is broken up, the slick dilutes into the water without any more problems. 

But there is one more problem :

The dispersants cannot be used on viscous oils, which include crude oils, and all heavy fuel oils.

And, crude oils, that could be dispersed, change their characteristics within a few hours in cold water, so they can no longer be dispersed. So chemical dispersion has to be very fast, and dispersant - spraying airplanes or helicopters are used.

Scientist also have created an organism, which feed on oil. Laboratory tests with the organism have been very successful, but scientist don't want to release the organism into the environment, because it could be dangerous.

Modern dispersants are much less toxic than earlier types, but they are still a pollutant in themselves. So before they are used, it must be decided, if they would cause more damage than the oil slick would if it was left untreated. If  dispersants are used or not depends on the depth of the water, on how strong the currents are, and which animals and plants live in the water.

2) : Oil slicks can just be left to disperse and break down naturally, which can be helped by certain weather conditions, for example storms.

3) : Collecting the oil means to remove it from the environment (chemical and natural dispersion techniques don't do this), and it can also be used again afterwards.

The first stage to collect the oil is to contain it. This is usually done with booms, there are inflatable ones which are easy to store, solid booms which are more resistant to damage, and booms made out of natural materials like fences or bales of hay, which are used, when there are no others.

The second stage is to collect the oil. This is done with skimmers or sorbants.

There are two types of skinners : The first ones work like big hoovers and suck the oil off the water. The problem is, that 90 percent of the liquid collected is water.

The second type works with adhesion. A material is pulled through the oil slick and the oil sticks to the material and is carried away. Later the oil is squeezed out of the material.

Sorbants are materials which absorb oil, for example straw, sheets or mops. They cannot collect large volumes of oil, so they are used in the final stages of cleaning when only less oil is left.

There are ships in which is integrated a complete oil collection system, for example the AL WAASIT, which was used to clean the water after the Gulf War. The AL WAASIT can clean up half a square mile per day.

Folien

Water pollution

It's easy to dispose of waste (Müll loswerden) by dumping it into a river or lake, but it will never disappear. Only tiny amounts (Mengen) of toxic chemicals can cause (verursachen) serious harm. For example the Great Lakes, and the St. Lawrence River are contaminated (verschmutzt) by such chemicals.

What are the sources of water pollution ?

There are two general categories :

1) direct contaminant sources : Effluents (Abwässer) from factories, refineries, waste treatment plants (Müllentsorgungsanlagen).

2) indirect contaminant sources : a) Contaminants (Verschmutzungen) in the soil - water (Bodenwasser) and in the groundwater ( = residues (Rückstände) of human agricultural practices (fertilizers (Düngemittel), pesticides,.) and of industrial waste).

b) Atmospheric contaminants ( = gaseous (gasförmige) emissions from cars, factories or even bakeries).

What are the effects of water pollution ?

Pollution can hurt the life cycle of animals and plants which live in the water. The pollutants (Schadstoffe) can also get into the food of humans, and they can get very ill (stomachache, headache, nervous diseases). There are many different effects of water pollution :

n    Effects of untreated human waste

n    Effects of run - off pollution

n    Effects of oil pollution and antifreeze

n    Contaminated ground water effects

n    Fertilizers and other chemicals

n    Effects of factory pollution

n    Effects of garbage from private offices and homes

n    Effects of Eutrophication (to much nutrients (Nährstoffe) in the water)

n    Effects of acid rain

What are the ways we can take to decrease (vermindern) those problems ?

In fact, our lives are based upon practices which are much "dirtier", than those of our ancestors (Vorfahren). Science provides (liefert) many solutions to minimize the water pollution and to clean up past problems. We would not only have to pay money, everybody would have to do many small changes in his or her daily practices.  

1) We should take care to recycle materials whose production creates pollution

2) We should act responsibly with household chemicals and their disposal (Entsorgung)

3) We shouldn't buy heavily packaged foods

4) We shouldn't buy boxes, cartons or bottles which were made with polluting dyes (Farben)

5) We shouldn't drive so much with our cars, we should rather ride a bicycle or walk

How do we clean up oil slicks (Ölteppiche) ?

There are three different ways to clean up oil slicks :

1) chemical dispersion (Auflösung, Zerstreuung)

The main problem with the oil slick is the way they stick together and swim on the surface (Oberfläche) of the water. So chemicals have been developed (entwickelt), which are sprayed on the oil and break the slick apart. When it is broken up, the slick dilutes (sich vermischen) into the water without any more problems. 

But there is one more problem :

The dispersants cannot be used on viscous (zähflüssig) oils, which include crude (roh) oils, and all heavy fuel oils (Heizöle).

And, crude oils, that could be dispersed (aufgelöst), change their characteristics within a few hours in cold water, so they can no longer be dispersed. So chemical dispersion has to be very fast, and dispersant - spraying airplanes or helicopters are used.

Scientist also have created an organism, which feed on oil. Laboratory tests with the organism have been very successful, but scientist don't want to release the organism into the environment, because it could be dangerous.

Modern dispersants (Auflösungsmittel) are much less toxic than earlier types, but they are still a pollutant in themselves. So before they are used, it must be decided, if they would cause more damage than the oil slick would if it was left untreated. If  dispersants are used or not depends on the depth of the water, on how strong the currents (Strömungen) are, and which animals and plants live in the water.

2) natural dispersion

Oil slicks can just be left to disperse and break down naturally, which can be helped by certain weather conditions, for example storms.

3) collection

Collecting the oil means to remove it from the environment (chemical and natural dispersion techniques don't do this), and it can also be used again afterwards.

The first stage to collect the oil is to contain (umfassen, einkreisen) it. This is usually done with booms (Bojen). There are inflatable (aufblasbar) ones which are easy to store (lagern), solid (fest) booms which are more resistant to damage, and booms made out of natural materials like fences (Zäune) or bales of hay (Heuballen).

The second stage is to collect the oil. This is done with skimmers or sorbants.

There are two types of skimmers : The first ones work like big hoovers (Staubsauger) and suck (saugen) the oil off the water. The problem is, that 90 percent of the liquid collected is water.

The second type works with adhesion (Haftung). A material is pulled through the oil slick and the oil sticks to the material and is carried away. Later the oil is squeezed out (ausgepresst) of the material.

Sorbants are materials which absorb (aufsaugen) oil, for example straw, sheets or mops. They cannot collect large volumes of oil, so they are used in the final stages of cleaning when only less oil is left.

There are ships in which is integrated a complete oil collection system, for example the AL WAASIT, which was used to clean the water after the Gulf War. The AL WAASIT can clean up half a square mile (Quadratmeile) per day.

Zettel zum Austeilen

WATER POLLUTION

Waste, which is dumped into rivers or lakes will never disappear. It will perhaps be carried away by the current (Strömung), but it will reappear downstream, often in changed form, or diluted (verdünnt). Freshwater bodies like seas, lakes or rivers can clean themselves and break down some waste materials, but not as much as today's society dumps into the water. The result is water pollution, which can put the whole ecosystem out of order.

Most of the pollutants (Schadstoffe) come from municipal, agricultural and industrial wastes. These wastes include often toxic chemicals, which natural processes cannot break down. Only very tiny amounts (Mengen) of this chemicals can cause (verursachen) serious harm. For example the Great Lakes and the St. Lawrence River are contaminated (verschmutzt) by such toxic substances.

What are the sources of water pollution ?

There are two general categories of sources :

Direct contaminant sources : are effluents (Abwässer) from factories, refineries and waste treatment plants (Müllentsorgungsanlagen). In some countries this pollutants can be found in the drinking water.

Indirect contaminant sources : are contaminants (Verunreinigungen), which enter the water supply from soil water (Bodenwasser) or groundwater. In this waters are residues (Rückstände) of human agricultural practices, for example fertilizers (Düngemittel), and of industrial wastes. Indirect contaminant sources are also atmospheric contaminants, which come into the water supply via the rain, and which are gaseous (gasförmige) emissions from cars, factories or even bakeries.

What are the effects of water pollution ?

Water pollution is very dangerous and can cause serious harm. For example, if oil was to spill (ausschütten) in the arctic, heat from the oil could melt the ice and influence temperature levels around the world. Pollution can also hurt the life cycle of animals and plants which live in the water. The pollutants can also get into the food of humans, and they can get very ill (stomachache, headache, nervous diseases) just after eating a little peace of it. There are many different effects of water pollution :

n    Effects of untreated human waste : Normally human waste goes through treatment plants, but, for example during a heavy rain storm, it can get into rivers or lakes and can be dangerous for animals.

n    Effects of run - off pollution : When rain runs off the land it picks up dirt and carries it into the water. There the dirt can settle and keep sunlight from reaching aquatic plants, which will die if they don't get enough sunlight.

n    Effects of oil pollution and antifreeze : Oil is one of the most devastating (vernichtend) pollutants of water. If it gets into the water, animals like birds, mammals (Säugetiere) and fish can be killed if they ingest (zu sich nehmen, aufnehmen) it. The oil also coats (überziehen) the feathers of the birds, so that they can not fly or stay warm any more and die.

n    Contaminated ground water effects : When contaminated water gets into the ground, people can become very ill.

n    Fertilizers and other chemicals : When rain water runs off farm areas, where fertilizers or pesticides are used, they can get into the water. When the rain water reaches rivers or lakes, the plants in there will grow quicker. If there are more pants, there grow also more bacteria, because bacteria eat dead plants. The bacteria need oxygen to survive, and so there will be less oxygen for fish and other animals in the water. Chemicals in the water can also cause tumors, for example in the Great Lakes many fish suffer from (leiden an) tumors. Chemicals in the water can be also dangerous for humans, for example when nitrates get into the drinking water.

n    Effects of factory pollution : Many factories have pipes that drain (ablassen) chemicals into rivers or streams. This chemicals can damage aquatic life or warm the river, which decreases (reduzieren) the amount of oxygen in the water.

n    Effects of garbage from private offices and homes : Many people dump household products into rivers, lakes or oceans. This waste is very dangerous, because dolphins and ducks might be killed when there is plastic in the water, and aluminum cans can cut the animals and fish.

n    Effects of Eutrophication : Eutrophication occurs (tritt auf) when there are to much nutrients (Nährstoffe) in the water, which cause abnormal plant growth. The amount of oxygen in the water is decreased.

n    Effects of acid rain : Acid rain can fall directly on lakes, rivers, or oceans, or it gets into the water after it has fallen on land. Acid rain is very dangerous, because the lakes, rivers or oceans will become acidic (the pH value goes down), and animals will be hurt or killed.

What are the ways we can take to decrease (vermindern) those problems ?

In fact, our lives are based upon practices which are much "dirtier", than those of our ancestors (Vorfahren). Science provides (bereitstellen, liefern) many solutions to minimize the water pollution and to clean up past problems. Of course this would come with some costs, but the most important thing seems to be, that everybody of us has to do many small changes in his/her daily practices. We make choices each day, which affect (beeinflusst) the quantity (Menge) of pollutants in our environment. There are many things we should do :

We should take care to recycle materials whose production creates pollution

We should act responsibly (verantwortungsvoll) with household chemicals (Chemikalien im Haushalt) and their disposal (Entsorgung)

We shouldn't buy heavily packaged foods

We shouldn't buy boxes, cartons or bottles, which are made with polluting dyes (Farben)

We shouldn't drive so much with our cars, we should rather walk or ride a bicycle

How do we clean up oil slicks (Ölteppich, Ölfleck) ?

There are three different ways to clean up oil slicks :

1) Chemical dispersion (Zerstreuung, Auflösung) :

The main problem with the oil slick is the way how they stick together and swim on the surface (Oberfläche) of the water. So chemicals have been developed (entwickelt), which are sprayed on the oil and break the slick apart. Once they are broken up, the slicks dilute (sich vermischen, verdünnen) into the water without any problems. There are just some disadvantages (Nachteile) : The chemicals can not be used on viscous (zähflüssig) oils, which include crude (roh) oil, and all heavy fuel oils (Heizöle). Crude oils, which could be dispersed (aufgelöst), change their characteristics within a few hours in cold water and can no longer be dispersed. Because of that the dispersion with the chemicals has to be very quick and dispersant - spraying airplanes or helicopters are used.

Scientist have also developed an organism, which feed on oil. Laboratory test with it have been very successful, but scientist don't want to release the organism into nature, because it could be dangerous.

Modern dispersants are much less toxic than earlier types, but they are still a pollutant in themselves. If they are used or not, depends on the depth of the water, on how strong the currents are, and which animals and plants live in the water.

2) Natural dispersion :

Oil slicks can just be left to disperse and break down naturally, which can be helped by certain weather conditions, for example storms.

3) Collection of the oil

Collection means that the oil is removed from the environment (chemical and natural dispersion techniques don't do this), and also that it can be used again afterwards.

The first stage to collect the oil is to contain (umfassen, einschließen) it. This is done with booms (Bojen), which can be inflatable (aufblasbar), solid, or made out of natural materials like fences (Zäune) or bales of hay (Heuballen).

The second stage is to collect the oil. This is done with skimmers or sorbants. Skimmers can work like big hoovers (Staubsauger), or with adhesion (Haftung), that means that a material, to which the oil sticks, is pulled through the oil slick.

Sorbants are materials which absorb (aufsaugen) oil, for example straw, sheets (Laken), or mops. They can not collect large volumes of oil, so they are used in the final stages of cleaning, when only less oil is left.

There are ships in which is integrated a complete oil collection system, for example the Al Waasit, which was used to clean water after the Gulf War. The Al Waasit can clean up half a square mile (Quadratmeile) per day.

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