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i humbly need an out sketch of seminar on the topic water pollution including the subtopic causes of water pollution.... and please do kindly tell me about the terms biochemical oxygen demand,and eutrophication (not as in the text !)which should be include in seminar and help with the guidelines to appear for a seminar and how should i prepare for the same. have a good day and i expect my answer on 22/1/2014 wednesday....hope you will answer me as soon as you can

What is water pollution?

Water pollution is the contamination of water bodies (e.g. lakes, rivers, oceans, aquifers and groundwater), very often by human activities.Water pollution occurs when pollutants (particles, chemicals or substances that make water contaminated) are discharged directly or indirectly into water bodies without enough treatment to get rid of harmful compounds. Pollutants get into water mainly by human causes or factors.

          Water pollution is the second most imperative environmental concern along with air pollution.

Any change or modification in the physical, chemical and biological properties of water that will have a detrimental consequence on living things is water pollution.
            The water pollution problem Water covers over 70% of the Earth’s surface. It is a very important resource for people and the environment.
             Water pollution affects drinking water, rivers, lakes and oceans all over the world. In many developing countries, it is usually a leading cause of death, by people drinking from polluted water sources.
            More to this, water pollution affects not only individual living species, but also populations and entire functioning ecosystems that exists in the waters.
            Humans have now realised the importance of clean water as a foundation for life. In recent time, more and more organisations and councils are working hard to educate, protect, restore waterways and encourage practices that help keep waters from contamination, and also to preserve water ecosystems from destruction.
            In this session, we shall learn all about water pollution, the types of water pollution, causes of water pollution, effects and some preventive practices that we can all use to help deal with water pollution.

Types of water pollution

There are many types of water pollution because water comes from many sources. Here are a few types of water pollution:

1. Nutrients Pollution
Some wastewater, fertilizers and sewage contain high levels of nutrients. If they end up in water bodies, they encourage algae and weed growth in the water. This will make the water undrinkable, and even clog filters. Too much algae will also use up all the oxygen in the water, and other water organisms in the water will die out of oxygen from starvation.

2. Surface water pollution
Surface water includes natural water found on the earth's surface, like rivers, lakes, lagoons and oceans. Hazardous substances coming into contact with this surface water, dissolving or mixing physically with the water can be called surface water pollution.

3. Oxygen Depleting
Water bodies have micro-organisms. These include aerobic and anaerobic organisms. When to much biodegradable matter (things that easily decay) end up in water, it encourages more microorganism growth, and they use up more oxygen in the water. If oxygen is depleted, aerobic organisms die, and anaerobic organism grow more to produce harmful toxins such as ammonia and sulfides.


4. Ground water pollution
When humans apply pesticides and chemicals to soils, they are washed deep into the ground by rain water. This gets to underground water, causing pollution underground.

This means when we dig wells and bore holes to get water from underground, it needs to be checked for ground water pollution.

5. Microbiological
In many communities in the world, people drink untreated water (straight from a river or stream). Sometimes there is natural pollution caused by microorganisms like viruses, bacteria and protozoa. This natural pollution can cause fishes and other water life to die. They can also cause serious illness to humans who drink from such waters.

6. Suspended Matter
Some pollutants (substances, particles and chemicals) do not easily dissolve in water. This kind of material is called particulate matter. Some suspended pollutants later settle under the water body. This can harm and even kill aquatic life that live at the floor of water bodies.

7. Chemical Water Pollution
Many industries and farmers work with chemicals that end up in water. These include chemicals that are used to control weeds, insects and pests. Metals and solvents from industries can pollute water bodies. These are poisonous to many forms of aquatic life and may slow their development, make them infertile and kill them.

8. Oil Spillage
Oil spills usually have only a localized affect on wildlife but can spread for miles. The oil can cause the death of many fish and stick to the feathers of seabirds causing them to lose the ability to fly.

Other causes of water pollution:

Sewage and waste water
           Everyday, we cook, do laundry, flush the toilet, wash our cars, shower and do many things that use water. Think about how we use water in schools, hospitals and public places.

            Where do you think all the water, liquid waste, toilet and urine ends up? In many developed communities, this waste water and soluble waste (called sewage) is treated, cleaned and dumped into the sea. Even though they are treated, they are never the same as fresh water.

           In some not-so-developed countries, the sewage is not treated, but quickly dumped into the sea or water bodies. This is VERY dangerous because they contaminate the environment and water bodies and bring many deadly diseases to us.

Septic Tanks
           Every domestic (home) toilet is connected to septic tank usually located outside the house. Each time poop is flushed down the toilet, it goes into this tank, where the solid part is separated from the liquid part. Biological processes are used to break down the solids and the liquid is usually drained out into a land drainage system. From this stage, it can escape into the soil and nearby water bodies.

Ocean and marine dumping
           Again, think of the rubbish we all make each day. Paper waste, food waste, plastic, rubber, metallic and aluminum waste. In some countries, there are deposited into the sea. All these waste types take time to decompose. Example, it is know that paper takes about 6 weeks, aluminum takes about 200 years and glass takes even more. When these end up in the sea, they harm sea animals and cause a lot of deaths.

Underground storage and tube leakages
              Many liquid products (petroleum products) are stored in metal and steel tubes underground. Other sewage systems run in underground tubes. Overtime, they rust and begin to leak. If that happens, they contaminate the soils and the liquids in them end up in many nearby water bodies.

Atmospheric
            Atmospheric deposition is the pollution of water bodies caused by air pollution. Each time the air is polluted with sulphur dioxide and nitrogen oxide, they mix with water particles in the air and form a toxic substance. This falls as acid rain to the ground, and gets washed into water bodies. The result is that, water bodies also get contaminated and this affects animals and water organisms.
    
Effects of water pollution.

 The effects of water pollution are varied and depend on what chemicals are dumped and in which locations.

Many water bodies near urban areas (cities and towns) are highly polluted. This is the result of both garbage dumped by individuals and dangerous chemicals legally or illegally dumped by manufacturing industries, health centers, schools and market places.

Death of aquatic (water) animals
              The main problem caused by water pollution is that it kills life that depends on these water bodies. Dead fish, crabs, birds and sea gulls, dolphins, and many other animals often wind up on beaches, killed by pollutants in their habitat (living environment).

Disruption of food-chains
              Pollution disrupts the natural food chain as well. Pollutants such as lead and cadmium are eaten by tiny animals. Later, these animals are consumed by fish and shellfish, and the food chain continues to be disrupted at all higher levels.

Diseases
              Eventually, humans are affected by this process as well. People can get diseases such as hepatitis by eating seafood that has been poisoned. In many poor nations, there is always outbreak of cholera and diseases as a result of poor drinking water treatment from contaminated waters.

Destruction of ecosystems
                 Ecosystems (the interaction of living things in a place, depending on each other for life) can be severely changed or destroyed by water pollution. Many areas are now being affected by careless human pollution, and this pollution is coming back to hurt humans in many ways.


Prevention of water pollution.


Dealing with water pollution is something that everyone (including governments and local councils) needs to get involved with. Here are a few things you can do to help. Learning about the issue (like you are doing) is the greatest and most important step to take. Here are a few more:

1.Never throw rubbish away anyhow. Always look for the correct waste bin. If there is none around, please take it home and put it in your trash can. This includes places like the beach, riverside and water bodies.

2. Use water wisely. Do not keep the tap running when not in use. Also, you can reduce the amount of water you use in washing and bathing. If we all do this, we can significantly prevent water shortages and reduces the amount of dirty water that needs treatment.

3. Do not throw chemicals, oils, paints and medicines down the sink drain, or the toilet. In many cities, your local environment office can help with the disposal of medicines and chemicals. Check with your local authorities if there is a chemical disposal plan for local residents.

4. Buy more environmentally safe cleaning liquids for the use at home and other public places. They are less dangerous to the environment.

5. If you use chemicals and pesticides for your gardens and farms, be mindful not to overuse pesticides and fertilizers. This will reduce runoffs of the material into nearby water sources. Start looking at options of composting and using organic manure instead.

6. If you live close to a water body, try to plants lots of trees and flowers around your home, so that when it rains, chemicals from your home does not easily drain into the water.

What is Eutrophication?


It is actually, the process by which a body of water becomes enriched in dissolved nutrients that stimulate the growth of aquatic plant life, resulting in the depletion of dissolved oxygen. This is considered a problem in coastal areas, when there is an overproduction of algae.

Effects of eutrophication are:-
1.} Excessive growth of algae in the water bodies such as rivers etc.
2.} Depletion of oxygen in the water which results in the death of fishes etc. and thus a clean water body turns into a stinking drain.

Ways to Prevent Eutrophication
 
              Eutrophication is the extreme growth of algae and marine plants as well as the increase of organic sludge and unpleasant odours in pods, dams and other water areas. Some of the measures to be taken to prevent Eutrophication are to remove any unnecessary waste materials near the pods or dams, spraying the algae with the right chemicals, avoiding sewage waste from flowing to the pods and most of all a close regulation on cleanliness.

BOD

Biological Oxygen Demand (BOD) is a measure of the amount of oxygen consumed by microorganisms (bacteria) in water. Microorganisms use oxygen to consume organic matter. The more microorganisms in the water, the more oxygen they consume. A high BOD indicates high levels of organic matter and bacteria.



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