Daffodil International University
Faculty of Science and Information Technology => Environmental Science and Disaster Management => Topic started by: sazzadte on November 13, 2011, 06:53:59 PM
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Various pollution in Global
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Groundwater pollution
Interactions between groundwater and surface water are complex. Consequently, groundwater pollution, sometimes referred to as groundwater contamination, is not as easily classified as surface water pollution.[ By its very nature, groundwater aquifers are susceptible to contamination from sources that may not directly affect surface water bodies, and the distinction of point vs. non-point source may be irrelevant. A spill or ongoing releases of chemical or radionuclide contaminants into soil (located away from a surface water body) may not create point source or non-point source pollution, but can contaminate the aquifer below, defined as a toxin plume. The movement of the plume, called a plume front, may be analyzed through a hydrological transport model or groundwater model. Analysis of groundwater contamination may focus on the soil characteristics and site geology, hydro geology, hydrology, and the nature of the contaminants.
Thermal pollution
Thermal pollution is the rise or fall in the temperature of a natural body of water caused by human influence. Thermal pollution, unlike chemical pollution, results in a change in the physical properties of water. A common cause of thermal pollution is the use of water as a coolant by power plants and industrial manufacturers. Elevated water temperatures decreases oxygen levels (which can kill fish) and affects ecosystem composition, such as invasion by new thermophilic species. Urban runoff may also elevate temperature in surface waters.Thermal pollution can also be caused by the release of very cold water from the base of reservoirs into warmer rivers.
Transport and chemical reactions of water pollutants
Most water pollutants are eventually carried by rivers into the oceans. In some areas of the world the influence can be traced hundred miles from the mouth by studies using hydrology transport models. Advanced computer models such as SWMM or the DSSAM Model have been used in many locations worldwide to examine the fate of pollutants in aquatic systems. Indicator filter feeding species such as copepods have also been used to study pollutant fates in the New York Bight, for example. The highest toxin loads are not directly at the mouth of the Hudson River, but 100 kilometers south, since several days are required for incorporation into planktonic tissue. The Hudson discharge flows south along the coast due to coriolis force. Further south then are areas of oxygen depletion, caused by chemicals using up oxygen and by algae blooms, caused by excess nutrients from algal cell death and decomposition. Fish and shellfish kills have been reported, because toxins climb the food chain after small fish consume copepods, then large fish eat smaller fish, etc. Each successive step up the food chain causes a stepwise concentration of pollutants such as heavy metals (e.g. mercury) and persistent organic pollutants such as DDT. This is known as biomagnification, which is occasionally used interchangeably with bioaccumulation.
Control of pollution
Domestic sewage is 99.9 percent pure water, while the other 0.1 percent are pollutants. Although found in low concentrations, these pollutants pose risk on a large scale.[22] In urban areas, domestic sewage is typically treated by centralized sewage treatment plants. In the U.S., most of these plants are operated by local government agencies, frequently referred to as publicly owned treatment works (POTW). Municipal treatment plants are designed to control conventional pollutants: BOD and suspended solids. Well-designed and operated systems (i.e., secondary treatment or better) can remove 90 percent or more of these pollutants. Some plants have additional sub-systems to treat nutrients and pathogens. Most municipal plants are not designed to treat toxic pollutants found in industrial wastewater.
Industrial waste water
Main article: Industrial wastewater treatmentDissolved air flotation system for treating industrial wastewater.Some industrial facilities generate ordinary domestic sewage that can be treated by municipal facilities. Industries that generate wastewater with high concentrations of conventional pollutants (e.g. oil and grease), toxic pollutants (e.g. heavy metals, volatile organic compounds) or other nonconventional pollutants such as ammonia, need specialized treatment systems. Some of these facilities can install a pre-treatment system to remove the toxic components, and then send the partially-treated wastewater to the municipal system. Industries generating large volumes of wastewater typically operate their own complete on-site treatment systems.
Agricultural waste water Main article:
Agricultural waste water treatment.Riparian buffer lining a creek in Iowa.Non point source controls.Sediment (loose soil) washed off fields is the largest source of agricultural pollution in the United States.[ Farmers may utilize erosion controls to reduce runoff flows and retain soil on their fields. Common techniques include contour plowing, crop mulching, crop rotation, planting perennial crops and installing riparian buffers.Nutrients (nitrogen and phosphorus) are typically applied to farmland as commercial fertilizer; animal manure; or spraying of municipal or industrial waste water (effluent) or sludge. Nutrients may also enter runoff from crop residues, irrigation water, wildlife, and atmospheric deposition. Farmers can develop and implement nutrient management plans to reduce excess application of nutrients.pp. To minimize pesticide impacts, farmers may use Integrated Pest Management (IPM) techniques (which can include biological pest control) to maintain control over pests, reduce reliance on chemical pesticides, and protect water quality.
Construction site storm water.Silt fence installed on a construction site.Sediment from construction sites is managed by installation of:.erosion controls, such as mulching and hydroseeding, andsediment.controls, such as sediment basins and silt fences.Discharge of toxic chemicals such as motor fuels and concrete washout is prevented by use ofspill prevention and control plans, and
specially designed containers (e.g. for concrete washout) and structures such as overflow controls and diversion berms.
Urban runoff (stormwater)
Effective control of urban runoff involves reducing the velocity and flow of storm water, as well as reducing pollutant discharges. Local governments use a variety of storm water management techniques to reduce the effects of urban runoff. These techniques, called best management practices (BMPs) in the U.S., may focus on water quantity control, while others focus on improving water quality, and some perform both functions.Pollution prevention practices include low impact development techniques, installation of green roofs and improved chemical handling (e.g. management of motor fuels & oil, fertilizers and pesticides).[34] Runoff mitigation systems include infiltration basins, bio retention systems, constructed wetlands, retention basins and similar devices.Thermal pollution from runoff can be controlled by storm water management facilities that absorb the runoff or direct it into groundwater, such as bio retention systems and infiltration basins. Retention basins tend to be less effective at reducing temperature, as the water may be heated by the sun before being discharged to a receiving stream
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It is a nice post which helps to enrich our knowledge in various contaminations on earth. Thank you.
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Nice post. Thanks for sharing.
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Very informative post. Thanks for sharing.
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thx if earth sustain we all safe hopefully because everywhere starting to earth quack, land spaces,war, storm etc disaster.
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we must try to avoid the pollutions. nice informative post.
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Thanks for the post.
Waiting for more information...
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Really nice and very much informative post. The world now becoming more polluted. If we can take the correct action now then the world become very bad place for the human to lead a happy and healthy life. So, we all try to keep the pollution.
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the main problem is our populatin if its control then everything comes systematically
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human is pollute the earth more
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Pollution in earth is mainly created by man. so we should aware of it.
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nice post
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ya madam if earth exist we exist
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good share
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Nice post. It will helps to enrich our knowledge about various Pollution in Earth.
Pollution is mainly happens in three way.
1.Air pollution,
2. Water pollution,
3. Soil pollution.
But the prevention of every pollution is same. We need to be aware to prevent all type of pollution.
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We actually have not enough aware about the bad effects of pollution, if we area aware and know the bad effects of pollution then we all try to remove the pollution at any how. Then we are try to keep away that pollution remove from our country.
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Informative.
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WE people are mainly responsible for the pollution of Earth.
And it is our duty to keep our Universes neat and clean. So we all should be aware about the pollution. And try to avoid pollution.
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Nice post. We Bangladeshi people usually use ground water as drinking water. Now a day’s underground water is also polluting by surface contamination. The rainwater infiltrate to the ground reserve and it dissolves some of mineral compounds on its way. Radiation contamination is also a grate factor.
thanks.......
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Nice post
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Nice post..... But i think now a days population is no longer treated as a problem rather resource. Uncontrolled and unnecessary use of energy might be the reason of these pollution.
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very informative
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Really very informative post...............
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We make our earth polluted. We have to become more conscious About it. We should be careful for our future generation.
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Why don't you add the sound pollution. Everyday we have to bear this hassle. In developed country the drivers seldom blow the horn. But in our country they keep blowing the horn continuously. And the negative effects of it are very much known to us all..
Amin Tasnim
Lecturer BBA and Economics
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Toxic Pollution
Toxic pollution poses health risks to over 100 million people, particularly children, in low- and middle-income countries. This is a finite problem that can be solved in our life.
If we can not prevent or reduce the various pollution then we can not lead a healthy life.
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extremely valuable post
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We the people live in a polluted country...........so we should always try to reduce or prevent the pollution from the earth.
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God make the earth beautiful for us. But we people consciously or unconsciously polluted our beautiful earth regularly. So to keep our earth beautiful and suitable for survive we have to become more conscious About it.
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Good post.
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The pollution of our environment increasing day by day. Earth is polluted by various way. Every element environment such as water, soil, air are polluted in different way. So We all have to be conscious to prevent our environment pollution.
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Today we are experiencing unanimous threats over the earth, which is now a prime concern. Pollution of earth is increasing at an alarming rate. we can not let the world be destroyed like this!!!!!
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Soil pollution: Which can also be called soil contamination, is a result of acid rain, polluted water, fertilizers etc., which leads to bad crops. Soil contamination occurs when chemicals are released by spill or underground storage tank leakage which releases heavy contaminants into the soil.
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good post
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There are some economic policy that could be undertaken to deal with this externality problem . But in our country the Government does not take any action. But this problem should be solved for our better life. We should all pay attention on this.
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Interesting matter
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I wonder ' I am alive!'
:SP:
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Thanks for the post.
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This post will help us to know about pollution
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Most of the people of our country are not aware of these problems..... Thanks for such informative post....
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nice one...
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Thanks for sharing
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its a nice post.......