13-12-2014, 04:50 AM
i want a ppt on water pollution in sanskrit language. please
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ppt in sanskrit language on water pollution
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i want a ppt on water pollution in sanskrit language. please
21-03-2017, 10:32 AM
Water pollution is the contamination of bodies of water (eg lakes, rivers, oceans, aquifers and groundwater). This form of environmental degradation occurs when pollutants are discharged directly or indirectly into bodies of water without adequate treatment to remove harmful compounds. Water pollution affects the entire biosphere - plants and organisms that live in these bodies of water. In almost all cases the effect damages not only individual species and populations, but also natural biological communities.
Water pollution is a major global problem requiring the ongoing evaluation and review of water resources policy at all levels (international to aquifers and individual wells). It has been suggested that water pollution is the leading cause of death and disease in the world, accounting for more than 14,000 deaths every day. It is estimated that 580 people die in India from diseases related to water pollution every day. About 90 percent of the water in China's cities is polluted. As of 2007, half a billion Chinese had no access to safe drinking water. In addition to the acute problems of water pollution in developing countries, developed countries also continue to struggle against pollution problems. For example, in the most recent national water quality report in the United States, 44 percent of assessed miles, 64 percent of assessed acres and 30 percent of assessed bays and estuarine miles were Classified as contaminated. The head of China's national development agency said in 2007 that a quarter of the length of China's seven major rivers were so poisoned that water damaged the skin. Water is typically referred to as contaminated when it is damaged by anthropogenic contaminants and does not support human use, such as drinking water, or experiences a marked change in its ability to support its constitutive biotic communities, such as fish. Natural phenomena such as volcanoes, algal blooms, storms and earthquakes also cause major changes in water quality and the ecological status of water.
Causes
Specific contaminants leading to contamination in water include a broad spectrum of chemicals, pathogens, and physical changes such as elevated temperature and discoloration. While many of the chemicals and controlled substances can be natural (calcium, sodium, iron, manganese, etc.), concentration is often the key to determining what is a natural component of water and what is a contaminant. High concentrations of natural substances can have negative impacts on aquatic flora and fauna. Substances that deplete oxygen can be natural materials such as vegetable matter (eg leaves and grass) as well as man-made chemicals. Other natural and anthropogenic substances can cause turbidity (cloudiness) that blocks light and disrupts plant growth, and obstructs the gills of some species of fish. Many of the chemicals are toxic. Pathogens can cause waterborne diseases in human or animal hosts. The alteration of the physical chemistry of water includes acidity (pH change), electrical conductivity, temperature and eutrophication. Eutrophication is an increase in the concentration of chemical nutrients in an ecosystem to an extent that increases the primary productivity of the ecosystem. Depending on the degree of eutrophication, subsequent negative environmental effects, such as anoxia (oxygen depletion) and severe reductions in water quality may occur, affecting fish and other animal populations.
Effects of water pollution
Some people believe that pollution is an inescapable result of human activity: they argue that if we want to have factories, cities, ships, cars, oil and coastal centers, there is almost certainly some degree of pollution. In other words, pollution is a necessary evil that people must endure if they want to progress. Fortunately, not everyone agrees with this view. One of the reasons why people have awakened to the problem of pollution is that it entails own costs that undermine the economic benefits of pollution.
Take oil spills, for example. They can happen if the tankers are too badly built to survive accidents at sea. However, the economic benefit of compromising the quality of the tanker brings an economic cost when an oil spill occurs. Oil can be washed on nearby beaches, devastate the ecosystem and seriously affect tourism. The main problem is that the people who bear the cost of the spill (typically a small coastal community) are not the people who caused the problem in the first place (the people who operate the tanker). However, without a doubt, anyone who puts gasoline in their car - or uses almost any type of oil - fueled transportation - contributes to the problem in some way. So oil spills are a problem for everyone, not just people living on the coast and the tanker operates.
Wastewater is another good example of how pollution can affect us all. Wastewater discharged into coastal waters can be washed off the beaches and cause a health risk. People who bathe or navigate in water can get sick if they swallow contaminated water, but sewage can also have other harmful effects: they can poison shellfish (such as cockles and mussels) growing near the shore. People who eat poisoned crustaceans suffer from an acute - and sometimes fatal - illness called paralytic seafood poisoning. Shellfish are no longer trapped along many coasts because they are simply too polluted with wastewater or toxic chemical wastes that have been discharged from nearby land.
Pollution is important because it damages the environment on which people depend. The environment is not something distant and separate from our lives. It is not a pretty coastline hundreds of miles from our homes or a wild landscape that we only see on television. The environment is everything that surrounds us and gives us life and health. Destroying the environment ultimately reduces the quality of our own lives-and that, more selfishly, is why pollution must matter to all of us.
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