Today, the demand of water use worries many people in many areas in the world. More deaths are caused by lack of clean water than war. Without clean water, diseases are spread consequently in some countries, for example, nearly 5000 children die from diarrhea-related diseases throughout the world each day. Globally, water is far more enough, but only 3percent of the planet’s water is fresh which is also in the form of snow or ice. Therefore, only a small amount of water is ready for human use which is unfortunately distributed unequally in geography. On the other hand, pollution in some developing countries affects clean water supply.
To solve the problem, engineers have historically been the main force to come up with methods. One way is to divert the flow of water from the plenty area to the arid area such as in China, India, etc. However, it is not a long-term, widespread solution which will not be able to meet agriculture need and lead some political issues. Another way is to extracting the salt from seawater. This is not a fresh idea and has already been used in many regions like Saudi Arabia and Israel, but the cost of building desalination plants is very high which are not suitable for many poor countries. Some new technologies such as nano-osmosis and nanotubes will reduce the cost but it requires engineers to continue to work on it for general and extensive use. There are some other ways to get more clean water such as: technologies which are being used to improve recycling of wastewater and sewage treatment; some new ways to reduce water use especially in agricultural irrigation; small decentralized distillation units.
In a word, engineers are demanded to work on new efficient ways to get clean water.
2008年10月1日星期三
Summary for Provide access to clean water
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Generally, a rather comprehensive and clear summary of the need of clean water and some solutions devise to get more of it. Well done! However, some grammatical and sentence structure errors are quite clear. For instance, the word after "to" should be in the singular form. Also, you never add the reference at the end.
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