In modern industrial society, to ensure that the life of each person, each year must unearth 25 kinds of minerals in the ground. Oil resources, if they continue to be exploited at a rate as in the 90s of last century, it will be exhausted until 2016. Coal resources in the world is only 1500 years are still available, and estimates 12 Other natural resources just to maintain the same 50 years. The most serious of which is to mention the problem of freshwater shortage. At the beginning of XXI century, a number of South Asia, Central America, especially North Africa, East Africa, West Africa has emerged shortage of fresh water altogether.
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