The speed of urbanization, industrialization and fast plus the population explosion of increasingly heavy pressure for the existing water resources. Water supplies in many municipalities, industrial increasingly contaminated by waste water, waste gas and waste in production operations. Amount of waste water of textile industry, paper industry contains cyanide (CN-) pass to 84 times, H2S exceed 4.2 times, concentrations of NH3 exceeded 84 times the standard should have the heavily polluting the surface water sources in the region.In agriculture the abuse of plant protection drugs make the source of water in rivers, lakes, canals and ditches is polluted, affecting water environment and human health. The massively aquaculture, using too many chemicals, lack of planning, does not comply with the technical process should have caused many negative effects to the environment.In large cities, the increase in population has caused a large amount of waste substances and this also is a major explanation for the water pollution. The population too crowded accompanied by lack of water treatment system waste makes the waste directly poured out rivers, lakes or canals, and that is the reason why the water source becoming contaminated
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