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Natural Resources — Science STD 9 — Question

Gujarat BoardEnglish MediumSTD 9ScienceNatural Resources3 Marks
Question

List main sources of water pollution.

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Answer

Main sources of water pollution are:

  • Waste from farms i.e. fertilizers and pesticides. The chemicals in them pollute the water.
  • Industries release their waste products directly into the rivers thus degrading water quality. Industries also contribute to thermal pollution as the coolants discharged by them causes a change in the average temperature of water, thereby degrading the water quality.
  • Disease causing agents like bacteria, viruses and protozoans enter the sewage system. This sewage is ultimately discharged into water bodies like sea.

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