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Biodiversity, Conservation and Environmental Issues — BIOLOGY STD 12 Science — Question

Maharashtra BoardEnglish MediumSTD 12 ScienceBIOLOGYBiodiversity, Conservation and Environmental Issues5 Marks
Question
What are the two types of eutrophication? What is the main difference in them?
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Answer

  1. Natural Eutrophication and Cultural or Accelerated Eutrophication are two types of eutrophication.
  2. Natural eutrophication is caused due to natural processes. It is also called aging of a lake due to nutrient enrichment of water.
  3. It is a very slow and gradual process.
  4. Natural aging of lakes may take thousands of years, depending on the size of the lake, climatic conditions and other factors.
  5. Cultural or Accelerated eutrophication is caused due to human activities and chiefly due to pollution. Effluents from agricultural lands, industries and homes (household) cause such type of eutrophication.
  6. This phenomenon is called Cultural or Accelerated eutrophication.
  7. Due to excessive growth of algae there is lesser amount of dissolved oxygen for aquatic organisms, especially during night time. Due to this death of fish and other aquatic organisms take place.
  8. The dead bodies of aquatic organisms decompose causing further depletion of the dissolved oxygen.
  9. This results into complete collapse of the ecosystem of water body.

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