Class 12th Biology 2014 Set2 Delhi Board Paper Solution
Question 1
State the cause of accelerated eutrophication.
Answer
Accelerated eutrophication:
It is the ageing of a water body due to nutrient enrichment of its water. It can be natural or artificial. Eutrophication takes thousands of years, but due to human activities the process has been accelerated. So, it is called accelerated eutrophication.
Causes of accelerated eutrophication:
1) Release of nutrient-rich sewage and industrial effluents lead to the introduction of nutrients such as nitrogen and phosphorus.
2) Sewage and industrial effluents also lead to increase in temperature and BOD of the water body, causing increased biological activity, thereby leading to algal blooms.
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