With reference to Eutrophication, consider the following statements:
1. It occurs when excessive nutrients, primarily nitrogen and phosphorus, enter water bodies, stimulating excessive algal growth.
2. It leads to the formation of dead zones, where oxygen levels become too low to support marine life.
3. Natural eutrophication occurs over centuries, while cultural (human-induced) eutrophication happens rapidly due to human activities.

Which of the above statements are correct?
(a) 1 and 2 only
(b) 2 and 3 only
(c) 1 and 3 only
(d) 1, 2 and 3

Question

With reference to Eutrophication, consider the following statements:
1. It occurs when excessive nutrients, primarily nitrogen and phosphorus, enter water bodies, stimulating excessive algal growth.
2. It leads to the formation of dead zones, where oxygen levels become too low to support marine life.
3. Natural eutrophication occurs over centuries, while cultural (human-induced) eutrophication happens rapidly due to human activities.

Which of the above statements are correct?
(a) 1 and 2 only
(b) 2 and 3 only
(c) 1 and 3 only
(d) 1, 2 and 3

ONLiNE UPSC · Accepted Answer

Statement 1 is correct: Eutrophication occurs when excessive nutrients, mainly nitrogen and phosphorus, enter water bodies, leading to rapid algal growth (algal blooms). These nutrients come from fertilizers, sewage, and industrial runoff.

Statement 2 is correct: As algae decompose, they consume dissolved oxygen, leading to hypoxia (oxygen depletion). This creates dead zones, where oxygen levels become too low to support marine life, causing fish and other aquatic organisms to die.

Statement 3 is correct: Natural eutrophication is a slow process that takes place over centuries as lakes age and accumulate nutrients naturally. In contrast, cultural (human-induced) eutrophication occurs rapidly due to human activities like agriculture, urban runoff, and wastewater discharge

Eutrophication

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M Question 1	⏱ 0
With reference to Eutrophication, consider the following statements: 1. It occurs when excessive nutrients, primarily nitrogen and phosphorus, enter water bodies, stimulating excessive algal growth. 2. It leads to the formation of dead zones, where oxygen levels become too low to support marine life. 3. Natural eutrophication occurs over centuries, while cultural (human-induced) eutrophication happens rapidly due to human activities. Which of the above statements are correct? (a) 1 and 2 only (b) 2 and 3 only (c) 1 and 3 only (d) 1, 2 and 3