UPSC Prelims 2013 · CSAT
Question 40: Reading Comprehension
What is/are the characteristics of a water body with cultural eutrophication ?
- 1.Loss of ecosystem services
- 2.Loss of flora and fauna
- 3.Loss of mineral nutrients
Select the correct answer using the code given below :
AnswerUPSC’s answer is (b).
Cultural eutrophication follows excess nutrient input: the water turns turbid, large plants vanish, and in the worst cases oxygen runs out and fish die. The passage says important ecosystem services are lost, including the supply of wild-caught fish and recreation. So statements 1 (loss of services) and 2 (loss of plants and animals) hold. Statement 3 is reversed: the problem is a surplus of nutrients, not a loss of them.
- 1. Provisioning and cultural ecosystem services are lost.
- 2. Large plants are eliminated and fish die in the worst cases.
- 3. Nutrients are in excess, not lost.
How you could have got this
- If you were sure statement 2 is correct, (a) goes: it leaves 2 out.
What you needed to know: Large plants are eliminated and fish die in the worst cases.
- Then, if you were sure statement 3 is not correct, (c) and (d) go: each of them includes 3.
What you needed to know: Nutrients are in excess, not lost.
Only (b) is left. You didn’t need statement 1.
Which options go is worked out from UPSC’s key and the options, not by a model.
Why each option is right or wrong
- (a) Wrong. It leaves out the loss of plants and animals.
- (b) Right. Loss of ecosystem services and of flora and fauna both occur.
- (c) Wrong. Nutrients are in excess, not lost.
- (d) Wrong. It includes the reversed statement 3.
Answer: UPSC’s key. Explanation: written by UPSC Grade, not by UPSC.
Source: UPSC, Civil Services (Preliminary) Examination 2013, General Studies Paper II (CSAT), Series A. The paper on upsc.gov.in.