UPSC 2018 Environment & Ecology Previous Year Questions

Question 1

Why is a plant called Prosopis juliflora often mentioned in news?

Accepted Answer

Correct Option: B. Its extract is widely used in cosmetics. | It tends to reduce the biodiversity in the area in which it grows. | Its extract is used in the synthesis of pesticides. | None of the above. Prosopis juliflora is an invasive alien plant often mentioned because it can spread aggressively and reduce local biodiversity.

Question 2

Consider the following statements: 1. The Barren Island volcano is an active volcano located in the Indian territory. 2. Barren Island lies about 140 km east of Great Nicobar. 3. The last time the Barren Island volcano erupted was in 1991 and it has remained inactive since then. Which of the statements given above is/are correct?

Accepted Answer

Correct Option: A. 1 only | 2 and 3 | 3 only | 1 and 3. Barren Island is India's active volcano in the Andaman Sea. It is not east of Great Nicobar, and it erupted after 1991 as well, so only statement 1 is correct.

Question 3

With reference to the circumstances in Indian agriculture, the concept of "Conservation Agriculture" assumes significance. Which of the following fall under the Conservation Agriculture? 1. Avoiding the monoculture practices 2. Adopting minimum tillage 3. Avoiding the cultivation of plantation crops 4. Using crop residues to cover soil surface 5. Adopting spatial and temporal crop sequencing/crop rotations Select the correct answer using the code given below:

Accepted Answer

Correct Option: C. 1, 3 and 4 | 2, 3, 4 and 5 | 2, 4 and 5 | 1, 2, 3 and 5. Conservation agriculture emphasizes minimum soil disturbance, permanent soil cover with residues, and crop rotations/sequencing. Avoiding plantation crops is not a defining principle.

Question 4

Which of the following leaf modifications occur(s) in the desert areas to inhibit water loss? 1. Hard and waxy leaves 2. Tiny leaves 3. Thorns instead of leaves Select the correct answer using the code given below:

Accepted Answer

Correct Option: D. 2 and 3 only | 2 only | 3 only | 1, 2 and 3. Desert plants reduce transpiration through hard waxy leaves, very small leaves, and leaves modified into thorns/spines. All three are water-loss adaptations.

UPSC 2018 Environment & Ecology PYQs with Answers