Aquatic Ecosystems PYQs — 10 UPSC CSE Previous Year Questions

Question 1

Which of the following best explain(s) the rationale for protecting mangrove ecosystems in the context of climate resilience? Mangroves reduce tidal energy and store freshwater, making them ideal sites for paddy cultivation in saline estuarine belts. Their salt-sensitive roots filter seawater, making mangroves key to converting coastal land into freshwater aquaculture zones. By withstanding tidal surges and offering biomass resources, mangroves function both as natural bio-shields and livelihood bases for rural communities. Select the answer using the code given below :

Accepted Answer

D. 3 only

Question 2

Consider the following pairs: Wetland/Lake Location 1. Hokera Wetland Punjab 2. Renuka Wetland Himachal Pradesh 3. Rudrasagar Lake Tripura 4. Sasthamkotta Lake Tamil Nadu How many pairs given above are correctly matched ?

Accepted Answer

B. Only two pairs

Question 3

"Biorock technology" is talked about in which one of the following situations ?

Accepted Answer

A. Restoration of damaged coral reefs

Question 4

Which of the following have coral reefs? Andaman and Nicobar Islands Gulf of Kachchh Gulf of Mannar Sunderbans Select the correct answer using the code given below.

Accepted Answer

A. 1, 2 and 3 only

Question 5

The 2004 Tsunami made people realize that mangroves can serve as a reliable safety hedge against coastal calamities. How do mangroves function as a safety hedge ?

Accepted Answer

D. The mangrove trees do not get uprooted by storms and tides because of their extensive roots

Question 6

Two important rivers - one with its source in Jharkhand (and known by a different name in Odisha), and another with its source in Odisha - merge at a place only a short distance from the coast of Bay of Bengal before flowing into the sea. This is an important site of wildlife and biodiversity and a protected area. Which one of the following could be this ?

Accepted Answer

A. Bhitarkanika

Question 7

In the context of ecosystem productivity, marine upwelling zones are important as they increase the marine productivity by bringing the decomposer microorganisms to the surface. nutrients to the surface. bottom-dwelling organisms to the surface. Which of the statements given above is/are correct ?

Accepted Answer

B. 2 only

Question 8

The largest coral reef in the world is found near the coast of which one of the following countries?

Accepted Answer

A. Australia

Question 9

Estuaries possess distinct blooms of excessive growth of a pigmented dinoflagellates. These blooms are called:

Accepted Answer

A. red tides

Question 10

Given below are two statements, one labelled as Assertion (A) and the other labelled as Reason (R):

Assertion (A): Mangroves are very specialised forest ecosystems of tropical and sub-tropical regions bordering certain sea coasts.
Reason (R): They stabilise the shoreline and act as bulwark against encroachments by the sea.

Accepted Answer

A. Both A and R are true and R is the correct Explanation of A

Wetland/Lake	Location
1. Hokera Wetland	Punjab
2. Renuka Wetland	Himachal Pradesh
3. Rudrasagar Lake	Tripura
4. Sasthamkotta Lake	Tamil Nadu