Question 46 from UPSC CSE 2018 - Geography

Question

Consider the following statements:
1. Most of the world's coral reefs are in tropical waters.
2. More than one-third of the world's coral reefs are located in the territories of Australia, Indonesia, and Philippines.
3. Coral reefs host far more number of animal phyla than those hosted by tropical rainforests.
Which of the statements given above is/are correct?

Accepted Answer

Correct Option: D. 1, 2, and 3

Strategy: - Focus on global distribution patterns and biodiversity keywords.
- Statement 1: Corals thrive in warm tropical waters (standard knowledge).
- Statement 2: Australia, Indonesia, and the Philippines host the world's largest reef systems, holding over one-third of global reefs.
- Statement 3: Coral reefs are exceptionally rich in animal phyla, surpassing tropical rainforests.
- All three statements align with core ecological facts, validating the option.

Key Info: ## Coral Reefs Overview
Marine ecosystems predominantly found in shallow, tropical ocean waters, typically between 30°N and 30°S latitudes. Physical requirements include warm temperatures (23-29°C), clear waters, high light, and stable salinity. Major regions include the Indo-Pacific, Red Sea, and Caribbean.

Australia hosts the Great Barrier Reef--the largest reef system globally--while Indonesia features the Coral Triangle, and the Philippines has extensive coastal reefs. Together, these countries hold over one-third of the world's total reef area.

## Biodiversity
Coral reefs are often called 'rainforests of the sea' due to their extraordinary biological diversity. Of the estimated 34 recognized animal phyla, coral reefs contain at least 32, far exceeding tropical rainforests, which contain only about 9 animal phyla. This includes representatives of sponges (Porifera), cnidarians, mollusks, crustaceans, echinoderms, and countless fishes, making reefs a global biodiversity hotspot.

## Ecological Role
Reefs support fisheries, provide coastal protection, and are vital for marine species' lifecycles. They are threatened by climate change, ocean acidification, pollution, and destructive fishing practices.

## References
*   UNEP World Conservation Monitoring Centre
*   IUCN
*   National Oceanic and Atmospheric Administration (NOAA)
*   Primary peer-reviewed studies on coral reef biogeography and biodiversity

Answer

Option A: 1 and 2 only

Answer

Option B: 3 only

Answer

Option C: 1 and 3 only