Environment and Disaster Management › Protected areas and habitats
हिन्दी — Read in HindiMarine and coastal ecosystems
Coasts and seas as ecosystems: mangroves, seagrass, estuaries and lagoons, coastal regulation and erosion, marine protected areas and the treaties for the high seas. Prelims has asked what blue carbon is and where India has coral reefs.
Foundation note: Coral reefs of India
UPSC has asked
- Prelims 2026: why mangroves matter for climate resilience
- Prelims 2016: The Economics of Ecosystems and Biodiversity (TEEB)
Showing 2 of 7 articles, those that changed from 1 to 30 June 2026.Show all
Coasts under pressure
Great Nicobar project
Copy link to Great Nicobar projectPrelims and Mains
The Great Nicobar project is a plan for an International Container Transshipment Port at Galathea Bay, a greenfield joint use airport, a township and a power plant on Great Nicobar Island.
- It covers 166.1 sq km of the 921 sq km island.
Two figures for the tribal reserve
| Government statement | Tribal reserve land in the project |
|---|---|
| 2023 | 7.11 sq km |
| 1 May 2026 | 84.1 sq km |
Why the island matters
- The island is a biodiversity hotspot and home to the Shompen, a particularly vulnerable tribal group.
- The giant leatherback turtle nests at Galathea Bay, whose wildlife sanctuary was denotified in 2021 to make way for the port.
- The island is seismically active and subsided in the 2004 earthquake.
- Island coasts are zoned under the Island Coastal Regulation Zone framework, in which category IA is the most restrictive.
What changed
12 Jun 2026
- The Zoological Survey of India chose four west coast sites to move coral and giant clam colonies from the port area, both Schedule I species.
- A Wildlife Institute of India survey found leatherback nests at Galathea Bay.
- The government now says 84.1 sq km of the project falls in tribal reserves, against its 2023 figure of 7.11 sq km.
The Indian Express, 12 Jun 2026: 4 sites on Nicobar west coast identified for coral translocation, says Zoological Survey of India (opens in a new tab) · Frontline, 8 Jun 2026: Great Nicobar's blueprint for 'development at any cost' (opens in a new tab)
Show history (1 other update)
7 Aug 2026newly added
- The Zoological Survey of India records a reef of 116 hectares with more than 100 species of reef building coral in Galathea Bay, while the 2023 coastal maps of the National Centre for Sustainable Coastal Management show no coral there.
- A site with coral reef falls in the most protected coastal category, where a port cannot be built.
- The submission that the bay is a lower category was central to the National Green Tribunal dismissing objections in February 2026.
Mains: a mapping decision, and not an environmental argument, settled what the project may legally do.
Sand mining at Thottappally
Copy link to Sand mining at ThottappallyPrelims and Mains
The Kollam to Alappuzha coast is dense black sand rich in ilmenite, monazite, rutile, zircon and sillimanite.
- The sand acts as a natural wall against erosion and keeps sea water out of the backwaters.
- The Thottappally spillway of 1954 and its estuary drain low lying Kuttanad, about 3 m below sea level, to the sea, and the estuary's fine grains stabilise the coast.
- Monazite in the sand is radioactive, so stockpiles in the open are a radiation source.
From dredging to lost paddy
Harbour dredging
Dredging for the harbour, 2010 to 2014
Estuary mining
Mining of the estuary sand expands after the 2018 flood
Barrier lost
The black sand wall between sea and backwater thins
Erosion and salt
The coast erodes and salt water intrudes
Paddy lost
About 3,000 hectares of Kuttanad paddy land became uncultivable between 2020 and 2023
What changed
7 Jun 2026New
- Estuary sand mining by Indian Rare Earths Limited and Kerala Minerals and Metals Limited, expanded after the 2018 flood, is eroding the coast.
- About 3,000 hectares of Kuttanad became uncultivable between 2020 and 2023 from salt water intrusion.
- A December 2025 Kerala High Court case on harm to paddy and nesting sea turtles led to an expert committee.
Mains: Dredging justified as harbour maintenance and disaster management has become mineral extraction that worsens erosion, salinity and radiation exposure; the government cites IIT Madras and Swaminathan Commission studies in its defence.
Frontline, 7 Jun 2026: Black sand, broken shores (opens in a new tab)
Also filed elsewhere
- India's deep sea mining programme · on Ocean, polar and earth science missions
India's deep sea mining programme explores the seabed for minerals under three International Seabed Authority contracts.