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Environment › Protected areas and habitats

Marine and coastal ecosystems

Coasts and seas as ecosystems: mangroves, coral reefs, 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.

UPSC has asked

  • Prelims 2026: why mangroves matter for climate resilience
  • Prelims 2018: coral reefs
  • Prelims 2016: The Economics of Ecosystems and Biodiversity (TEEB)
  • Prelims 2014: where India has coral reefs

Showing 7 of 7 subjects, those that changed from 1 July to 15 September 2026.Show all

National report on deep-sea fishery resources

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Prelims and Mains

Below the reach of the light the sea is still crowded, and India has now read its own deep water to say where that crowding is. The reading matters because the same banks and slopes that hold the fish are the ones a fleet could strip.

  • The mesopelagic zone, 200 to 1,000 m down, holds lanternfishes, deep-sea shrimps and squids.
  • The Ministry of Earth Sciences released a national report on deep-sea fishery resources, drawing on more than 400 cruises of the research vessel Sagar Sampada.
  • It flags Kollam Bank, Angria Bank, the Mangalore slope, the Thiruvananthapuram terrace, Lakshadweep and the Andaman and Nicobar Islands as vulnerable areas.

What changed

  1. 20 Aug 2026

    PIB, 20 Aug 2026: National report on deep-sea fishery resources and marine hotspots (opens in a new tab)

Marine fish stock accounts

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Prelims and Mains

The report says where the fish are and what a fleet could take from them, but not what that taking would cost. The statistics ministry is now working out how to put the answer in the national accounts.

  • Natural Capital Accounting records natural assets and their depletion, which gross domestic product (GDP) misses.
  • The Ministry of Statistics and Programme Implementation (MoSPI) set out how it would build such accounts for India's marine fish stocks.
  • MoSPI is testing them under the United Nations System of Environmental-Economic Accounting.
  1. Judge the stock

    Compare current landings with ten years of landing data

  2. Resource rent

    Income left after labour, costs, depreciation and a normal return on vessels

  3. Discount

    Future rents brought to present value at a 2% real rate

  4. Asset account

    Shows whether the stock is maintained, depleted or regenerating

MoSPI's proposed method for marine fish stocks, from The Hindu, 31 August 2026

What changed

  1. 31 Aug 2026

    The Hindu, 31 Aug 2026: India's plan to begin natural-capital and climate-risk accounting of its blue economy | Explained (opens in a new tab)

  2. 6 Jul 2026Updatealso in news

    • The government says 91.1 per cent of 135 fish stocks assessed in 2022 were sustainable. The Food and Agriculture Organization is more cautious, and critics note that the assessment relies on landing data rather than surveys at sea, and that trawling damages the seabed on India's narrow continental shelf.

    The Hindu, 6 Jul 2026: The real crisis in India's fisheries (opens in a new tab)

Prelims and Mains

The project on the 921 sq km Great Nicobar Island comprises a transshipment port at Galathea Bay, a greenfield airport, a power plant and a township. The island is a biodiversity hotspot and is seismically active, having 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

  1. 7 Aug 2026Updatenewly added

    • Minutes of the project's biodiversity committee identify four sites on the west coast for moving giant clams and coral colonies out of Galathea Bay, a condition of the port's coastal clearance.
    • The Zoological Survey of India records a reef of 116 hectares with more than 100 species of reef building coral in the bay, while the coastal maps published in 2023 by 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.

    Frontline, 7 Aug 2026: The coastal zone maps that cleared the Great Nicobar port show Galathea Bay as free of corals, while the Zoological Survey of India is planning to translocate the corals that are there. (opens in a new tab)

  2. 7 Jul 2026New subject

    • Clearance has been sought for a fortified lighthouse, a convention centre and a museum at Indira Point, India's southernmost point, which lies just south of Galathea Bay.
    • The site falls in Island Coastal Regulation Zone IA and IVA. Category IA permits almost no construction, with narrow exceptions such as defence and public utilities after a detailed impact assessment.

    Mains: a series of individually small clearances adds up to a large ecological change on one stretch of coast.

    The Indian Express, 7 Jul 2026: Construction proposed at Indira Point, India's southernmost point, in the strictest island coastal zone category (opens in a new tab)

Prelims

Kalpasar is a proposed dam across the Gulf of Khambhat in Gujarat that would turn part of the gulf into a coastal freshwater reservoir for Saurashtra, with renewable generation and a road and rail corridor on the dam.

What changed

  1. 27 Jul 2026New subjectalso in news

    • The detailed project report for a dam across the Gulf of Khambhat in Gujarat, which would create a coastal freshwater reservoir for Saurashtra, is nearing completion with Dutch technical help. About 2,470 MW of hybrid renewable capacity and a road and rail corridor over the dam are planned. Salinity ingress and the loss of tidal flats are the ecological questions.

    PIB, 27 Jul 2026: SOCIO-ECONOMIC IMPACT AND TECHNICAL PROGRESS OF THE KALPASAR PROJECT (opens in a new tab)

Mangroves

Prelims and Mains

Mangrove roots slow waves and trap sediment, which is why a mangrove belt is counted as coastal defence rather than only as forest, and why a national programme now pays to put it back.

  • MISHTI (Mangrove Initiative for Shoreline Habitats & Tangible Incomes) was launched on World Environment Day 2023.
  • It aims to restore about 540 sq km of mangroves.
  • Gujarat was reported close to its MISHTI target at a review in Bhuj in September 2026.
  • A Mangrove GIS (MGIS) Portal was launched at that workshop to monitor the State's mangroves.
  • The Environment Minister released mangrove publications at the workshop and reviewed plantation work in Kachchh the next day.
  • Guneri in Kachchh, Gujarat's first Biodiversity Heritage Site, holds rare mangroves that grow inland, away from the sea.

What changed

  1. 14 Sep 2026

    PIB, 14 Sep 2026: Union Environment Minister visits Great Indian Bustard Habitat in Kachchh, Gujarat; Inaugurates GIB Soft Release Centre, Sayara Van Kavach and reviews Mangrove Plantation Efforts (opens in a new tab)

  2. 13 Sep 2026

    PIB, 13 Sep 2026: Union Environment Minister presides over Workshop on Mangrove Conservation in Bhuj; Releases Key Mangrove Publications and Reviews MISHTI Progress (opens in a new tab)

  3. 10 Jul 2026Update

    • The governing body of the National Compensatory Afforestation Fund Management and Planning Authority (CAMPA) extended the Mangrove Initiative for Shoreline Habitats and Tangible Incomes by three years to 2029 and raised its outlay to ₹600 crore, moving it to a landscape based approach to coastal restoration.

    PIB, 10 Jul 2026: Four new Wildlife and Forestry Conservation Projects for Dolphins, Snow Leopards, Wild Water Buffalo and Indian Rhinoceros approved by GB CAMPA (opens in a new tab)

Prelims and Mains

A forest nobody buys from enters a planning decision only once someone works out what it is worth, and the Total Economic Value of this one in Tamil Nadu has now been worked out.

  • A study put the Total Economic Value of the Pichavaram mangroves at ₹2,485.38 crore.
  • Blue carbon sits in the standing wood and in the waterlogged sediment below, where a lack of oxygen keeps it from rotting away.
  • Mangrove soil therefore holds its carbon only as long as it stays wet and undug.
  • Sediments76%

  • Vegetation24%

Share of carbon stored per hectare at Pichavaram, calculated from the tonnes reported in The Hindu, 3 September 2026

What changed

  1. 3 Sep 2026

    The Hindu, 3 Sep 2026: How valuable are mangroves? Study on Pichavaram ecosystem pegs it at ₹2,485.38 crore (opens in a new tab)

UPSC has asked

  • Prelims 2021: what blue carbon is

Mangroves of the Sundarbans

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Prelims and Mains

West Bengal holds the largest share of India's mangrove cover, almost all of it in the Sundarbans, where the forest is under pressure from conversion to fish ponds known locally as bheries.

What changed

  1. 25 Jul 2026New subjectalso in news

    • A survey of ten locations found more than 600 hectares of Sundarbans mangrove converted into shallow fish ponds called bheries, cleared from inside so that the forest still looks dense from the water. West Bengal holds 42.45 per cent of India's mangrove cover, about 2,119 sq km.

    The Hindu, 25 Jul 2026: Will restore mangroves lost to encroachments: Minister (opens in a new tab)

Also filed elsewhere