Why in News?

A landmark ecological study has estimated the Total Economic Value (TEV) of Tamil Nadu's Pichavaram Mangrove Forest at Rs 2,485.38 crore, underscoring its immense but often overlooked role in ecological balance and climate regulation.

Key Findings of the Study

Capturing Non-Market Value

  • The ecosystem's worth translates to a remarkable Rs 1.83 crore per hectare
  • Effectively captures non-market ecological benefits frequently ignored in conventional development planning

Dominance of Sub-surface Carbon Sink

  • Soil organic carbon is the largest contributor to the TEV, accounting for nearly half of total value
  • Significantly exceeds carbon stored in above-ground vegetation
  • Mangrove sediments store 251.14 tonnes of carbon/ha compared to 79.45 tonnes/ha in above-ground vegetation
  • Highlights the need to conserve both mangrove cover and underlying sediments

Multi-Faceted Ecosystem Services

  • Carbon sequestration: Significant blue carbon sink
  • Coastal protection: Natural bio-shield buffering cyclones and saving disaster expenditure
  • Oxygen regulation: Replenishing atmospheric oxygen
  • Eco-tourism and recreation: Generating sustainable revenue, visitor value, and local livelihoods through boating and nature tourism

Nature-Based Solutions (NbS)

  • Functions as frontline natural shield for Disaster Risk Reduction (DRR)
  • Coastal stabilization
  • Ensures livelihood security for local coastal communities via sustainable provisioning services like fisheries

Global Conservation Context

  • 2024 IUCN Red List of Ecosystems warns that 50% of global mangrove ecosystems are at risk of collapse
  • This valuation comes at a critical time for conservation efforts

Way Forward for Policy Integration

  • Natural Capital Accounting
  • Green GDP frameworks
  • Payment for Ecosystem Services (PES)
  • Blue carbon financing mechanisms

Key Facts About Pichavaram Mangrove Forest

Geographical Location & Hydrography

  • Located in Cuddalore district of Tamil Nadu
  • Strategically situated between two prominent estuaries:
  • Vellar estuary (north)
  • Coleroon (Kollidam) estuary (south)
  • River systems along with the Uppanar river interconnect to form the Killai backwater complex

Geomorphology

  • Classified as an intertidal forested wetland
  • Complex labyrinth of roughly 4,400 large and small canals
  • Connects river mouths, the Killai backwaters, and the Bay of Bengal through a narrow littoral sandbar channel

Distinctive Feature: Permanent Submersion

  • Unlike many dry tidal flats, Pichavaram's mangrove trees are permanently rooted in shallow, brackish water

Flora

  • Dense network of:
  • Rhizophora apiculata (featuring prominent stilt roots)
  • Avicennia marina (characterized by pneumatophores or breathing roots)

Fauna

  • Vital nutrient-rich nursery for marine life
  • Commercial species: Tiger prawns and mud crabs
  • Notable avian species:
  • Spot-billed pelican
  • Spoon-billed sandpiper
  • White-bellied sea-eagle

Disaster Risk Reduction (Bio-Shield)

  • Functions as critical bio-shield
  • Buffer zone between land and sea
  • Holds and stabilizes shorelines
  • Retards coastal erosion
  • Aids climate change adaptation against extreme weather events

Global Recognition

  • Ramsar Wetland (designated 2022)
  • Important Bird and Biodiversity Area (IBA) by BirdLife International

Previous Year UPSC Questions

Prelims (2015)

Q: Which one of the following regions of India has a combination of mangrove forest, evergreen forest and deciduous forest?

  • (a) North Coastal Andhra Pradesh
  • (b) South-West Bengal
  • (c) Southern Saurashtra
  • (d) Andaman and Nicobar Islands

Answer: (d) Andaman and Nicobar Islands

Mains (2019)

Q: Discuss the causes of depletion of mangroves and explain their importance in maintaining coastal ecology.

Conservation Challenges & Way Forward

Major Threats to Mangroves

  • Habitat destruction for aquaculture and agriculture
  • Pollution from industrial and agricultural runoff
  • Sea-level rise due to climate change
  • Over-extraction of resources

Policy Recommendations

  1. Integration into Natural Capital Accounting systems
  2. Incorporation in Green GDP calculations
  3. Implementation of Payment for Ecosystem Services (PES)
  4. Access to blue carbon financing markets
  5. Community-led conservation initiatives
  6. Ecosystem-based management approaches