The Power of Mangroves Over Seawalls

Source: The Hindu

Context:

The landfall of Cyclone Dana near Bhitarkanika on the Odisha coast has put the spotlight on the powerful protective role of coastal mangroves against storm surges and cyclones, in contrast to expensive engineered seawalls and groynes. Indian coastal states have spent ₹2,641 crore over the last decade on hard engineered protection, even as the National Coastal Mission’s budget fell from ₹195 crore in 2022-23 to ₹50 crore in 2024-25. The editorial argues that India must shift toward Ecosystem-based Adaptation (EbA), using mangroves, seagrass meadows, and coral reefs as dynamic, self-sustaining buffers for the 11,000 km coastline and the 250 million people living near it.

India’s Coastal Vulnerability

• India’s coastline: about 11,000 km.
• Coastal population at risk: about 250 million people.
• Cyclone Dana made landfall near Bhitarkanika, Odisha, where mangroves played a clear shielding role.

Why Mangroves Work as Climate Shields?

• Dense aerial root networks break the energy of incoming waves, reducing storm surge damage.
• They trap organic sediment at the roots, helping coastlines build up against rising seas.
• They are “blue carbon” sinks, locking carbon at rates much higher than tropical rainforests.
• They are self-repairing and strengthen over time, unlike concrete seawalls that degrade.
• Research finds India is a global hotspot for coastal EbA, where mangroves protect more people per hectare than almost any other country.

Why Seawalls Are Not the Best Long-Term Answer?

• They are expensive to build and maintain.
• They degrade under repeated cyclone and tidal stress.
• They are rigid, while coastlines move.
• They can shift erosion downstream, harming neighbouring stretches.
• They do not provide any biodiversity, carbon, or livelihood co-benefits.

What is Ecosystem-based Adaptation (EbA)?

• EbA is a nature-centric climate strategy that uses biodiversity and ecosystem services to help communities adapt to climate change.
• It uses natural habitats like mangroves, seagrass meadows, coral reefs, salt marshes, wetlands, and forests as dynamic buffers against climate hazards.
• Unlike “grey” engineered infrastructure (concrete walls, groynes), EbA harnesses living ecosystems that adapt and self-sustain over time.
• Promoted by the Convention on Biological Diversity (CBD) and the United Nations Framework Convention on Climate Change (UNFCCC) as climate-adaptation best practice.

What are Mangroves and Where Are They Found in India?

• Mangroves are salt-tolerant trees and shrubs that grow in the intertidal zones along tropical and subtropical coasts.
• Their aerial and stilt roots trap sediment and break waves.
• They are rich biodiversity habitats, home to fish, crustaceans, reptiles, and birds.
• India’s major mangrove ecosystems include:
  • Sundarbans in West Bengal, the world’s largest mangrove forest, a UNESCO World Heritage Site.
  • Bhitarkanika in Odisha, known for saltwater crocodiles and Olive Ridley turtles.
  • Pichavaram and Muthupet in Tamil Nadu.
  • Coringa in Andhra Pradesh.
  • Mahanadi delta, Krishna delta, Godavari delta.
  • Gulf of Kutch and Gulf of Khambhat in Gujarat.
  • Andaman and Nicobar Islands.

What is Blue Carbon and Why Does It Matter?

• Blue carbon is carbon dioxide captured and stored by coastal and marine ecosystems like mangroves, seagrass meadows, salt marshes, and tidal flats.
• Per unit area, mangroves store more carbon than most terrestrial forests.
• Their soil in particular acts as a long-term carbon sink.
• Protecting and restoring these ecosystems thus delivers climate mitigation as well as adaptation.

What is the National Coastal Mission?

• A central scheme to protect and manage India’s coastal areas, including mangroves, coral reefs, biodiversity, and coastal communities.
• Comes under the Ministry of Environment, Forest and Climate Change (MoEFCC).
• Funds activities like mangrove restoration, coral reef protection, capacity building, awareness, and shoreline management.

Key Initiatives India Has Taken

• MISHTI Programme: Mangrove Initiative for Shoreline Habitats and Tangible Incomes, announced in the Union Budget 2023-24, for mangrove plantation along coastlines and salt-pan lands.
• Integrated Coastal Zone Management (ICZM) Project: World Bank-supported project for coastal zone management in selected states.
• Coastal Regulation Zone (CRZ) Notification: A regulatory framework for activities along the coast.
• National Action Plan on Climate Change (NAPCC) and its National Coastal Mission.

Practice MCQs

Q1. With reference to India’s coastal vulnerability and the case for mangroves, consider the following statements:

1. India’s coastline is about 11,000 km long.
2. Around 250 million people in India live in areas directly threatened by coastal climate hazards.
3. Indian coastal states spent about ₹2,641 crore on hard engineered protection over the last decade.
4. The National Coastal Mission’s budget fell from ₹195 crore in 2022-23 to ₹50 crore in 2024-25.

How many of the above statements are correct?

(a) Only one (b) Only two (c) Only three (d) All four (e) None

Q2. With reference to the role of mangroves as climate shields, consider the following statements:

1. Mangrove root networks break the energy of incoming waves and reduce storm surge damage.
2. Mangroves trap sediment and help coastlines build up against rising sea levels.
3. Mangrove ecosystems sequester carbon at rates many times higher than terrestrial tropical rainforests.
4. Mangrove ecosystems are rigid and degrade rapidly, requiring constant repair like concrete seawalls.

Which of the above are correct?

(a) 1, 2 and 3 only (b) 1, 3 and 4 only (c) 2 and 4 only (d) 1 and 4 only (e) All four

(Statement 4 is wrong; mangroves are self-repairing and grow stronger over time, unlike seawalls that degrade.)

Q3. With reference to India’s mangrove ecosystems, consider the following statements:

1. The Sundarbans, spread between India and Bangladesh, is the world’s largest mangrove forest and a UNESCO World Heritage Site.
2. Bhitarkanika in Odisha is known for saltwater crocodiles and Olive Ridley turtle nesting sites.
3. Pichavaram and Muthupet are notable mangrove ecosystems in Tamil Nadu.
4. India has no significant mangrove ecosystems on its west coast.

Which of the above are correct?

(a) 1, 2 and 3 only (b) 1, 3 and 4 only (c) 2 and 4 only (d) 1 and 4 only (e) All four

(Statement 4 is wrong; India has significant mangrove ecosystems on the west coast, especially in the Gulf of Kutch and Gulf of Khambhat in Gujarat.)

Q4. With reference to Ecosystem-based Adaptation (EbA) and related Indian initiatives, consider the following statements:

1. The MISHTI Programme stands for “Mangrove Initiative for Shoreline Habitats and Tangible Incomes”.
2. The Coastal Regulation Zone (CRZ) Notification is a regulatory framework to protect India’s coastal ecosystems.
3. The Integrated Coastal Zone Management (ICZM) Project is supported by the World Bank.
4. The National Coastal Mission is part of the National Action Plan on Climate Change (NAPCC).

How many of the above statements are correct?

(a) Only one (b) Only two (c) Only three (d) All four (e) None

Answer Key

1. (d), All four statements are correct.
2. (a), Statements 1, 2, 3 are correct; Statement 4 is wrong because mangroves are self-repairing and grow stronger over time.
3. (a), Statements 1, 2, 3 are correct; Statement 4 is wrong because India has significant mangrove ecosystems on its west coast.
4. (d), All four statements are correct.

Exam Relevance

Exam	Relevance
UPSC Prelims	GS Paper III on Environment, Biodiversity, Climate Change (Mangroves, EbA, Blue Carbon, CRZ)
UPSC Mains	GS Paper I on Geography; GS Paper III on Environment, Disaster Management, Climate Change
BPSC and State PCS	Environment, Geography, Disaster Management, Current Affairs
Banking and NABARD	General Awareness on environment
NABARD Grade A	Environment, rural sustainability, climate adaptation