UPSC Prelims 2026Question 23Environment

Which of the following best explain(s) the rationale for protecting mangrove ecosystems in the context of climate resilience ?
1. Mangroves reduce tidal energy and store freshwater, making them ideal sites for paddy cultivation in saline estuarine belts.
2. Their salt-sensitive roots filter seawater, making mangroves key to converting coastal land into freshwater aquaculture zones.
3. By withstanding tidal surges and offering biomass resources, mangroves function both as natural bio-shields and livelihood bases for rural communities.
Select the answer using the code given below:

Options

(a)1 only
(b)1 and 2
(c)2 and 3
(d)3 only

Correct answer: d

Decision rule

A conservation rationale never converts the habitat to another use; the sound line pairs the ecosystem's protective function with the livelihoods it supports.

Explanation

Correct Answer

(d) 3 only

Explanation of the Correct Answer

The best rationale for protecting mangrove ecosystems in the context of climate resilience is given by statement 3 only.

Statement 1 is incorrect:
Mangroves do reduce tidal energy and help buffer coastal areas against storm surges, but they do not store freshwater in a way that makes them ideal sites for paddy cultivation. Mangroves grow in saline and brackish estuarine conditions. Converting mangrove areas into paddy fields damages coastal ecosystems and weakens climate resilience.
Statement 2 is incorrect:
Mangroves are adapted to saline conditions, but their roots are not simply “salt-sensitive roots” that filter seawater to convert coastal land into freshwater aquaculture zones. Mangroves have salt-exclusion, salt-excretion and salt-tolerance mechanisms. They are not meant to transform saline coastal land into freshwater aquaculture sites.
Statement 3 is correct:
Mangroves act as natural bio-shields by reducing the impact of tidal surges, cyclones, coastal erosion and wave energy. They also support rural livelihoods through fish, crabs, honey, fuelwood, fodder, tannins and other biomass-based resources when used sustainably.

Therefore, the correct answer is (d) 3 only.

Why Other Options Are Incorrect

Option	Verdict	Explanation
(a) 1 only	Incorrect	Statement 1 wrongly links mangroves with freshwater storage and ideal paddy cultivation in saline estuarine belts.
(b) 1 and 2	Incorrect	Both statements 1 and 2 are incorrect. Mangroves are not freshwater-conversion systems for paddy or aquaculture.
(c) 2 and 3	Incorrect	Statement 3 is correct, but statement 2 is incorrect because mangroves do not convert coastal land into freshwater aquaculture zones.
(d) 3 only	Correct	Mangroves provide coastal protection and support livelihoods, making them crucial for climate resilience.

Relevant Supplementary Information

Mangroves and Climate Resilience

Function of Mangroves	How It Helps Climate Resilience
Reduction of wave and tidal energy	Protects coastal settlements from storm surges and cyclones
Coastal erosion control	Roots bind sediments and stabilize shorelines
Carbon sequestration	Mangroves store large amounts of blue carbon in biomass and sediments
Nursery habitat	Supports fish, crabs, prawns and other marine life
Livelihood support	Provides fisheries, honey, fuelwood and other resources
Flood buffering	Slows water flow and reduces damage during extreme weather
Biodiversity conservation	Supports birds, reptiles, fish, molluscs and other species
Salinity tolerance	Allows survival in brackish and saline coastal zones

Mangrove Function	How It Works	Climate Resilience Value
Natural bio-shield	Dense roots and vegetation reduce wave and tidal energy	Protects coastal settlements from cyclones, storm surges and tidal floods
Coastal erosion control	Roots trap and bind sediments	Stabilizes shorelines and prevents land loss
Flood buffering	Mangrove belts slow down incoming water	Reduces intensity of coastal flooding
Blue carbon storage	Stores carbon in biomass and waterlogged sediments	Helps climate change mitigation
Biodiversity support	Provides habitat for fish, crabs, prawns, birds and reptiles	Maintains ecological balance and food chains
Nursery function	Juvenile fish and crustaceans grow in mangrove waters	Supports fisheries and coastal livelihoods
Livelihood support	Provides fish, crabs, honey, fuelwood and other biomass resources	Supports rural and coastal communities
Salinity adaptation	Mangroves tolerate saline and brackish water	Survive in harsh coastal environments where many plants cannot

Correcting Common Misconceptions about Mangroves

Misconception	Correct Understanding
Mangroves are ideal paddy cultivation areas	Incorrect. Converting mangroves to agriculture harms coastal resilience.
Mangroves store freshwater for farming	Incorrect. They survive in saline/brackish conditions but do not act as freshwater reservoirs.
Mangrove roots are salt-sensitive	Incorrect. Mangroves are salt-tolerant and have adaptations to handle salinity.
Mangroves convert seawater into freshwater aquaculture zones	Incorrect. They support brackish-water ecosystems, not freshwater conversion.
Mangroves are wastelands	Incorrect. They are highly productive coastal ecosystems.

Important Mangrove Adaptations

Adaptation	Meaning / Function
Pneumatophores	Breathing roots that help gas exchange in waterlogged soils
Stilt roots / prop roots	Provide support in soft, unstable coastal mud
Salt exclusion	Some mangroves prevent excess salt from entering roots
Salt excretion	Some species remove salt through leaves
Vivipary	Seeds germinate while still attached to the parent plant
Lenticels	Pores that help in gas exchange

Major Mangrove Areas in India

Mangrove Area	State / Region	Importance
Sundarbans	West Bengal	Largest mangrove forest in India; habitat of Royal Bengal Tiger
Bhitarkanika	Odisha	Rich mangrove biodiversity; crocodile habitat
Pichavaram	Tamil Nadu	Important mangrove wetland and coastal protection zone
Muthupet	Tamil Nadu	Important estuarine mangrove ecosystem
Godavari-Krishna mangroves	Andhra Pradesh	Important deltaic mangrove system
Gulf of Kachchh mangroves	Gujarat	Mangroves in arid coastal conditions
Andaman and Nicobar mangroves	Islands	Highly diverse island mangrove ecosystems

Mangrove Area	State / Region	Important Feature
Sundarbans	West Bengal	Largest mangrove forest in India; habitat of Royal Bengal Tiger
Bhitarkanika	Odisha	Important mangrove ecosystem; known for saltwater crocodiles
Pichavaram	Tamil Nadu	One of India’s important mangrove wetlands
Muthupet	Tamil Nadu	Important mangrove region in the Cauvery delta
Godavari-Krishna mangroves	Andhra Pradesh	Deltaic mangrove ecosystem
Gulf of Kachchh mangroves	Gujarat	Mangroves in arid/semi-arid coastal conditions
Mumbai mangroves	Maharashtra	Urban coastal protection and biodiversity value
Goa mangroves	Goa	Estuarine mangroves along rivers and backwaters
Andaman and Nicobar mangroves	Island region	Highly diverse island mangrove ecosystems

Key Takeaways from the Tables

Mangroves = natural bio-shields against cyclones, tidal surges and coastal erosion.
They are important blue carbon ecosystems.
They support rural livelihoods through fisheries, honey, crabs and other biomass resources.
Mangroves are salt-tolerant, not salt-sensitive.
They should not be converted into paddy fields or aquaculture zones.
The best answer is statement 3 only.

Point	Explanation
Mangroves are natural bio-shields	They reduce the impact of cyclones, storm surges, tidal waves and erosion.
Mangroves support livelihoods	Fisheries, crabs, honey and biomass resources support coastal communities.
Mangroves are blue carbon ecosystems	They store large amounts of carbon in biomass and sediments.
Mangroves are salt-tolerant, not freshwater-converting systems	They survive in saline conditions but do not convert seawater into freshwater.
Conversion is harmful	Turning mangroves into paddy fields or aquaculture zones weakens climate resilience.
Statement 3-type framing is correct	Mangroves protect coasts and support rural livelihoods, making them vital for climate resilience.

Context and Current Relevance

Mangroves are increasingly important due to rising risks of cyclones, sea-level rise, storm surges and coastal erosion.
India has launched initiatives such as MISHTI to promote mangrove conservation and restoration.
Protecting mangroves supports both climate adaptation and livelihood security for coastal communities.

Table: Correct and Incorrect Ideas about Mangroves

Statement / Idea	Correct or Incorrect	Explanation
Mangroves reduce tidal energy	Correct	They act as natural buffers against waves, tides and storm surges.
Mangroves store freshwater for paddy cultivation	Incorrect	Mangroves grow in saline/brackish zones; they are not freshwater storage systems.
Mangrove areas are ideal for paddy cultivation	Incorrect	Converting mangroves into paddy fields damages coastal protection and biodiversity.
Mangrove roots filter seawater into freshwater	Incorrect	Mangroves tolerate or regulate salt; they do not convert seawater into freshwater zones.
Mangroves support fisheries	Correct	They act as breeding and nursery grounds for fish, prawns and crabs.
Mangroves are natural bio-shields	Correct	They protect coasts from erosion, cyclones and storm surges.
Mangroves are wastelands	Incorrect	They are highly productive ecosystems with ecological and economic value.

Table: Mangrove Adaptations

Adaptation	Meaning	Purpose
Pneumatophores	Breathing roots growing above the soil	Help plants take oxygen in waterlogged conditions
Prop roots / stilt roots	Supporting roots emerging from trunk or branches	Provide stability in soft muddy soil
Salt exclusion	Roots prevent excess salt from entering the plant	Helps survival in saline conditions
Salt excretion	Leaves excrete excess salt	Helps regulate internal salt levels
Vivipary	Seeds germinate while still attached to parent plant	Helps seedlings survive in tidal environments
Waxy leaves	Thick leaves reduce water loss	Helps tolerate saline stress
Lenticels	Small pores on roots/stems	Aid gas exchange in oxygen-poor soils

Table: Mangroves vs Other Coastal Ecosystems

Feature	Mangroves	Coral Reefs	Seagrass Meadows
Location	Intertidal coastal and estuarine zones	Shallow tropical marine waters	Shallow coastal waters
Main climate role	Coastal protection and blue carbon storage	Wave energy reduction and biodiversity support	Carbon storage and marine habitat
Key adaptation	Salt tolerance and aerial roots	Calcium carbonate skeletons	Underwater flowering plants
Major biodiversity role	Nursery grounds for fish and crustaceans	Habitat for diverse marine species	Feeding grounds for dugongs and turtles
Threats	Conversion, pollution, coastal development	Bleaching, warming, acidification	Pollution, dredging, sedimentation
Livelihood link	Fisheries, honey, fuelwood, crabs	Fisheries and tourism	Fisheries and coastal productivity

Table: Threats to Mangrove Ecosystems

Threat	Impact on Mangroves
Aquaculture expansion	Converts mangrove areas into shrimp/fish farms
Agricultural conversion	Destroys natural mangrove cover
Urbanization	Leads to land reclamation and habitat fragmentation
Industrial pollution	Damages roots, water quality and biodiversity
Port and coastal infrastructure	Alters tidal flows and sediment movement
Over-extraction of biomass	Reduces forest density and regeneration
Sea-level rise	Can submerge mangrove areas if landward migration is blocked
Cyclones and extreme events	Can damage mangroves, though healthy mangroves also reduce cyclone impact

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