UPSC Issue at a Glance | Mangroves in focus: Understanding significance, threats and conservation

(Relevance: UPSC Syllabus General Studies-II, III: Conservation, environmental pollution and degradation, environmental impact assessment, Government policies and interventions for development. 

UPSC has previously asked questions on mangroves not only in prelims but also in Mains, thus covering this topic from a broader perspective becomes essential.)

Question 1: What are mangroves and where are they found in India?

Mangroves are salt-tolerant trees and shrubs typical of estuarine and intertidal regions, meaning they grow in areas where freshwater and saltwater meet. Mangroves typically have aerial, breathing roots and waxy, succulent leaves, and are flowering plants. They thrive in high-rainfall areas (1,000–3,000 mm) with temperatures ranging from 26°C to 35°C. 

The unique characteristic of mangroves is the way their seeds/propagules germinate. The seeds actually germinate on the tree itself, and then fall of from the tree into the water, taking root only when encumbered by mud and sediment. This is very unique adaptation in the mangroves that helps them perpetuate in the harsh saline conditions. This phenomenon is scientifically termed vivipary.

Red mangrove, avicennia marina, grey mangrove, rhizophora etc., are some common mangrove trees. Abundant in swampy and marshy areas, mangroves represent a littoral forest ecosystem, which means they thrive in saline or brackish waters in coastal regions.

Mangroves in India

Mangroves are distributed in 123 nations and territories mostly in the tropics and subtropics. As per the Indian State of Forest Report (ISFR) 2023, India’s mangrove cover is around 4,992 sq. km, constituting 0.15% of the country’s total geographical area. West Bengal has the largest mangrove cover in India. Gujarat comes second with an estimated area of 1,177 sq km, with mangrove forests largely located in Gulf of Kutch and Gulf of Khambhat. With an estimated mangrove forests spread over 794 sq km, Kutch district has the largest mangrove area in Gujarat. Mangrove ecosystems are also found in Andhra Pradesh (Godavari-Krishna delta), Kerala, and the Andaman Islands. 

The Sundarbans (spread across India and Bangladesh) is the largest contiguous mangrove forest in the world, while Bhitarkanika is the second largest in India. The Sundarbans National Park is a UNESCO world heritage site and is famous for the Royal Bengal tigers, Gangetic dolphins, and other flora and fauna. Bhitarkanika is renowned for its vulnerable Olive Ridley turtles and salt-water crocodiles.

Question 2: What are the multifaceted significance of mangroves?

“Mangroves are rare, spectacular and prolific ecosystems on the boundary between land and sea. These extra ordinary ecosystems contribute to the wellbeing, food security, and protection of coastal communities worldwide.”- UNESCO

Mangrove are of profound ecological and economic significance, benefiting in multiple ways, such as:

1. Natural coastal defense (Bio-shields): Mangroves act as natural coastal guards and protectors. They are also referred to as ‘bio-shields’ as they mitigate the impact of strong waves and winds while guarding against coastal and soil erosion, primarily because of their roots.

2. Carbon sinks: Mangroves act as essential carbon sinks (absorb more carbon than they release) and are helpful in mitigating global warming. According to UNESCO, “One hectare of mangrove can store 3,754 tons of carbon it’s the equivalent of taking 2,650+ cars off the road for one year.”

Mangrove trees absorb carbon from the atmosphere and deposit it in the soil, where the carbon can remain for thousands of years if undisturbed. Mangroves behave differently from other trees that also remove CO2 as part of the photosynthesis process — the latter store the carbon in their branches and roots but, when the tree dies, the carbon is released back into the air. Mangroves, on the other hand, transfer the carbon to the soil, where it stays unaffected even if the tree is destroyed.

3. Economical Significance: Since mangroves are found in coastal regions, they are also a source of livelihood for coastal communities. Fisherwomen and farmers depend on the wide variety of ecological wealth mangroves offer. Fish farming, non-timber forest produce, honey collection, and boating are some local occupations on which locals depend. Additionally, different varieties of fish, shrimps, prawns, and plants thrive in mangrove forests supporting the blue economy.

Mangroves offer recreational tourism opportunities and these must be pursued sustainably. (Credit: Swasti Pachauri)

4. Supports biodiversity: These mangroves are rich in biodiversity. They support complex communities, where thousands of other species interact. They provide a valuable nursery habitat for fish and crustaceans; a food source for monkeys, deer, birds, even kangaroos; and a source of nectar for honeybees.

Question 3: What are the threats faced by mangrove forests in India? 

More than half of the world’s mangrove ecosystems are at risk of collapse, with nearly one in five facing severe risk, according to the findings of the first global mangrove assessment.

According to UNESCO, despite the multifaceted significance of Mangroves, they are disappearing three to five times faster than overall global forest losses, with serious ecological and socio-economic impacts. Current estimates indicate that mangrove coverage has been divided by two in the past 40 years.

Global warming and sea-level rise may lead to increased submergence of the mangroves and studies have shown that mangroves are pushed towards land due to sea-level rise over the period of time. However, landward movement is limited by human settlements and other industrial activities. Therefore, mangroves may be squeezed to a level where their conservation and restoration may not be possible.

Notably, climate change threatens one-third (33 per cent) of the mangrove ecosystems, according to the study done using the International Union for Conservation of Nature’s (IUCN) Red List of Ecosystems — a global standard for measuring the health of ecosystems.

The assessment finds that maintaining mangrove ecosystems across the globe will be key for mitigating the impacts of climate change, with healthy mangroves able to better cope with sea level rise and offering inland protection from the impacts of hurricanes, typhoons and cyclones.

Question 4: What steps have been taken for mangrove conservation?

Mangroves face immense threats from rampant urbanisation, depletion of coastal land systems because of agriculture, shrimp farming, and other dangers from rising sea temperatures. Unsustainable tourism practices also affect these vulnerable ecosystems.

However, increasingly, the protection of mangroves as a strategy for climate change-orientated action is also gaining popularity. In India, various initiatives and schemes have been launched for the conservation of mangroves, such as the MISHTI (Mangrove Initiative for Shoreline Habitats & Tangible Incomes), Amrit Dharohar, West Bengal’s Sustainable Aquaculture In Mangrove Ecosystem (SAIME), Andhra Pradesh’s Vana Samrakshana Samitis, and the Green Tamil Nadu Mission. Various initiatives also have been taken on a global level.

Mangrove Conservation Initiatives at National and Global Levels

📍MISHTI scheme: ‘Mangrove Initiative for Shoreline Habitats & Tangible Incomes (MISHTI)’ was announced in the Union Budget 2023-24 to promote and conserve mangroves as unique, natural eco-system having very high biological productivity and carbon sequestration potential, besides working as a bio shield. It was launched by Ministry of Environment, Forest & Climate Change on 5th June 2023.