A mangrove is a tiny tree or shrub that grows along coastlines, taking root in saline soil, typically underwater. The term "mangrove" refers to both the environment as a whole and the trees and shrubs that grow in the mangrove forest. Mangrove forests act as a natural barrier against storm surges, currents, waves, and tides. This article will explain to you about the Mangroves which will be helpful in Environment preparation for the UPSC Civil Service Exam.

What are Mangroves?

• Mangroves are a type of littoral plant formation found along tropical and subtropical sheltered coastlines.
• Mangroves are trees and bushes that grow beneath the high water levels of spring tides and have a remarkable capacity for salt water tolerance.
• Mangroves are salt-resistant and heat-resistant plant groups found in tropical and subtropical intertidal zones around the world.
• High rainfall (1,000 to 3,000 mm) and temperatures (varying from 26°C to 35°C) define such places.
• Mangrove species, especially mangrove forests in India, have a variety of adaptations in their morphology, anatomy, and physiology to enable them to live in wet soils, high salinity, storms, and tide surges.
• Mangrove forests can only be found around the equator in tropical and subtropical latitudes.
• Mangrove Forest trees produce a variety of roots:
  • Prop roots which are down into the water.
  • Air roots which are vertically structured up from the mud.
  • Stilt roots, also known as adventitious roots, grow from the tree's main trunk.
• Mangroves are classified as follows:
  • Red - Found on the coastlines.
  • Black - The dark bark of such mangrove trees is a distinguishing feature. They have more oxygen.
  • White mangroves grow at the highest elevation when compared to Red and Black mangroves.
• Mangroves are key habitats for coastal biodiversity. Many marine species, including shrimp, crabs, and fish, use mangroves as nursery habitat.
• They are also important in coastal erosion mitigation and storm damage reduction.
• Mangroves serve as bio-shields, protecting against harsh weather occurrences such as floods.
• Many people, mainly in rural areas, rely on mangrove ecosystems for a variety of biomass-based occupations.

Characteristics of Mangroves

• Mangroves are part of the Littoral Forest ecosystem.
• Mangroves are found primarily between the latitudes of 25° N and 25° S in the tropics and subtropics all over the world.
• Mangroves have a complicated salt filtering system and a complex root system.
• Mangrove forest trees typically grow to be 8-20 meters tall.
• Mangroves have special roots called breathing roots or pneumatophores that collect oxygen from the atmosphere.
• Because the oxygen content in the soil is low in the mangrove habitat, the root system absorbs oxygen from the atmosphere.
• Mangroves survive in hostile conditions such as excessive salt, muddy water, low oxygen levels, high temperature and high water tides
• Mangrove Forest have viviparity mode of reproduction meaning tree seeds germinate within the tree before falling.
• Mangroves are highly productive ecosystems. They are usually evergreen woods that thrive in tropical and subtropical climate, sheltered low lying beaches, estuaries, mudflats, tidal creeks, backwaters, marshes, and lagoons.
• Avicennia officinalis, Rhizophora mucronata, Sonneratia alba, Avicennia alba, Bruguiera cylindrica, Heritiera littoralis, Phoenix paludosa, and Morinda citrifolia are all important species of mangrove forest in India.

*For detailed notes of this topic, check this link Characteristics of Mangroves

Mangroves in India

• As per ISFR 2021 report, the mangrove cover in India is 4,992 sq km, which is 0.15% of the country’s total geographical area.
• Odisha and Maharashtra have seen significant increases in mangrove cover.
• The deltas of the Ganges, Mahanadi, Krishna and Godavari and kaveri river contain mangrove forest.
• Top 5 states with the most mangrove forest cover in India are:
• West Bengal: 2,114 sq km
• Gujarat: 1,175 sq km
• Andaman and Nicobar Islands: 616 sq km
• Andhra Pradesh: 405 sq km
• Maharashtra: 324 sq km
• Odisha: 259 sq km
• Indian mangroves consist of 46 species belonging to 22 genres.

• The Sundarbans mangroves are the world's largest single block of tidal holophytic mangroves.
• Herritiera fames, Rhizophora spp., Bruguiera spp., Ceriops decandra, Sonneratia spp., and Avicennia spp. are among the major species found in this dense mangrove forest. Nypa fruticans can be found along the creeks.
• The Royal Bengal Tiger and crocodiles can be found in this mangrove forest. Mangrove forests are being destroyed to make way for agricultural land.
• Bhitarkanika mangroves (Orissa), the second largest in the Indian subcontinent, have a high concentration of typical mangrove species as well as high genetic diversity.
• Mangrove swamps abound in the intertidal mudflats on both sides of the creeks in Andhra Pradesh's Godavari-Krishna deltaic regions.
• The construction of aquaculture ponds and salt pans has primarily degraded the mangroves of Pichavaram and Vedaranyam.
• Mangroves, mostly scrubby and degraded, occur along the intertidal region of estuaries and creeks in Maharashtra, Goa, and Karnataka on India's west coast.
• The mangrove vegetation in Kerala's coastal zone is sparse and thin.
• Mangroves Avicennia marine, Avicennia officinalis, and Rhizophora mucronata are found primarily in the Gulf of Kachchh and the Kori creek in Gujarat (northwest coast).
• Scrubby mangroves with stunted growth form narrow, discontinuous patches on soft clayey mud.
• The condition of the mangroves is improving, particularly in the Kori creek region, which is an Indus river paleodelta.
• Mangroves range in size from bushy stands of dwarf mangroves in the Gulf of Kuchchh to taller stands in the Sunderbans.
• The small tidal estuaries, neritic inlets, and lagoons of the Andaman and Nicobar Islands support a dense and diverse undisturbed mangrove flora.

Mangroves in World

• According to the Global Forest Resource Assessment 2020 (FRA 2020), 113 countries worldwide include Mangrove forests covering an estimated 14.79 million hectares.
• Asia has the largest mangroves areas followed by Africa, North and Central America, and South America.
• Oceania has the smallest amount of mangroves.
• More than 40% of the total area of mangroves was found to be in only four countries: Indonesia (19%), Brazil (9%), Nigeria (7%), and Mexico (6%).

Role of Mangroves

• Mangrove plants have (additional) special roots such as prop roots and pneumatophores that help to obstruct water flow and thus enhance sediment deposition in areas (where it already occurs), stabilise coastal shores, and provide a breeding ground for fishes.
• Mangroves prevent coastal soil erosion.
• Mangroves are home to a diverse range of vegetation, avifauna, and wildlife.
• Mangroves are environmentally essential because they serve as a reservoir in the tertiary waste assimilation process.
• Mangroves have an important function in supporting land accretion, mud bank stabilization, and wind, tidal, and wave energy dissipation.
• Mangroves improve water quality by absorbing nutrients that would otherwise generate toxic algal blooms offshore.
• Mangrove trees help to stabilize the coastline and reduce erosion caused by storm surges, currents, waves, and tides. They defend coastal areas against tsunamis, hurricanes, and flooding.
• Mangroves serve as breeding habitats for a variety of fish and protection for a diverse range of animals, including birds, invertebrates, mammals, and plants.
• Mangroves promote natural nutrient recycling.
• It provides locals with wood, firewood, medicinal plants, and edible plants.
• Mangroves provide a vital source of income for coastal populations who rely on honey, tannins, wax, and fishing.
• Mangroves help to decrease the inundation of coastal lowlands by reducing monsoonal tidal floods and also serve as significant carbon sinks.

*For detailed notes of this topic, check this link Role of Mangroves

Threat to Mangroves

• Biotic pressure and natural disasters have a significant negative impact on Mangrove ecosystems.
• Growing land acquisition for agriculture and industry along coasts, as well as the discharge of untreated domestic sewage and industrial effluents, and pesticide residues from agricultural lands, are threatening these forests.
• Upstream operations such as river training and natural erosion and accretion have an impact on the health of mangroves because the adequate ecological flow in rivers is required to flush silt and other pollutants from the mangroves.
• Climate change (rising sea levels) leads to the diverse extinction of mangrove ecosystems.
• Aquaculture - most of the mangrove cultivation is turned into shrimp farming which poses serious threats to the mangrove ecosystem.

Measures Taken to Protect Mangroves

• 1892: The Sundarbans is the world's first mangrove forest to be scientifically managed.
• 1976: The Environment Ministry set up The National Mangrove Committee.
• 1979: Recommended Mangrove mapping using remote sensing, land surveys, and other methods to identify degradation rate, analyzing sites for reserve forests, conservation programs and afforestation.
• 2005: The Mumbai High Court classified mangroves as forests.
• 2013: In the Sundarbans, the Biotechnology Department started an experimental bio-restoration initiative. It involves using native grasses to stabilize degraded mangrove stretches (salt-tolerant varieties).
• 2016: Over 15,000 hectares of mangroves have been declared as reserve forest by the Maharashtra government. Construction is prohibited within 50 m of these mangroves.
• 2018: The High Court ruled that the destruction of mangroves violated citizens' fundamental rights under Article 21 of the Constitution.
• 2018: The BOBLME (Bay of Bengal Large Marine Ecosystem) project brought together India and seven other Bay of Bengal region countries to safeguard mangroves. This project is led by the United Nations Food and Agriculture Organization and funded by GEF (Global Environment Facility).

Conclusion

Mangrove systems are rich in biodiversity and provide a number of ecological services. They also play a major role in protecting coastal areas from natural disasters thus conserving the environment. They are highly productive ecosystems that can export energy and materials to neighboring communities. They support a diverse heterotrophic food chain, serve as nurseries in some organisms' life cycles, and provide some protection against coastal erosion and storm surge attack. They are currently under severe anthropogenic pressures, as are many other types of wetland.

FAQs

Q1: What are mangroves?

Q2: Why are mangroves important for the environment?

Q3: What types of flora and fauna are commonly found in mangrove ecosystems?

Q4: How do mangroves contribute to local economies?

Q5: What are the major threats to mangrove ecosystems?

MCQs

1. Which of the following is a primary benefit of mangroves?

a) Reducing air pollution

b) Enhancing biodiversity

c) Increasing soil fertility

d) Producing freshwater

2. Which type of tree is commonly associated with mangrove ecosystems?

a) Pine

b) Oak

c) Rhizophora

d) Birch

3. What role do mangroves play in carbon sequestration?

a) They do not sequester carbon.

b) They store carbon in their leaves only.

c) They store carbon in both biomass and soil.

d) They release more carbon than they store.

4. Which of the following is a significant threat to mangrove ecosystems?

a) Overfishing

b) Deforestation for agriculture

c) Climate regulation

d) Aquaculture

5. Which of the following regions is known for its extensive mangrove forests?

a) Sahara Desert

b) Amazon Rainforest

c) Sundarbans

d) Himalayan Mountains

GS Mains Questions and Model Answers

Q1: Discuss the ecological significance of mangroves in coastal regions.

Answer: Mangroves are ecologically significant as they serve multiple roles in coastal regions. They provide essential habitat for a wide array of species, including fish, crustaceans, and birds, contributing to rich biodiversity. The intricate root systems of mangroves stabilize shorelines, preventing erosion and acting as natural barriers against storm surges and flooding, thereby protecting coastal communities. Furthermore, mangroves are vital for carbon sequestration, capturing and storing carbon dioxide from the atmosphere, which helps mitigate climate change. They also play a crucial role in maintaining water quality by filtering pollutants and excess nutrients, promoting healthier marine ecosystems. Overall, the ecological functions of mangroves are indispensable for sustaining both biodiversity and the livelihoods of coastal populations.

Q2: Analyze the socio-economic importance of mangroves for local communities.

Answer: Mangroves hold significant socio-economic importance for local communities, particularly those residing in coastal regions. They provide critical resources, including fish and shellfish, which are fundamental to the livelihoods of many fishermen. The sustainable harvest of timber and non-timber forest products from mangroves also supports local economies. Additionally, mangroves promote ecotourism, attracting visitors interested in their unique ecosystems and biodiversity, thereby creating job opportunities for local residents. Furthermore, the protective functions of mangroves against storms and erosion safeguard community assets and infrastructure, reducing economic losses during extreme weather events. Overall, mangroves contribute to food security, economic stability, and community resilience in coastal areas.

Q3: Evaluate the challenges faced in the conservation of mangrove ecosystems in India.

Answer: The conservation of mangrove ecosystems in India faces several challenges that undermine their sustainability. Deforestation for agriculture and urban development leads to significant habitat loss, diminishing the area of mangroves. Additionally, pollution from industrial discharges and agricultural runoff poses a severe threat to their health, affecting water quality and harming aquatic life. Climate change further exacerbates these challenges, with rising sea levels and increased storm intensity threatening the survival of mangrove forests. Inadequate awareness and participation of local communities in conservation efforts can hinder sustainable management practices. To address these challenges, it is essential to implement integrated coastal zone management strategies that promote conservation while balancing developmental needs. This includes community engagement, legal protection, and restoration initiatives to ensure the long-term viability of mangrove ecosystems.

Previous Year Questions on  Mangroves

1. UPSC CSE Prelims 2020

Question: Mangroves are primarily found in which of the following areas?

a) Desert regions

b) Freshwater lakes

c) Coastal regions

d) Mountain regions

Answer: c) Coastal regions

Explanation: Mangroves are primarily found in coastal regions, where they thrive in intertidal zones, providing habitat and ecological services.

2. UPSC CSE Mains 2018

Question: “Mangroves are critical to environmental sustainability.” Discuss this statement in the context of India’s coastal management policies. (200 words)

Answer: Mangroves are indeed critical to environmental sustainability, particularly in the context of India’s coastal management policies. These ecosystems provide invaluable services, including coastal protection, carbon sequestration, and habitat for diverse species. In India, where a significant portion of the population lives along the coast, the loss of mangroves can lead to increased vulnerability to climate change impacts, such as rising sea levels and intensified storms. Effective coastal management policies must prioritize the conservation and restoration of mangrove habitats, integrating them into broader strategies for sustainable development. This involves recognizing the ecological significance of mangroves in maintaining biodiversity and enhancing resilience against natural disasters. Additionally, policies should promote community participation in conservation efforts, ensuring that local populations are invested in the protection of these vital ecosystems. By incorporating mangrove conservation into national and state policies, India can enhance its environmental sustainability and safeguard the livelihoods of coastal communities.