UPSC Express

• Sunderbans is the largest single block mangrove forest in the world.
  

About: Sundarbans:

• Sundarbans is a mangrove area in the delta formed by the confluence of the Ganga, Brahmaputra and Meghna Rivers in the Bay of Bengal.
  
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• It is the largest single block mangrove forest in the world.
  
• The Sundarbans mangrove forest covers an area of about 10,000 sq. km, of which forests in Bangladeshextend over 6,017 sq. km and in India, they extend over 4,260 sq. km.
  
• About half a million people of India and Bangladesh are dependent on the Sundarbans for their livelihood.
  
• It is classified as a moist tropical forest dominated by “Sundri tree”.
  • It yields a hard wood, used for building houses and making boats, furniture and other things.
    
  
  
• It acts as shelter belt to protect the people fromstorms, cyclones, tidal surges, sea water seepageand intrusion.
  
• It is a UNESCO World Heritage Site.
  • A World Heritage Site is a landmark or area with legal protection by an international convention administered by the United Nations Educational, Scientific and Cultural Organization (UNESCO).
    
  
  
• It is the only mangrove reserve in the world inhabited by tigers.
  
• There are five reserves in the Sundarbans:
  • The Royal Bengal Tiger Reserve
    
  • Sundarban National Park
    
  • Sajnekhali wildlife sanctuary
    
  • Lothian Island wildlife sanctuary
    
  • Holiday Island wildlife sanctuary
    
  
  

In Focus: Mangroves

What are Mangroves?

• Mangroves are a group of trees and shrubs, also called halophytes, that live in the saline or brackish water of the coastal intertidal zone.
  
• They are referred to as ‘tidal forests’ and belong to the category of ‘tropical wetland rainforest ecosystem’.
  
• Mangrove forests occupy around 2,00,000 sq. km across the world in tropical regions of 30 countries. India has a total mangrove cover of 4,482 sq. km.
  
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• Mangrove forests only grow at tropical and subtropical latitudes near the equator because they cannot withstand temperatures below 5^o
  
• It is an interface between terrestrial forests and aquatic marine ecosystems.
  
• There are about 80 different species of mangrove trees. All of these trees grow in areas with low-oxygen soil, where slow-moving waters allow fine sediments to accumulate.
  

What is the significance of mangroves?

• The structural complexities of mangrove vegetation create unique environments which provide ecological niches for a wide variety of organisms.
  
• Mangroves serve as breeding, feeding and nursery grounds for most of the commercial fishes and crustaceans on which thousands of people depend for their livelihood.
  
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• Mangroves act as shock absorbers. They reduce high tides and waves and help prevent soil erosion.
  
• Mangroves give protection to the coastline and minimise disasters due to cyclones and tsunami.
  
• Mangrove forests are able to store three to four times more carbon than the forests which are found on land.
  • They form ecosystems which scientists refer to as “blue carbon ecosystems” as opposed to “green carbon ecosystems” which are found on the land.
    
  
  
• Mangroves are an intermediate vegetation between land and sea that grow in oxygen deficient waterlogged soils which have Hydrogen Sulphide (H₂S).
  • They perform important ecological functions like nutrient cycling, hydrological regime, coastal protection, fish-fauna production, etc.