Red List of Mangrove Ecosystems: Study by IUCN

• Global assessment reveals a 50% risk of mangrove ecosystem collapse. Without further conservation, by 2050, 7,065 sq km more mangroves will be lost, and 23,672 sq km submerged.

If we let this happen, the world is at risk of losing:  

• 1.8B tonnes of carbon stored, costing society $336B (based on the social cost of carbon). Protects 2.1M lives and $36B worth of property from coastal flooding..

Sea-level rise is the main threat affecting mangrove ecosystems. 

• 25% of the global mangrove area is predicted to be submerged in the next 50 Years.
• 1/3 of the world’s mangrove ecosystem provinces will be severely affected by sea-level rise.

Back2Basics: Mangroves

• Mangroves constitute a group of trees and shrubs inhabiting the coastal intertidal zone.
• They are found globally in tropical and subtropical regions, typically between latitudes 25° N and 25° S.
• Mangroves are predominantly located in tropical regions due to their intolerance to the extreme cold conditions prevalent in temperate zones.

Features of Mangroves:

• Adaptation to waterlogged and anoxic soil: Mangroves possess unique characteristics allowing them to survive in waterlogged and oxygen-deficient environments.
• Halophytes: Mangrove species have the ability to filter out up to 90% of the salt from seawater as it enters their roots, with some species also excreting salt through glands in their leaves.
• Water retention capacity: Thick succulent leaves store fresh water, while a waxy coating on some species’ leaves minimizes evaporation.
• Pneumatophores: Certain mangroves develop pencil-like roots that emerge from the ground to absorb oxygen from the air, aiding in coping with tidal flooding.
• Prop roots: Many mangrove trees possess dense aerial roots descending from their trunks and branches, which stabilize and support them against waves and tides.
• Lenticellated bark: Oxygen enters mangroves through lenticels, small breathing pores in the bark and roots, enabling them to adapt to low oxygen conditions.
• Viviparity: Seed pods germinate while still on the tree, facilitating immediate root growth upon dropping.

Mangroves in India:

• According to the India State of Forest Report 2021, mangrove cover in India comprises 0.15% of the country’s total geographical area.
• West Bengal has the highest percentage of area under total mangrove cover among states and union territories, followed by Gujarat and the Andaman and Nicobar Islands.
• The Sundarbans, characterized by the dominant mangrove species sundari (Heritiera fomes), is the largest continuous mangrove forest globally.
• Various mangrove areas in India are protected within reserves and sanctuaries such as the Sundarbans Tiger Reserve, Bhitarkanika, Coringa, Nelapattu, Point Calimere Wildlife Sanctuaries, Pirotan National Park, among others.

PYQ:

[2011] The 2004 Tsunami made people realize that mangroves can serve as a reliable safety hedge against coastal calamities. How do mangroves function as a safety hedge?

(a) The mangrove swamps separate the human settlements from the sea by a wide zone in which people neither live nor venture out

(b) The mangroves provide both food and medicines which people are in need of after any natural disaster

(c) The mangrove trees are tall with dense canopies and serve as an excellent shelter during a cyclone or tsunami

(d) The mangrove trees do not get uprooted by storms and tides because of their extensive roots.