Mangroves Flashcards
What are mangroves?
Shrubs or small trees that grow in coastal saline or brackish water.
They represent a characteristic littoral (near the seashore) forest ecosystem.
What conditions are required for them to grow?
These are mostly evergreen forests that grow in sheltered low-lying coasts, estuaries,
mudflats, tidal creeks backwaters (coastal waters held back on land), marshes, and lagoons of
tropical and subtropical regions. Their best locations are where abundant silt is brought down by rivers or on the backshore of
accreting sandy beaches.
Characteristics
- Salt tolerant trees (halophytes)
- adapted to harsh coastal conditions
- contain a complex salt filtration system and complex root system to cope with salt water immersion and wave action.
- adapted to the low oxygen (anoxic) conditions of waterlogged mud.
- produce pneumatophores (blind roots) to overcome the respiration problem in anaerobic soil conditions.
- require high solar radiation
- confined to only tropical + sub-tropical coastal waters
Mangroves occur in a variety of configurations. Name some
- Some species send
arching prop roots down into the water. - Other stands vertical “Pneumatophores” or air roots up from the mud.
- They range from bushy stands of dwarf mangroves found in Gulf of Kutch, to
taller stands found in the Sunderbans.
Stilt roots
Adventitious roots which emerged from the main trunk of a tree above ground level
Type of reproduction and why?
Viviparity mode of reproduction= seeds germinate in the tree itself before falling on the ground. It overcome the problem of germination in saline water.
Largest bloc of Mangroves in the world
Sunderbans
2nd largest in India
Bhitarkanika (Orissa)
Mangroves found in Gujarat
Avicennia marine, Avicennia officinalis and
Rhizophora mucronata = found in Gulf of Kutch and Kori Creek
Importance of Mangroves
- Eco- tourism
- Coastal protection
- Wildlife Habitat
- Clean water
- Carbon stores
How do mangroves protect coastal areas?
They absorb the energy of waves that pass through them. They can reduce the destructive force of storms by 90%. they also keep groundwater fresh and protect agri lands from salination.
Name imp species in these areas?
Royal Bengal Tiger
manatees
sea turtles
river dolphins
How does it maintain clean water?
Through retention, removal and cycling of nutrients, pollutants and particulate matter from rivers and land based sources
How does it help with carbon content in the atmosphere?
It can sequester 3-5x more carbon than rainforests. Most mangrove forests lay down peat-thick, heavy layers of carbon- rich soil that stays waterlogged and does not rot. About 10% of carbon they produce is sequestered in the soil = it remains in soil w/out cycling back to atmosphere
Threats to mangroves
- Natural threats = cyclones, overgrazing, damage by animals and marine creatures
- Anthropological threats= agri, coastal dev, shrimp farming, charcoal and lumber industries
SMART
Special Monitoring and Reporting Tool=
It monitors in the Sundarbans empowers local administration contributing to more effective management of natural resources.
Sunderbans were damaged in 2020 by…
Cyclone Amphan
Extent of Sunderbans
coastal region of Bay of Bengal, spread over India and B’desh, on delta of Ganga, B’putra, Meghna rivers
In 1973 a conservation effort was carried out for Sunderbans. What was it?
Creation of Sunderbans Tiger Reserve 1973
What was designated UNESCO World Heritage site and when?
1978= Sunderbans National Park
Sundarban Wetland was given importance in 2019 b/c…
It was recognized as the ‘Wetland of International Importance’ under the Ramsar Convention in January 2019.
Name some important wildlife creatures found in Sunderbans
Estuarine Crocodile, Royal Bengal Tiger, Water Monitor Lizard, Gangetic Dolphin and Olive Ridley Turtles.
Why are Mangrove forests imp?
They perform multiple ecological functions such as the production of woody trees, provision of habitat, food and spawning grounds for finfish and shellfish, provision of habitat for birds and other valuable fauna; protection of coastlines, and accretion of sediment to form new land.
State/ UT w/ highest % of mangrove cover?
WB followed by Gujarat and Andaman & Nicobar Islands
