Mangroves Flashcards
Mangroves
It’s a special type of vegetation
Found in inter tidal regions were freshwater and saltwater inter mix like, bays, estuaries, creeks and lagoons etc
Mainly between latitude 25° north and 25° south
They cannot bear freezing temperatures
Salt tolerant variety of plants, which can survive in harsh conditions
Mangroves replace tidal marshes in tropical
Many species have root extensions called pneumatophores that take in oxygen for the roots
Prop roots and pneumatophores slow the movement of tidal water
World view
Location of mangroves are Atlantic coast from Florida till Argentina in a vast expansion
Mangroves grow on both the Western and Eastern coast of Africa, India, Burma, SE Asia, New Zealand and Australia
Types of mangroves
Red mangroves grow along coastlines. They are the hardiest of three major mangrove plant types
Black mangroves usually grow at slightly higher elevations than red mangroves. They have access to more oxygen because roots are more exposed
White mangroves grow at a higher elevation than red and black mangroves. Generally they do not have aerial roots. But sometimes there is unique grows of peg roots when oxygen is depleted due to flood
Mangroves in India
Found in West Bengal, Orissa, Andhra Pradesh, Tamilnadu, Kerala, Karnataka, Goa, Maharashtra, Gujarat, Andaman and Nicobar Islands
Found in Deltaic areas of Mahanadi, Godavari & Krishna river basins
India has world’s 3% of total mangrove area
Its major concentrations are in Sundarban delta and Andaman and Nicobar Islands
The Government of India formed the Indian mangrove committee in 1976
The MS Swaminathan Research Institute in Chennai, is engaged in the management of mangroves in the states of Tamilnadu, Andhra Pradesh and Orissa.
Characteristics of mangroves
Evergreen land plants growing on sheltered shores on tidal flats, deltas, estuaries, bays, creeks & barrier Islands
Locations are silt broad down by rivers or on back shore of accreting Sandy beaches
Physiological adaptation to salinity, stress and to water logged anaerobic mud high
Requires high solar radiation and have ability to absorb freshwater from saline or bracket water
Produce pneumatophores (blind roots) to overcome respiration problem in anaerobic soil condition
Enhances natural recycling of nutrients
Supports numerous flora, fauna and avifauna
Edge effect can be seen here
Supplies raw materials like wood, medicinal plants and edible plants
Prevent coastal soil erosion
Protects coastal land from Tsunami, hurricane and floods etc
Recreation and tourist attractions
Pneumatophores
Mangroves occur in a variety of configuration
Some species (rhizophora) send arching prop roots in water
Others (avicennia) send vertical Pneumatophores or air roots up from the mud
Some secrete excess salt through leaves
Others block absorption of salt at their roots
Adventitious roots emerging from main trunk of tree above ground level is called stilt roots
Mangrove profile in India
Top 5 states with maximum mangrove cover: West Bengal, Gujarat, Andaman and Nicobar Islands, Andhra Pradesh & Orissa
Sundarbans (West Bengal):
Largest single block of tidal holophytic mangroves of world
Species found are herritiera fames, rhizophora spp, bruguiera spp, ceriops decandra, sonneratia spp, avicennia spp, nypa fruticans found along creeks
Forest famous for royal Bengal tigers and crocodiles
Area cleared for agricultural use
Bhitar Kanika (Odisha):
Second largest in Indian subcontinent
Harbours high concentration of species and high genetic diversity
Swamps occur in inter tidal mud flats on sides of creeks in Godavari Krishna deltaic regions of Andhra Pradesh
Mangroves of pichavaram and vedaranyam degraded due to construction of aquaculture ponds and salt pans
West coast of India:
Scrubby and degraded
Occur along the inter tidal region
Creeks in Maharashtra, Goa and Karnataka
Mangrove vegetation in coastal zone of Kerala is very sparse and thin
North West coast
In Gujarat’s Gulf of Kutch, avicennia marine, avicennia officinalis, rhizophora mucronata found.
Mangroves of scrubby type with stunted growth, forming narrow discontinuous patches on soft clayey mud
In size, it ranges from bushy stands to dwarf
Andaman and Nicobar Islands:
Small tidal estuaries
Neritic inlets
Lagoon support
Dense diverse undisturbed mangrove flora
Role of mangroves
Plants with special roots
Prop roots, pneumatophores help to impede water flow
Enhance deposition of sediment in areas stabilizing coastal shores
Provide breeding ground for fishes
Moderate monsoonal tidal floods and reduce inundation of coastal lowlands
Prevents coastal soil erosion
Protects coastal lands from Tsunami, hurricanes and floods
Enhances natural recycling of nutrients
Supports numerous flora, avifauna and wildlife
Provides safe and favourable environment for breeding, spawning and rearing of several fishes
Protects coastal in land from adverse climatic elements
Supplies wood, firewood, medicinal plants and edible plants to local people
Provides numerous employment opportunities to local communities that augments livelihood
Threats to mangroves
Natural threats:
Cyclone typhoons and strong waves
Browsing and trampling by wildlife
Damage by oysters do young leaves and plumules of rhizophora and ceriops plants
Insects and pests like wood borers, caterpillars, etc
Human activities:
Indiscriminate tree felling and looping, mainly for fuel wood, fodder and Timber
Indiscriminate conversion of mangroves on public lands for aquaculture like, prawn culture at chorao (Goa), agriculture mining (mapusa estuary in Goa), human habitation and industrial purposes
Encroachment on publicly owned mangrove forest lands, cultivation of paddy observed on government land which involves uprooting of natural and planted seedlings
Lack of interest of private land owners in conserving and developing
Illegal large scale collection of mangrove fruits for production of medicines
Discharge of industrial pollutants into creeks, rivers and estuaries
Obstruction and diversion of water for culvert construction
Legal and regulatory approaches for protection
Legislations like coastal regulation zone notification 1991, environmental impact assessment of 1994, monitoring of compliance by regional offices of ministry and state pollution control boards, Indian forest act of 1927 and forest (conservation) act of 1980
Mangroves for future initiative by multiple countries. Multi sectoral partner lead initiative which builds on long history of coastal management interventions
Lessons learn during the coast of post Tsunami reconstruction and rehabilitation
Mangroves for future is being coordinated by IUCN
India has agreed to participate in IUCN-MFF initiative
Its objectives are: to strengthen environmental sustainability of coastal development and to promote investment of funds and effort in coastal ecosystem management for sustainable development
Mangroves conservation and sustainable developmental goals:
Importance of restoration and protection of mangroves is amply reflected in SDG 14.
But restoring mangrove forests also supports the achievement of many other SDGs like, eliminating poverty and hunger (1&2), ensuring lively goods and economic growth (8), taking actions against climate change impacts (13) and halting biodiversity loss (15)
India’s forest report of 2021
Prepared by the forest survey of India
Biannual report
Report is prepared after mapping forest and trees through satellite
Mangroves have also increase in coastal areas
Total mangrove area is recorded to be 4992 sq km
71.24 million tonnes of carbon stock recorded in country
The total forest and tree cover is 24.62% of the geographical area of the country
The total forest cover is 7,13,789 sq km, which is 21.71% of the geographical area of the country
The tree cover is 2.91% of the geographical area of the country
