Regional Environmental

problems of Mangroves loss

1. INTRODUCTION
2. ADAPTATION MACHANISM OF MANGROOVES
3. DISTRIBUTION OF MANGROOVES
4. IMPORTANCE
5. THREATS TO MANGROOVE ECOSYSTEM
6. NEED FOR CONSERVING
7. CONSERVATION OF MANGROOVES
8. MANGROOVES CONSERVATION AND SDG’S
 Introduction
A mangrove is a shrub or small tree that grows in coastal saline or brackish water. The term is also
used for tropical coastal vegetation consisting of such species
Mangroves are a variety of species of broad-leaved trees (10–40 feet high) lying in muddy creeks and
tidal estuaries. They are located on the intermediate zone between the land and the sea and represent
one of the best examples of ecotone. They require warm saline water and so they are situated along
tropical coastlines. Mangrove plants survive in the saltwater zones between water and land.
• Mangroves have a “complex salt filtration system” and complex root system to cope with salt
water immersion and wave action.They are also adapted to the low oxygen conditions of
waterlogged mud. Mangroves occur worldwide in the tropics and subtropics, mainly between
latitudes 25° N and 25° S. They require high solar radiation to filter saline water through their
roots. Hence, mangroves are confined to only tropical and sub-tropical coastal waters.
• It has been found that there are about 80 different species of mangrove trees. Mangroves grow in
areas with low-oxygen soil and in this soil slow-moving waters allow fine sediments to pile
u Mangrove forests only grow at tropical and subtropical latitudes near the equator as they cannot
bear freezing temperatures. Mangrove forests serve an important role in stabilizing and reinforcing
coastlands. In this way, they protect these coastlands from erosion that results from action of waves
and tides that occur regularly. They act as a shield against storms. This capability of the mangrove
forests has saved valuable property and countless lives around the world from imminent
destruction.
• Mangrove plants have several unique adaptations that allow them to survive in harsh
environments. Mangroves are extremely important to the coastal ecosystems they inhabit.
Physically, they serve as a buffer between marine and terrestrial communities. They protect
coastlines from damaging winds, waves, and floods. Mangrove has an important role in
improving water quality by filtering pollutants and trapping sediments from the land. They
reduce coastal erosion.
• Ecologically, they provide habitat for a diverse array of terrestrial and marine organisms.
The area of mangroves has greater species diversity as it is the junction of terrestrial and
marine ecosystems. They have very high salt tolerance and so some species which require
this ambience also thrive upon mangroves. According to one of its oft-quoted definition,
“Mangroves represent a characteristic littoral (near the sea shore) forest ecosystem and
they 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.
 ADAPTATION MECHANISM OF MANGROOVES
•Mangrove environment is very vital and robust. The mangrove species are adapted to deal with these
severe environmental conditions in multifarious ways.
•Breathing roots: Oxygen for the purposes of respiration is needed by the underground tissue of any
plant. As far as the mangroves are concerned, oxygen in the soil is in very limited supply. This means
that the mangroves take up oxygen from the atmosphere. For this purpose, mangrove species have
specialized above ground roots called breathing roots or pneumatophores. These roots have numerous
pores through which oxygen enters into the underground tissues. In some plants buttress roots
function as breathing roots and also provide mechanical support to the tree.
•Stilt roots: In some mangrove species, roots emerge from stems and branches. Such roots get into the
soil some distance away from the main stem as in the case of banyan trees. These stilt roots are
endowed with many pores through which atmospheric oxygen enters into the roots.
•Vivipary: It is postulated that “saline water, unconsolidated saline soil with little or no oxygen is not a
conducive environment for seeds to germinate and flourish. To overcome this, mangrove species have
a unique way of reproduction, which is generally known as vivipary”. This is a very unique method of
reproduction. In this method, seeds germinate and develop into seedlings while the seeds are still
attached to the parent tree. These seedlings are normally known as propagules. They photosynthesize
while still attached to the mother tree. The parent tree supplies water and necessary nutrients. They
remain buoyant and float in the water for sometime before rooting themselves on suitable soil.
 DISTRIBUTION
Global Distribution
•“About 40% of [the] world’s mangrove cover is found in South East Asia and South
Asia… India has about 3% of the total Mangrove cover in South Asia”
•There are 15.9 million hectares of mangrove forests in the warm waters of tropical
oceans all over the world. Along the Atlantic coast they are found from Florida till
Argentina in a vast expanse. Mangroves grow on both the western and eastern
coasts of Africa. They stretch into India, Burma, and south-east Asia. Mangrove
forests are also common in New Zealand and Australia.
Mangroves distribution in India

•“Mangrove cover in the country has increased by 54 sq km (1.10%) as compared to the previous assessment.”

•“The current assessment shows that mangrove cover in the country is 4,975 sq km [(1.2 million acres)], which is
0.15% of the country’s total geographical area.”

•They are found in the following states and Union Territories in India: West Bengal, Odisha, Andhra Pradesh,
Tamilnadu, Andaman and Nicobar Islands, Kerala, Karnataka, Goa, Maharashtra and Gujarat.

•The major concentrations of mangroves are in the Sunderbans delta and Andaman & Nicobar Islands. However,
the mangroves are also found in the deltaic areas of Mahanadi, Godavari and Krishna river basins.

•The Government of India formed an Indian Mangrove Committee in 1976. M.S. Swaminathan Research Institute,
Chennai is also engaged in management of mangroves in states of Tamil Nadu, Andhra Pradesh and Odisha.
 IMPORATNCE
•Mangrove forests give sturdy support to the coastline by minimizing erosion from storm surges, currents, waves, and tides. The intricate
root system of mangroves is unique as they allow them to shelter fish and other organisms in an ecologically benign environment.
For example, the area of Sunderbans is the world’s largest mangrove forest and they have wider species diversity.
This biodiversity hotspot is home to 180 species of trees and plants growing within its marshy boundaries, the Gangetic dolphin,
estuarine crocodiles, river terrapins, hawksbill turtles, horseshoe crabs and the famous Bengal tiger. They are a World Heritage site
and the biggest carbon-sink in South Asia. They have an important role in carbon sequestration and hence climate management.

•Mangroves are the first line of defence against cyclones and rising seas. They also support coastal communities in multiple ways.

CASE STUDY
TSUNAMI & MANGROVES Case Study
Pichavaram mangrove forest protected hamlets namely, T.S.Pettai, Vadakku Pichavaram, Therkku Pichavaram, Meenavar Colony,
MGR Nagar and Kalaingar Nagar against the fury of tsunami. Total families in these hamlets are about 1228 and total population is
about 6191. These hamlets are located between 100 m to 1000 m from mangroves. In these hamlets seawater has not entered into
the village and there is no loss of property. However, 4 women belonging to MGR Nagar, who were fishing nearby the sea were
washed away and died. It is seen that mangrove trees in rows located close to the sea got uprooted due to the impact of the
tsunami and beyond that there is no damage. It seems mangrove forest reduced the impact of the tsunami by two ways: a) velocity
of the tsunami water greatly reduced after it entered into the mangroves due to friction created by thick mangrove forest and b)
volume of water reaching a point is greatly reduced since tsunami water, after entering into the mangroves, is distributed to all the
canals and creeks that are present all over the mangroves. A number of fishers who were fishing in the nearby the sea but moved
into mangrove water after seeing huge wave of about 10 to 15 feet coming to the beach experienced these. One of the fishers said,
“we saved the mangroves by restoring them and it saved our life and property by protecting us” of about 10 to 15 feet coming to the
beach experienced these.)
•Mangroves provide important nesting and breeding sites for fish and shellfish, migratory birds and sea turtles. This
underscores their importance to coastal fishing communities. According to a global research, an estimated 80% of the
global fish catch relies on mangrove forests either directly or indirectly.

•About 20 percent of India’s population lives on the coast. There are many big cities including Mumbai, Chennai,
Puducherry, Thiruvananthapuram, Kochi etc. which lie on the sea shore. A robust and dense cover of mangrove forests
can protect these areas, which are vulnerable both to sea level rise and to the more intense and frequent weather events
caused by climate change.

•Mangroves also act as great carbon sinks. Some researchers at the global level have postulated that mangroves “isolate
carbon at two to four times the rate of tropical forests like the Amazon and store three to five times more carbon per
equivalent area than tropical forests”.

•Mangroves are used for timber, mining, agriculture, harbour development and human settlements. Mangrove areas were
used earlier for commercial shrimp farming. However, using mangrove areas for shrimp farming has proved to be
unsustainable now-a-days.

•Mangroves are an ecosystem with multi-dimensional use. It is held that they are the “best form of coastal bioshield” as they
perform a “critical role in reducing the impact of cyclonic storms, hurricanes and tsunami on human lives and properties”.

•It controls/reduces soil erosion. It magnifies fishery productivity of the adjacent coastal waters. This occurs as they act
as a nursery ground for commercially important fish, prawn and crabs. Additionally, they supply organic and inorganic
nutrients. They are also rich in biodiversity and act as habitats for wildlife.

•It is being held that “the physical environment lays the foundations and draw limits for how and where mangroves thrive, as
‘ecosystem engineers’ mangroves themselves are partially responsible for shaping their physical environment”.
 THREATS TO MANGROOVES
•They are destroyed for the conversion of the area for agricultural purposes,
fuel, fodder and, salinization, mining, oil spills, aquacultural (shrimp farming),
use of chemical pesticides & fertilizers, industrial purposes.
•From seas – Sea level rise, cyclones and tsunami, coastal erosion, oil spills
•From rivers – Polluted water
•From Communities– Destroyed for fuel, fodder
•Plastic bags and other waste is a major threat for mangroves.
•Goats can destroy mangrove seedlings and damage mature trees.
 NEED FOR CONSERVING
•Mangroves are immensely beneficial but unfortunately half of the world’s mangroves (about 32 million hectares) have already been cleared or destroyed and
the remaining ones are also facing grave threat.

•The mangrove forests are important for food, carbon storage and sequestration, coastal protection, tourism and water purification. Hence, there are
efforts made to halt further losses as well as to increase mangroves through restoration.

•Mangroves are faced with a lot of threats. For example, a large part of land has been cleared for establishing shrimp farms in Latin America and Southeast
Asia which have adversely impacted mangroves. Climate change, changing land-use patterns and tourism also affect the future of the mangrove plant.

•A serious impediment to the unhindered growth of mangroves is prompt and mostly unregulated coastal development. Although India has framed laws to
protect its coastline, they are breached quite often. According to a research by the Indian Institute of Science, “India has lost 40% of its mangrove area in the
last century, mainly due to agriculture, aquaculture, tourism, urban development and overexploitation”.

•The State of Forest Report, released by the Forest Survey of India, says that “the mangrove cover in the country is increasing only marginally in the past two
decades”. These facts very clearly illustrate that there is a lot to be done as far as the sustainable management and conservation of mangroves is concerned.
There is an urgent need to restore degraded mangroves by governmental action as well as participation of local communities.

•Many countries have realized the immense value of mangroves to the overall environmental sustainability. They have adopted mangrove restoration and
conservation programs. Strict legislation to protect mangroves is in place in many countries. For example, Indonesia has 25 percent of the world’s mangrove
population. Coastal fish farmers on the Indonesian island of Java are given 4–5 hectares of land. However, the rider is that these farmers are required to plant
mangroves on 20% of this land. Seeds are gathered from budding sprouts and planted 6 to 9 feet apart. This sort of reforestation improves the environment,
while feeding people and encouraging the economy. This is a sustainable long term solution devised in Indonesia.
Nurturing and nourishing mangroves helps fulfil multiple objectives like improving the life of aquatic animals, reducing poverty and
hunger, enhancing the quality of life of coastal communities etc. The importance of restoration and protection of mangroves is amply
reflected in Sustainable Development Goal (SDG) 14 (which focuses on sustainably governing our oceans and coasts and recognises
mangroves’ immense value to local communities). But restoring mangrove forests also supports the achievement of many other SDGs like:

•Eliminating poverty and hunger (SDG 1 and SDG 2),

•Ensuring livelihoods and economic growth (SDG 8),

•Taking actions against climate change impacts (SDG 13) and

•Halting biodiversity loss (SDG 15).

They do so in numerous ways. The mangroves have very rich species diversity. For example, India’s mangroves are home to 4,011 species
(the highest in the world). The mangroves give sufficient and nutritious food to local coastal communities. This becomes particularly useful
to poor and vulnerable populations. Various income-generating opportunities are offered by mangroves. The sustainable harvest of
mangrove products meant for market sales present business opportunities for local communities. This benefits women, native tribes,
farmers, pastoralists etc. These local income opportunities can be enhanced through the creation of management and planning jobs involved
in restoration projects. Mangrove forests are important in climate management as they are “carbon-rich protective buffer zones between land
and sea”. The restoration of mangrove forests is directly related to goals which are in sync with climate adaptation and mitigation. The
mangroves should be restored in order to promote the resilience of coastal communities from various climate-induced threats. It is
held that “mangrove restoration sites can also be strategically placed to contribute to upgrading infrastructure with greater adoption of
environmentally sound technologies through applying infrastructures for coastal protection”. In this way, the resilience of coastal
communities can be magnified by minimizing their exposure to climate-induced environmental shocks and disasters. It has been
acknowledged time and again that mangroves are extremely “efficient carbon sinks”. Hence, well-calibrated actions meant for
mangrove restoration efforts help in adapting to adverse impacts of climate change. Various scientific studies have attested the
importance of restoration of mangroves in smart climate management. There is a need for an integrated approach to mangrove
restoration. By this approach the local coastal communities can emerge as participatory stakeholders in the process of mangrove
restoration. The local people can have sustainable development lifestyles in harmony with nature and can also help the government in
promoting sustainable tourism. This will also enhance eco-friendly business opportunities for local communities in multiple ways.
•In 1976, the National Mangrove Committee was set up under the Environment
Ministry.
•In 1979 it recommended focus on areas like mapping of mangroves using remote
sensing, land surveys, etc., to determine degradation rate, assessing sites for
establishing reserve forests, conservation program, afforestation, R&D etc.
•Several legislations like Environment (Protection) Act, Indian Forest Act, Wildlife
Protection Act, Forest Conservation Act, etc. are sources of protection (though
mangroves are not specifically mentioned in all of these).
•In 2018, the High Court called the destruction of mangroves an offence to the
fundamental rights of the citizens under article 21 of the Constitution. Since then, the
government has been undertaking efforts to conserve the mangroves.
•In 2018, India along with 7 other countries of the Bay of Bengal region came
together to protect the mangroves under the BOBLME (Bay of Bengal Large Marine
Ecosystem) project. The UN Food and Agriculture Organisation leads this project. The
GEF (Global Environment Facility) approved a grant of 15 million USD for this project.