Mangroves of Gujarat coast
Gujarat is the western most state of India and the total length of the coast line,
facing the Arabian Sea is about 1600 km; situated within the longitude 68 E and
73 E and latitude 20 10 N and 23 10 N.
Based on the geographical situation geomorphological position and variable
natural land, the Gujarat coastal zones may be divided into 5 regions
The Rann of Kachchh
The Gulf of Kachchh
The Gulf of Cambay (Khambhat/ Khambyat)
The Saurashtra coast
The South Gujarat coast
Out of these five regions , the two Gulfs constitute the major mangrove zones of
the Gujarat Coast.
Several minor rivers, viz. The Luni, the Mahi, the Narmada the Tapti and the Gulf
of Kutchchh and Gulf on Cambay have divided the entire coastline, where the
highest tidal amplitude rises upto 10.2 m from the Mean Sea Level at Bhavnagar
Rann of Kuchchh : This area is the extreme western part of India and also
divided into two regions i.e. Grear Rann, which covers about 10,500 km2 and
Little Rann, which covers about 3,000 Km2. Both these regions are saline desert
along with arid climate, though during monsoon months i.e. July to September,
these Indus delta inundate with the upstream fresh water flow along with tidal
ingress from several minor creeks, water ways. Canal and over bank splays.
Gulf of Kachchh : This region is extended between the latitude 22 15 N and 23
00 N and longitude between 69 00 E and 70 30 E.. It has 2,483 ha nad 12,800 ha
mangrove zones in the northern coastal and southern coastal zones respectively
in the Gulf of kuchchh. This extensive Gulf of Kachchh contains both mudflats
and cliffed, rocky islands with finged coral reefs and scattered mangals. Gujarat
government has declared 455.92 km2 area as Marine Sanctuary from Okha to
Jodiya. An area of 162.89 km2 area is notified as 'Marine National Park". This
'Marine National Park' is very much important ecologically, with its unique coral
reefs, mangroves and other interesting salt water adapted flora and fauna
Saurashtra coast or Kathiawar
Several islands, tidal flats, minor estuaries, embayments and beaches and rows
of dunes are also present in the Saurashtra coast.
Gulf of Khambhat (Cambay) : This zone lies between the latitude 20 30 N and 21
30 N and longitude 70 00 E and 73 00 E.. This Gulf area is characterized by the
estuaries, like the Sabarmati, the Mahi, the Narmada, the Kim, the Dhandhar and
the Tapti; extensive mud flats, dunes, scattered sandy beaches which makes this
Gulf very much diverse ecotype. Because of the diverse nature and number of
estuaries, these zones are also known as "estuarine delta"
South Gujarat coast : This uniform coast land is broken by several small tidal
creeks and few minor estuaries, like the Mindhola, the Purna, the Ambica, the
Auranga, the Daman Ganga. Mudflats and marsh vegetation is also present
Maharashtra coast
The total length of the Maharashtra coast is characterised by pocket beaches
flanked by rocky cliffs, these are estimated about 720 km long out of which the
mangrove cover was assessed 210 km2. The Maharashtra coastal zones
extends between the latitude 15 52'N and 20 10'N and longitude 72 10'E and 73
10'E and falls under five districts from South to North
Sindhudurg District
Ratnagiri District
Raigad District
Bombay District
Thane District. Here the mangrove zones are much degraded. During the last 25
years about 40% mangrove area in the Maharashtra coast reduced for constant
anthropogenic pressure, particularly by the 'Kharland Development Board' of
Maharashtra.
Satellite Imagery data shows that in Maharashtra and Goa coast the mangrove
areas is only 148.4 km2 on the mouth rivers like the Vashishti, the Thane, the
Vaitarana. The minor areas are Ratnagiri, Raigad, Thane, Bombay, Sindhudurg,
Mahim, Elephanta Island, Waghotan, Rajapur, Dharmatar, Vasai (Ulhas), Shastri,
Vikroli etc.
Goa coast
This coastal region is situated in the Central-Western Coast of India, facing the
Arabian sea and extended North to South. The total length of the coast line of
Goa is approximately 120 km and within the latitude 15 00'N - 15 52'N and
longitude 73 30'E - 74 44'E. These inter-tidal zones of seven minor estuaries are
mostly the flat lands and formed with silty-sand and silty-clay along with
abundant organic matters.
The minor estuaries /rivers in this coastal zone are the Terekhol, on the border of
Maharashtra and Goa
The Chapora
The Mandovi
The Zuari
The Sal
The Talpona
The Galgibag on the border of Goa and Karnataka
Beside these the connecting Cumbharjua canal links the Mandovi and Zuari
On both the sides of these minor rivers the soils are mostly alluvial and lateritic
soil with high percentage of Iron (Fe) and Manganese (Mn).
The major mangrove zones are extended in the Zuari estuary 9km2 and
Mandovi estuary 7 Km2 and the remaining 4 km2 spporadic mangrove patches
are distributed in the remaining 4 estuaries and the cumbharzua cannal
connecting Mandovi and Zuari estuaries.
The Sundarbans Biosphere Reserve can conviniently be subdivided into 6 main
localities depending on specific characteristics of different delta lobes and
different sweet water conditions from west to east.
Sagar-Mahisani-Ghoramara-Sand Head group of islands (Zone I)
These islands are essentially recent ones made of sandy upper strata, situated at
the estuarine mouth of river Hoogly over an area of 90 sq.km. About 15 sq.km.
would be restoration zone and 75 sq.km. would be manipulation zone
(Agriculture). The salinity of the soil in these sandy islands is reduced by
leaching. There lies a sewwt water lense at a depth of 40 ft. which made this
part more attractive. Winder irrigation in a small scale could give rise to large
scale rabi production of water melon and chilli. The sweet water of river hoogly
has the only influence in this zone and owng to release of water from the Farakka
barage, there has been some changes in the salinity regime. The islands show
signs of natural regeration of Heritiera fomes. Other effects demand urgent
investigation.
Mahisani island on west and Thakuran river on east over an area of 900 sq.km.
(Zone II)
This area covers 200 sq.km. of restoration zone and 700 sq.km. of manipulation
zone (Agriculture). This is the second delta lobe of the 5 lobed Sundarbans
delta. This zone is characterised by a transitional effect of lack of sweet water
flow. The planktonic production shows a preponderance ofCapepadas
(Zooplnakton) and Diatoms (Phytoplankton) typical of sheltered estuary. The
aquaculture activities are more restricted to silvopisciculture than agropisciculture. Silvopiscicultural farms for rearing Tiger Prawn has been set up by
Forest Department. The Kakdwip island prawns are reared in controlled
conditions in this zone. There is a crocodile breeding farm at Bhagabatpur island
and a wild life santuary at Lothisn island.
The zone between the rivers Thakuran and Matla over an area of 1600 sq.km.
(Zone III)
The portion of delta lobe is completely detached from any upstream flow and is
facing the undeterred effect of rushing back waters. The area of forest is 1400
sq.km. which falls within manipulation zone (Forestry) and restoration zone would
be around 30 sq.km. out of the forest area which is highly degraded state on
northern portion. Balance 200 sq.km. would be the manipulation zone
(Agriculture). The aquaculture here comprise of a combination of silvo and
agropisciculture. Sundarbans Development Board has already stated a
silvopiscicultural farm over a large area in Herobhanga island. Restoration of
northern forest blocks is badly necessary by enrichment planting augmented
protection and curbing export of forest produce to metropolis. The area of 1400
sq.km. mangrove forests needs immediate conservation approach until it is too
late and the area turns into Phoenix swamps as a biotic subclimax.
The area of Sundarbans Tiger Reserve's core area lying between the rivers
Matla in west, Haribhanga on east and on the north bounded by the rivers
Netidhopani and Gosaba over 1700 sq.km. area where interference is already
minimum, will serve as the 'Core zone' of Biosphere Reserve. An area of 1330
sq.km. has already been declared as National park in order to ensure strict legal
protection.
The buffer zone of Sundarbans Tiger Reserve over 885 sq.km. would come
under manipulation zone (Forestry). This area holds a game sanctuary over 365
sq.km. mangrove forests. This is the exploitation zone of Sundarbans Tiger
Reserve based on the sound principles of conservation management. This area
thus need to be continued as an example of manipulated forests with
conservation approach. The eastern end of the forest receives a tickle of sweet
water flow from the river Ichhamati, unlike the forest under zone III.
The area north of forest area lying to the west of river Matla.
This zone receives some trickle of sweet water from the Ichhamati river and is
traditionally practising Aquaculture, Agrofishery etc. This zone would naturally fall
within the manipulation zone (Agriculture) over an area of 4455 sq.km. Unlike all
other zones, this area is relatively more advanced in agriculture and aquaculture.
The lions share of Tiger Prawn comes from this zone. Agro-fishery has received
lot of public support within this relatively less saline creek areas. The easterly
flowing effect of Ganges through tributaries of river Padma makes the area more
characteristic within the proposed Sundarbans Biosphere Reserve.
Gulf of Mannar
Location
This marine Biosphere Reserve in the state of Tamil Nadu, is the first of its kind
in India and southeast Asia. It is situated in the Indian part of the Gulf between
India and Sri Lanka. It covers an area of about 10,500 sq.km., running southeast
and parallel to the main coastline to a distance of about 170 nautical miles. It is
an area of about 21 islands from the northern most Pamban to Tuticorin. The
total island area is about 555 ha.
Latitude
8 35' - 9 25' N
Longitude
78 8' - 79 30' E
Total area
Island area 555 ha. Gulf area is 10,500 sq.km.
Whether it includes any National Park/ Sanctuary etc.
Marine National Park
Climate
The Gulf is influenced by both south west (from April to July) and north east
(October to Decmber) monsoonal rains
Flora
The Gulf of manar with its islands privide a unique habitat for the living organisms
that are in close intimacy with sea water. About 160 sp. Of algae alone have
been recorded so far, of which some 30 sp. Form the eadible seaweeds.
Gelidiella acerosa is the most exploited sp. The islands have rich algal beds of
Lithothamnion, Padina, Caulerpa (10 sp.) Ultra reticulate, Sargassum, Martensia,
Claudia, Anadyomena stc. Although no marine docit has been recorded, the area
is rich in sea grasses belonging to families, Hydrocharitaceae and
Potamogetonaceae. The seagrass beds provide food for sea mammals,
particularly Dugong dugon. The mangrove vegetation of island consists of
species of Rhizophora, Avicennia, Bruguiera and Ceriops
Fauna
The Gulf area has several beautiful coral reefs that are exposed during the
lowest tide. The coral reef harbour a wide variety of marine vegetation and
animals. The algal species found are Halimedaopuntia, Caulerpa recemosa,
Sargassum sp. The conspicuous coral genera are : Aeropora, Galaxea, Leptoria,
Porites, Symphythea, Meruhins, Platygyra etc. The coral reesa are fast
deteriorating due to human interference, ad greater silt inflow from mainland.
Legally, quarrying of coral is now banned. The Gulf also has very productive
beds of sacred chank Xancus pyrsum. It is also famous for its pearl fisheries.
There are about ten pearl banks. The most preferred species of pearl oyster is
Pinctada fucala. The sea mammal Dugong dugon (sea cow) ocuures in Gulf of
mannar and the Palk Bay.
People
Fishing is the main activity and source of income for the inhabitants in the coastal
region. For the entire Gulf of Mannar stretch, there are about 40,000 fisherman
households, 150 fish landing centres and about 200 fishing villages
*******************
The Gulf of Mannar island posses unique mangrove vegetation. It is interesting to
note that such vegetation consists of species belonging to Rhizophora,
Avicennia, Bruguiera, Ceriops, Lumnitzera etc. Although mangroves are obtained
on a good majority of the islands, this vegetation of Manalli is striking for its
luxuriance and diversity. They are not very tall trees, perhaps the height is
curtailed due to strong winds lashing here perennially and with greater velocity
during monsoons, periodical cyclones etc. The plants are healthy. The whole
island is carpeted as its were with pneumatophores wherever the mangrove
forests are formed. The mangrove were seen with flowers on the island during
December-January.
The species includes plants of Avicennia officinalis, Excoecaria agallocha,
Bruguiera cylindrica, Ceriops tagal, Lumnitzera racemosa . Many halophytes like
Suaeda maritime, Suaeda monoica, Arthocnemum indicum, Sesuvium
portulacastrum, etc. are also found.
Sundarbans Biosphere Reserve
Location
Located in delta of Ganges-Brahmaputra river system in West Bengal, south
'Dampier-Hodges Line'
Latitude
21 31' - 2245' N
Longitude
88 00' - 89 05' E
Total area 6,630 sq.km.
Whether it includes any national Park/ Wildlife Sanctuary/ Tiger Reserve
Sundarbans national Park, Sundarbans Tiger Reserve and 3 Wildlife sanctuaries
viz. Sajnakhali, Lothian Island and Halliday
Climate
The area falls under the inter-tidal zone and has a tropical humid climate. Annual
average rainfall is 1900 mm. Average salinity of water varies from 1.11% on east
and 2.37% total salt on west. Average tidal amplitude is 2.1 m. which reaches its
peak during the stormy months of March/April
Major physiographic features
Based on the physiographic characters of different delta lobes, the Sundarbans
Biosphere Reserve can be divided into 6 zones
1.
2.
3.
4.
5.
6.
Sagar-Mahisani-Gharamara-Sand group of islands at the estuarine mouth
of Hoogly river
Mahisani island on west and Thakuran river on east
Zone between the river Thakurana dn Matla
Core area of Sundarbans Tiger Reserve
Buffer are of Sundarbans Tiger Reserve
Area lying east of Matla river
**********
Core zone comprising of 1700 sq.km. of well conserved mangrove forest of
existing Sunderbans Tiger Reserve which includes 1330 sq.kms. forest of
"Sundarbans National Park".
Manipulation zone (Forestry) comprise of the balance Forest areas of this
mangrove tract over about 2400 sq.km. area.
Restoration zone include the balance degrade forest areas, the saline blanks
spread over the entire forest area and the degraded mud flats within the nonforest areas comprises of nearly 200 sq.km.
The balance non-forest areas come under Manipulation Zone (Agriculture) and
provide areas of investiigation for agriculture, aquaculture, agro-fishery, animal
husbandry, apiary, social adaptations and human settlements, archaeology, soil,
water and tidal resources management.
**************
Flora
The area is a unique highly productive mangrove ecosystem and is the richest
mangrove repository of India. It is the home of number of endabgered and
threatened species of plants. Some of the mangrove species are Avicennia alba,
Excoecaria agallocha, Ceriops decandra. All mangrove flowers are nectar
bearing and Sundarbans produces 50-60m tomes of honey every year.
Fauna
29 species of mammals, 144 species of birds, 55 species of reptiles and 7
species of amphibians have been recorded in Sundarbans. The enfangered
animal species are Royal Bengal Tiger, Fishing Cat, Gangetic Dolphin and King
Crab.
People, landuse and socio-economics
Nearly 24 lakh people now depend on the area under Sundarbans Biosphere
Reserve. The reclaimed intertidal lands are single crop lands for paddy where
winter-irrigation is not possible from saline tidal waters. Hence, people have to
depend on aquaculture, fishing, honey collection and wood cutting even bearing
the man eating tigers. As a result, people here live much below the poverty line.
Global Development
Man and Biosphere (MAB) Programme of UNESCO launched in 1971 aims at
developing a base for rational use or conservation of natural resources while
improving the relationship between the man and environment. Besides, this
objective is also to predict the consequence of man's enterventions on nature
today on tommorow's world and thus increase his ability for managing the natural
resource effectively.. It laso aims to fill the stillsignificant gaps in the
understanding of the structure and function of ecosystems and of the impact of
different types of human intervention.
The International Coordinating Council which supervises the MAB programme, at
its first session in 1971, decided that one of the themes of this programme was to
be the 'conservation of natural areas and genetic material they contain'. Under
this theme was introduced the concept of the Biosphere Reserve, which was
intended to be a series of protected areas linked through a coordinated
international network, which would demonstrate the value of conservation and its
relationship with develoment. The concept was innovative because of this
network character and because it combined Nature conservation with scientific
research, environmental monitoring, training, demonstrations, environmental
education and local participation.
Since the very beginning of the implementation of the concept of Biosphere
Reserve as representative ecological areas, the international Biosphere Reserve
network has formed a geographic focus for implementing the MAB Programme.
The first Biosphere Reserves were designated in 1976. Subsequently, the
network has grown steadily until 1984; it consists of total of 269 in 74 countries.
In this period, cooperation with other international organizations involved with
conservation and sustainable development has been strengthened; particularly
involved are the Food and Agriculture Organization (FAO), the United Nations
Environment Programme (UNEP) and the International Union for Conservation of
Nature and Natural Resource (IUCN). Representatives of these four
organizations meet together regularly through the Ecosystem Conservation
Group, to coordinate action.
The first international congress convened jointly by UNESCO and UNEP at
Minsk (USSR) in 1983 outlined the broad characteristics of the biosphere reserve
representing terresterial and coastal environment in various bio-geographic
provinces of the world
Each biosphere reserve has been designated to consist of
Nature or Core Zone : Managed for minimum human interference to serve as a
baseline for the biological region; research, educational and training activities are
carefully controlled and must be non-manipulative
Manipulative or Buffer Zone : Managed for research , education and training
activities, and manipulative methods and techniques are permitted. Traditional
activities including timber extraction, hunting, fishing and grazing are permitted in
controlled manner.
Reclamation of Restoration Zone : Managed to study and reclaim lands and
natural resources where heavy natural or human-caused alteration has passed
ecological threshold or where biological processes have been interrupted or
where species have become totally extinct.
Stable Cultural Zone : Managed to protect and study ongoing culture and land
practices which are in harmony with the environment. Local residents and their
activities be strictly controlled.