About mangrove ecosystem of andaman and nicobar islands

1. MM
Prepared By: Raheem pk
Department of ocean studies and Marine biology
Mangrove ecosystem

2. Introduction
 They are (Angiosperms) trees or shrubs growing in shallow and muddy salt
water or brackish waters
 Found mainly in tropical and sub-tropical inter-tidal regions of the world.
 Exhibit remarkable capacity for salt water tolerance
 Do not appear on sandy beaches and rocky shores.
 A muddy substratum of varying depth and consistency is necessary for
growth.

3. Mangrove cover in various parts of world (Source: Spalding et al.)
Region Mangrove
area(ha)
% to
Global
area
South and
Southeast
Asia
75,17,300 41.0
Australia 18,78,900 10.4
Americas 49,09,600 27.1
West Africa 27,99,500 15.5
Africa and the
Middle East
10,02,400 5.5
Total 1,81,07,700 100
Found throughout the world between
Latitudes 32°N and 38°S.
Around 80 species found throughout the
World (Saenger et al., 1983).

5. State wise mangrove cover (in sq.km.)
Sr.
No.
States/ union
territory Estimated by Forest Survey of India
1991 1993 1995 1997 1999 2001
1. Andaman
&Nicobar Islands
971 966 966 966 966 789
2. Andhra Pradesh 399 378 383 383 397 333
3. Goa 3 3 3 5 5 5
4. Gujarat 397 419 689 901 1031 911
5. Karnataka 0 0 2 3 3 2
6. Maharashtra 113 155 155 124 108 118
7. Orissa 195 195 195 211 215 219
8. Tamil Nadu 47 21 21 21 21 23
9. West Bengal 2119 2119 2119 2123 2125 2081
Total 4244 4256 4533 4737 4871 4481

6. Species of Andaman and nicobar
Acanthus ebracteatus
A. ilicifolius
A.volubilis
Aegialitis rotundifolia
Aegiceras corniculatum
Avicennia marina
White/Grey Mangrove
A. officinalis
Bruguiera cylindrica
B. gymnorrhiza
B. parviflora
B. exangula
Ceriops decandra
C. Tagal (Yellow mangrove)
Cynometra ramiflora
C. iripa
Excoecaria agallocha
Heritiera littoralis
Kandelia candel
Lumnitzera littorea (Black mangrove)
L .racimosa
Nypa fruiticans (Mangrove palm)
Phoenix paludosa(Mangrove date palm)
Rhizophora apiculata (Red mangrove)
R. lamarckii
R.mucronata
R. stylosa
Scyphiphora hydrophyllacea
Sonneratia alba (Mangrove apple)
S. apetala
S.caseolaris
S.griffithii
Xylocarpus granatum
X.mekongensis A very rare (Baratang and New Wandoor
only)
X.moluccensis

7. Sundarban Delta
The total land
area today is
4,143 km² .The
Indian part of
the forest is
estimated to
be about 19%,
while The
Bangladesh part
is 81%.

8. Mangroves of Sundarban
 Sundari (Heritiera fomes),
 Gewa (Excoecaria agallocha),
 Goran (Ceriops decandra) and
 Keora (Sonneratia apetala)
 The characteristic tree of the forest is the sundari (Heritiera
littoralis),
 Dhundul or passur (Xylocarpus granatum)
 Kankra (Bruguiera gymnorrhiza)
 Among palms, Poresia coaractata, Myriostachya wightiana
,golpata (Nypa fruticans)

9. Ecological succession
 Ecological succession is generally defined as the successive
occupation of a site by different plant communities.
 Succession began in the newly accreted land created by fresh
deposits of eroded soil.
 The pioneer vegetation is Sonneratia, followed by Avicennia
and Nypa.
 The late species to appear, is Excoecaria.
 As the level of land rises, the land is only occasionally flooded
by tides.
 Heritiera fomes begins to appear.

10. Zonation
Rocky &
Sandy
Sandy clay Silty clay Silt
Mangroves
absent
Sonneratia alba
Rhizophora mucronata
Avicennia marina
A. officinalis
Bruguiera gymnorrhiza
B. parviflora
Acanthus ilicifolius
Kandelia candel
Acanthus officinalis
Rhizophora mucronata
Aegiceras corniculatus
Sonneratia caseolaris
Cyperus sp
EUHALINE POLYHALINE MESOHALINE OLIGOHALINE LIMNETI
C
40-30% O 30-18% O 18-5% O 5-0.5% O <0.5% O
On the basis of salinity, five zones of mangrove distribution are considered-

11. Adaptation
Lenticels
Bruguiera gymnorhiza
Pneumatophores
Avicennia officinalis
Salt glands
Avicennia corniculata

12. 
Stilt root Prop root Hanging root

13. Knee root & buttress root
Heritiera littoralisBruguiera spp.

14. Reproductive strategy
Dispersal by means of water and vivipary.
Vivipary means that the embryo develops
continuously while attached to the parent tree.
Cryptovivipary (Greek kryptos, hidden)
refers to the condition whereby the embryo
grows to break through the seed coat but
not the fruit wall before it splits open.
This condition is exhibited by
Aegiceras,Avicennia and Nypa species.

15. Ecological Values
 The most productive natural systems
found throughout the world.
 Used by a vast array
of organisms as breeding ,
nursery and feeding areas.
 Foreshore protection, reducing
erosion by cyclones and
lessening the impact of storm surge.

16. Primary Productivity
 Function of a vegetation
community.
 Litter produced is measured in
kg dry weight ha-1 year-1
Leaf litter : the collection and measurement
of leaf litter fallen from a mangrove area
over a particular period of time

17. Food chain

18. Energy Pyramid

19. Bacteria:
 The tree is the foundation in a complex marine food chain and the detrital
food cycle.
 The detrital food cycle was discovered by two biologists from the
University of Miami, Eric Heald & William Odum, in 1969.
 As mangrove leaves drop into tidal waters within a few hours marine
bacteria that convert difficult to digest carbon compounds into nitrogen
rich detritus material.
 These same bacteria give mangroves their "rotten egg" smell - as the
sediment is oxygenpoor, only bacteria that use sulphur for energy can
survive.
 E.g – Bacillus sp. Lactobacillus brevis , L. fermentum , L.buchneri and
L. lactis , Pichia salicaria , Geotrichum sp., Pichia fermentans ,
Cryptococcus dimennae. Trichoderma asperellum , T. Aaggerssivum , T.
Spirale , T. polysporum

20. N-fixation
Atmosphere
Aerobic zone NH4+ NO2- NO3-
Anaerobic zone NH4+ NO3- N2 + N2O

21. Crustaceans as ecosystem engineers
 They modify, maintain and create habitats
 The topography of mangrove swamps often modified by mud
lobsters(Thalassina spp)
 Thalassina spp throw up waste material from beneath the mud
surface ,accumulates as mound of 1 or 2 m. in height, which
provide suitable habitats for others.
 Fiddler crabs are known to influence the productivity of
mangrove vegetation.

22. Fiddler crab
Uca sp.

23. Habitat
 Aquatic fauna
Benthic Community
Major groups represented by the benthic organisms are
molluscs, crustaceans, echinoderms, hydroids,
actinarians,planarians, nematodes, polychaetes and larval
forms of several other organisms.
Crabs -Scylla serrata
Mud lobster –Thalassina sp.
Pistol shrimps –Alpheus sp.
The molluscans - Crassostrea spp., Mytilus and Clams.

24.  Pelagic ommunity
The major aquatic mammals - dugongs, dolphins (Plantanista
gangetica), porpoises, otters.
Detritivorous species of fishes, crustaceans.
Fishes- Liza, Mugil, Lates, Polynemus, Sciaena,Setipinna,
Pangasium, Hilsa, Ilisha , Atroplus etc.
Prawns- Penaeus sp., Metapenaeus sp.,
In the upstream regions, giant prawns like Microbrachium
rosenbergii are also found in large quantities.

25. Plankton community
Representative phytoplankton taxa identified :
a) Bacteriastrum sp
b) Coscinodiscus sp
c) Chaetoceros curvesetus
d) Bacteriastrum hyalinum
e) Closterium
f) Asteronella
g) Grammatophora marina
h) Nitzschia sp
i) Navicula penata
j) Gyrosigma baticum
k) Anabaena
l) Asterionellopsis gracilis
m) Dinophysis norvegica
n) Polykrikos schwartzil.

26. Habitat
 Terrestrial fauna
Rhesus Macaque (Macaca mulatta)

27.  Sonneratia apetala is an important species for
wildlife, especially Chital deer (Axis axis)

28.  Endemic shrews , rats of Andaman & Nicobar
 Palm civet (Paguma larvata tyleri).

29.  Nicobar crab eating macaque (Macaca
fascicularis umbrasa)

30.  Royal Bengal tiger (Panthera tigris tigris)

31.  The reptile and amphibian fauna comprises
over 125 species .Reptiles include several
species of lizards,geckos, snakes and four
species of marine turtles.
 The mega species in the Andamans include
the king cobra (Ophiophagus Hannah), the
Andaman cobra (Naja sagittifera),
 Mugger crocodile (Crocodylus palustris), as
well as the Gharial (Gavialis gangeticus) and
the Water monitor lizards (Varanus salvator)

32.  The saltwater crocodile (Crocodylus porosus),

33. Water monitor lizard (Varanus salvator)

34. The king cobra (Ophiophagus
hannah),

35. Andaman cobra (Naja sagittifera)

36. Mangrove snake-Boiga
dendrophila

37. Yellow -crowned Night-Heron
Nyctanassa violacea

38. Oriental White eye
Zosterops palpebrosus

39. Boleophthalmus boddarti (blue-spotted

40. Adaptation of animal
Designed to survive
 Sessile organisms (like mussels and barnacles) survive the fast tidal
movements in mangrove forests by anchoring themselves to the roots.
 Mobile fauna avoid the tide by burrowing in the mud (crabs) or climbing
up and down tree trunks (monkeys).
 Lizards in mangrove habitat have a nasal gland that secretes salt into the
nasal cavity from which it is sneezed out.
 The keratinized skin of Crocodiles is relatively impermeable to salt and
water , they also use a number of salt glands located on the tongue.
 While sea turtles have salt glands modified into tear glands in their eyes.

41. Uses
 Used as a resource for food (commonly referred
to as bush tucker), medicine and timber.
 Mud crabs, long bums, periwinkles, mangrove
worms, mangrove jack, barramundi and many
other marine species are collected as bush tucker.
 Certain mangrove plants are used as food.
Avicennia marina fruit is eaten but only after
treatment to remove the bitter taste.

42.  Provide medicines-The ashes from burnt
Ceriops tagal wood is used to heal sores and
infections,
 The bark of Avicennia marina can be used to
treat stingray stings (Wightman,1989).
 Mangrove timber has also been used to
construct canoes,paddles, boomerangs and
spears.
 Foreshore protection, reducing erosion by
cyclones and lessening the impact of storm
surge.