06-bioresourcesstatu.. - M. S. Swaminathan Research Foundation
06-bioresourcesstatu.. - M. S. Swaminathan Research Foundation
06-bioresourcesstatu.. - M. S. Swaminathan Research Foundation
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Vembanad Lake<br />
b. Kumarakom (9°37' N; 76°26' E)<br />
It is located by the side of Vembanad estuary the<br />
largest of its kind in Kerala as a continuous chain<br />
of about a kilometer in length. Tidal action in Fort<br />
Cochin is nearly 90 cm as recorded in the year<br />
1974. But a study in 1984 shows at present the<br />
tidal range is 20-60 cm. Major discharges into the<br />
estuary are the rivers such as Meenachal,<br />
Achancoil, Pamba, Manimala, and Moovattupuzha.<br />
The Kavanar, a tributary of the Meenachal River<br />
empties very near to the mangrove location.<br />
Construction of Thanneermukkam barrage and<br />
Thottapally spillway have changed the physicochemical<br />
properties of the water body in this part<br />
of the estuary with a host of other still unknown<br />
characteristics totally different from natural<br />
Vembanad estuary that existed two decades ago.<br />
c. Kannamali (9° 52' Nand 76° 16'E) :<br />
This mangrove is also in the Vembanad estuary<br />
near the bar mouth and hence the marine<br />
influence is very prominent. Area of the Cochin<br />
Corporation is a typical mangrove location. Thus<br />
mangroves are seen in Kumbalam, Trippunithura,<br />
Edappalli and Vypin besides the Mangalavanam of<br />
Cochin near the FCI godown and the surrounding<br />
artificial islands. Rivers Periyar and Varapuzha<br />
join the lake north of this part of the Vembanad<br />
Lake.<br />
d. Kumarakom :<br />
There is a mixed population of Rhizophora<br />
apiculata and Bruguiera gymnorrhiza running<br />
north to south bordering the Vembanad estuary.<br />
Pure stands of Sonneratia caseolaris is observed<br />
inside the sanctuary proper with a dense under<br />
growth of Phragmites karka (tall grass) suitable<br />
for perching birds. The Sonneratia trees are 10m<br />
high with a dense under growth of young saplings<br />
and seedlings of the mother tree. However,<br />
whenever openings are made, species such as<br />
Ardisia elliptica, Cerbera odollam, Hibiscus<br />
tiliaceus, Thespesia populnea, Terminalia<br />
catappa, Excoecaria agallocha, Heritiera<br />
littoralis do occur. Since the margins of the<br />
estuary is well protected by laterite walls, the<br />
characteristic natural zonation is unfortunately<br />
regulated (Ramachandran and Mohanan, 1987).<br />
The estuarine margins are pinged by Kandelia<br />
candel and Bruguiera gymnorrhiza, Rhizophora<br />
apiculata, Sonneratia caseolaris and Avicennia<br />
officinalis are observed up to the Barringtonia<br />
86<br />
racemosa zone where Heritiera littoralis,<br />
Calophyllum inophyllum, Hibiscus tiliaceus are<br />
also seen. Derris trifoliata, Caesalpinia crista,<br />
Salacia chinensis, Mucuna pruiriens, Argyeria<br />
sp and Anamirta coeculus are the climbers.<br />
Presence of Flagellaria indica is unique and it is<br />
the common climber masking the canopy. Littoral<br />
species such as Pongamia pinnata, Morinda<br />
citrifolia, Premna serratifolia, Lagerstroemia<br />
speciosa, Dolichandrone spathacea, Pandalus<br />
fascicularies etc. are present further inside along<br />
the bunds. Few cultivated taxa such as Cocos<br />
nucifera, Hevea braziliensis, Gliricidia sepium<br />
are also thriving well. Semiparasitics<br />
Loranthaceae like Dendrophthoe falcata and<br />
Viscum sp. are often found hanging on Kandelia,<br />
Rhizophora and Bruguiera sp. Acampe<br />
praemorsa an epiphytic orchid is rarely seen in<br />
the area. The inside canals support water plants<br />
such as Nymphoides indica, Salvinia molesta,<br />
Crinum defixum, Eichhorinia crassipes, Pistia<br />
stratiotes and Ludwigia adscendens.<br />
e. Kannamali (Edapalli, Cochin) :<br />
The areas adjoining Cochin and nearby islands at<br />
the mouth of Vembanad estuary used to be the<br />
single largest mangrove habitat in Kerala. The<br />
high population density of the area has<br />
deteriorated the mangrove. However, still in some<br />
pockets mangroves remain. Rhizophora<br />
mucronata attains its maximum development<br />
towards Kannamali. Avicennia officinalis has<br />
invaded most of the disturbed and reclaimed<br />
areas. Rhizophora mucronata fringes the<br />
margins of canals followed by R apiculata,<br />
Bruguiera gymnorrhiza & B cylindrica. On the<br />
tidal levels are Avicennia officinalis and<br />
Sonneratia caseolaris. Thick foliage of Acanthus<br />
ilicifolius, Acrostichum aureum is seen in areas<br />
with low salinity. Samadera indica and Hopea<br />
ponga are the species often found along with<br />
mangroves in Edappally region. Areas with more<br />
brackishwater influence support Typha<br />
angustata, Cyperus javanicus, Eichhorinia<br />
crassipes, SCirpus littorali, Cyperus pangorei<br />
etc.<br />
ii. Fauna<br />
The fauna is similar to any of the tropical rain<br />
forest. Among the endangered species of mammals<br />
Loris tardigradus, commonly known as slender