Wetlands
Introduction
India is very rich in wetland
habitats exhibiting different ecological diversities, climatic conditions and
changing topography. A great number of these wetland habitats have been affected
by various human impacts but realising the crucial role of the wetlands in
ground water recharge, ground water discharge, flood storage and
desynchronization, shoreline anchoring and dissipation of erosive forces,
sediment traping, nutrient retention and removal, food chain support, habitat
for fisheries, habitat for wild life, active recreation, passive recreation and
heritage value, Ministry of Environment and Forests, Govt. of India (1990) and
also IUCN (1989) published the directories of wetlands of India and Asia
respectively.
On
the basis of topographical variation, Indian Wetlands are of four major types-1) Himalayan Wetlands 2)
Wetlands in the Gangetic plain 3)
Wetlands in the desert and 4) Coastal
Wetlands. Along the 7,500 km coast line of India, there is a great diversity of
wetland habitat with lagoons, estuaries, mangrove swamps and coral reefs. Among
the coastal wetlands, coastal lagoons are the shallow coastal water bodies
separated from the ocean by a barrier connected at least intermittently to the
ocean by one or more restricted inlets and usually oriented parallel to shore (Phleger,
1981). Coastal lagoons are
usually found on low-lying coasts and are normally aligned with their largest
diameter parallel to the seashore. A
number of lagoons are distributed all along the East and the West Coasts of
India. There are 17 noteworthy
lagoons in Indian coast with 8 on the east and 9 on the west.
The 8 important coastal lagoons in the east are: 1) Chilka Lagoon 2)
Pulicat lagoon 3)
Pennar lagoon 4)
Bendi lagoon 5)
Nizampatnam lagoon 6)
Muttukadu Lagoon 7) Muthupet lagoon
and 8) Gulf of Mannar Lagoon.
The 9 important coastal lagoons in the West are: 1)
Vembanand lagoon 2)
Ashtamudi Lagoon 3) Paravur lagoon
4)
Ettikulum Lagoon
5) Veli
lagoon 6)
Murkumpuzha lagoon 7) Talapady lagoon 8)
Lagoons of Bombay coast and 9)
Lakshadweep Lagoons (Kavaratti and
Minicoy Lagoon).
Out of several wetlands in India, Chilka lake in the state of Orissa was designated as Ramsar site in 1991 as an internationally important of waterfowl habitat. Among the six Ramsar sites [Chilka Lake (Orissa), Keoladeo Ghana National Park (Rajasthan), Wular Lake (Kashmir), Harik Lake (Punjab), Loktak Lake (Manipur) and Sambar Lake (Rajasthan)] in India, Chilka Lake is the largest one and unique of its kind for its magnificent biological diversity, ecological complexity and sustainability. This vast water body spreading over an area of 1100 sq. km harbours innumerable number of both floral and faunal components. It is a haven for migratory birds, having 159 species/subspecies (Dev, 1997). More than 800 species of animals are reported from this lake and its vicinity by Zoological Survey of India (Ghosh, 1995). About 225 species of fish have been reported from this lake (Dean & Saaltink, 1991). On the banks of the lake there are 8 fairly large towns and 122 villages. About 70% of this population depend upon fishing as the only means of livelihood. A population of about 1,27,000 souls are directly dependent on fisheries in the lake and 50,000 cattles may get their fodder need from the margin and bank of the lake (Trisal and Chauhan, 1998). A revenue of over 70 million rupees, is collected from 24 revenue villages on its banks (Bandyopadhay & Gopal, 1991). Besides these, the lake attracts several national and international tourists for its pristine beauty and charming environment. On an average 2.5 lakh tourists visit this lake annually.