Satkoshia Gorge Sanctuary
Upper Kolab Dam
Phulera, and Didwana Salt Lakes
Keoladeo National Park
Sardar Samand Reservoir
Som Kamla Amba Reservoir
West Banas Reservoir
Sacred Khechopalri Lake
Tamil Nadu 425
Point Calimere Wildlife and Bird Sanctuary
Gulf of Mannar Marine National Park
Wetlands of Nilgiri District
Vedanthangal and Karikili Tanks
Wetland in Madurai Agricultural College and Research Institute Campus
Karungulam and Sengulam Tanks
Puthupalli Alam Swamp
Uttar Pradesh 471
Manjhira Impoundment at Girija Barrage
Pyagpur and Sitadwar Jheels
Nawabgani Priyadarshani Bird Sanctuary
Dahar and Sauj (Soj) Jheels
Jheels in the Vicinity of Haidergarh
Wetlands of Eastern Uttar Pradesh
Upper Ganga River (Brijghat to Narora Stretch)
West Bengal 488
East Calcutta Wetlands
Brace Bridge Wetlands
Wetlands of Hugli District
Wetlands of Haora District
Wetlands in Jaldapara Wildlife Sanctuary
Andaman & Nicobar 516
Mangrove Wetlands of Middle Andaman
New Delhi 517
Jamuna River near Delhi
W etlands are among the most productive ecosystems in the world,
comparable to rain forests and coral reefs. They are repositories of
diverse species of microbes, plants, insects, amphibians, reptiles, birds, fishes and
mammals. The ideal climate, landscape (topology), geology, movement and
abundance of water help the flora and fauna inhabiting the wetland ecosystems.
Wetlands are “biological supermarkets”, which provide immense food that attracts
many animal species for completion of their life-cycle. The decaying dead plants and
animals in the wetlands are converted by bacteria into organic matter (detritus) that
are fed by many small aquatic insects, shellfishes and small fishes that are food for
larger predatory fishes, reptiles, amphibians, birds, and mammals.
What are Wetlands?
Wetlands are transitional zones between terrestrial and aquatic systems where the
water table is usually at or near the surface or the land is covered by shallow water.
‘Wetland’ is a generic term for water bodies of various types, and include diverse
hydrological entities, namely, lakes, marshes, swamps, estuaries, tidal flats, river
flood plains, peatlands, shallow ponds, etc. Wetlands must have one or more of the
three attributes viz. atleast periodically, the land supports predominantly hydrophytes;
the substrate has predominantly undrained hydric soil; and the substrate is non soil,
saturated with water or covered by shallow water at sometime during the growing
season of each year.
Definitions of Wetlands
The definitions, by Cowardin et al. (1979), are widely accepted by wetland scientists
of United States and are also used in India (Mitsch and Gosselink, 1993). According
to Cowardin et al. (1979), wetlands are zones (lands) where saturation with water is
the key factor determining the nature of soil development and the types of plant and
animal communities living in the soil and on its surface. Wetlands differ widely,
regionally with different soils types, topography, climate, hydrology, water chemistry,
vegetation and other factors including human disturbance.
About wetlands, it is very relevant to quote R. Brown in “Encyclopedia of Life
Science”, 1996 which reads, “The word wetlands seems to contradict itself. How can
something that is wet really be considered land? Why is wetlands, simply not a lake or
a stream? Wetlands are the places where the two great natural components that cover
our Earth-land and water- wet and mingle to support life forms that are often different
from those that dwell only on land or only in water”.
The World Book Encyclopedia (1996), USA, defines “Wetlands is an area of land
where the water level remains near or above the surface of the ground for most of the
year”. The term “Aquatic”, according to Oxford Advanced Learner’s Dictionary
(Encyclopedia Edition, 1992) refers to plants and animals, etc. growing or living in or
near water: The Chambers Dictionary (New Edition, 1993) adopts the same
definition. Both these dictionaries refer to marshy areas as wetland (a marsh being
defined as low lying wetland, swamp or fen). Ralph A. Luken (1976) in “Preservation
versus Development”, defines “The term wetland is synonymous with bay lands and
includes submerged land, tide land, swamp and over-flow land”.
As such, it seems, the experts do not specifically define wetlands as a very distinct
ecosystem and consider such land synonymous with aquatic substratum or in other
words ‘The Wetland Ecology’ is therefore synonymous with ‘Aquatic Ecology.’
Mitsch and Gosselink (1986) the frontline wetland scientists observe, “A precise
wetland definition that is satisfactory to all users has not yet been developed, because
the definition of wetland depends on the objectives and field of interest of the users.
Different definitions can result from the geologist, soil scientist, hydrologist,
biologist, ecologist, sociologist, economist, political scientist and public health
Wetland as special niche of the landscape caught the eyes of the ecologists and
biologists only in late 1960s. The Ramsar Convention (1971), the first global
Conservation Convention brought this subject to the international arena and framed
universally accepted wetlands, which reads: “areas of marsh, fen, peatland or water,
whether natural or artificial, permanent or temporary with water i.e., static or flowing,
fresh, brackish or salt, including areas of marine water the depth of which at low tide
does not exceed six meters”. As such it becomes different to clacify other aquatic
bodies in to wetland group. In order to prepare a status of wetlands in United States,
the United State Department of Interior, Fish and Wildlife Service Authority,
however, adopted the definitions of Cowardin (1979) which is given under:
“The wetlands are lands transitional between terrestrial and aquatic systems where the
water table is usually at or near the surface or the land is covered by shallow water.”
Moreover, this definition includes several attributes which are:
• At least periodically the land must support predominantly hydrophytes.
• The substrate is predominantly undrained hydric soil.
• The substrate is non-soil and is saturated with water or covered by shallow
water sometime during the growing season of each year.
This definition emphasises three key attributes of wetlands: (i) hydrology –the degree
of flooding or soil saturation: (ii) wetland vegetation (hydrophytes); and (iii) hydric
soils. This definition has been broadly followed as it specifies various attributes of
wetlands. This definition does not contradict IUCN’s definition but only specifies the
parameters to be used for identification.
The Ministry of Environment & Forests (Govt. of India) has adopted the definition of
Wetlands which is given by the Convention on wetlands of International Importance
Classification of Wetlands by IUCN
IUCN identified a total of 39 categories of wetlands of which 30 are natural wetlands
and nine man-made. In it there are seven landscape units viz., estuaries, open coasts,
flood plains, freshwater marshes, lakes, peatlands and swamp forests. Freshwater
wetlands are haors, beels, jheels, oxbow lakes and flood plains. The table below
shows the classification of wetlands.
Wetlands Classification (Dugon 1990)
Marine 1. Subtidal (i) Permanent unvegetated shallow waters less than
6m deph at low tide, including sea bays, straits.