197
3. According to Cowardin et al. ( 1979 ),
wetlands are land transitional between terrestrial and aquatic systems, where the water
table is usually at or near the surface.
4. Zoltai ( 1979 ) provided a Canadian defi nition
of wetland as areas where wet soils are prevalent, having a water table near or above the
mineral soil for the most part of the thawed
season, supporting a hydrophytic vegetation.
5. According to US National Academy of
Science, a wetland is an ecosystem which
depends upon constant or recurrent, shallow
inundation or saturation at or near the surface of the substrate. Presence of hydric soil
and hydrophytic vegetation is also common
diagnostic features of wetlands.
6. According to IUCN (Ramsar Convention)
(1971), wetlands are areas of marsh or artifi -
cial, permanent or temporary, with water (static
or fl owing), fresh, brackish or salt, including
areas of marine water, the depth of which at
low tide does not generally exceed 6 m.
7. Two distinct defi nitions of wetlands have
been formulated mainly to take care of situations where wetlands become the bone of
contention amongst different parties in connection with legal battles. Such defi nitions
are based as much on closing the loopholes
as on science. Such legal defi nitions have
been developed for two big users in the USA,
namely,
(a) For the US Army Corps of Engineers,
who may use to enforce its legal
respon sibilities.
(b) For the US Natural Resources Conservation Service to administer wetland protection under the so-called swampbuster
provision of the Food Security Act.
According to former, the term wetland
means, ‘those areas which are inundated
or saturated by a surface or ground water
at a frequency and duration suffi cient to
support and, that under normal circumstances, do support a prevalence of vegetation typically adapted for life in
saturated soil conditions’. According to
the latter, ‘wetlands generally include
swamps, marshes, bogs and similar areas’.
Notwithstanding the above, a choicest
defi nition of wetland is still lacking, although
attempts are being made to formulate a universal defi nition in order to accommodate
the needs of many users.
8. The origin and evolution of wetlands is,
perhaps, still shrouded with mystery. In
the cold belt, origin of wetland involves
receding of glaciers and the debris, which
are washed out of the melting ice, fi ll the
crevices near the edge of the ice sheet and
cover isolated blocks of melting ice. When
these ice blocks melt, the resulting depressions become isolated ‘kettle lakes’, etc .
Wetlands may also be formed by embankment
of valleys surrounded by hillocks. Wetlands
may also be formed by the action of beavers, etc .
9. Notwithstanding the above, Coles and Coles
( 1989 ) have dealt with people who live in
proximity to wetlands and whose culture is
linked to them as ‘wetlanders’. However,
wetlands, sometimes, had been depicted as
sinister and forbidding and as having little
economic value, e.g. in the Divine Comedy ,
Dante described a marsh of the Styx in Upper
Hell as the fi nal resting for the wrathful.
Further, centuries later, Carolus Linnaeus,
crossing the Lapland peatlands, compared
that region to that same Styx of Hell. Also,
people who study and have been associated
with wetlands have been belittled in literature. Hardy went down to botanise in the
swamp, while Meredith climbed towards the
sun. In addition to the above, the English language is fi lled with words which suggest
negative images of wetlands.
10. In addition to the positive and negative aspect
of wetlands, the wetlands still remain as
enigma to the scientists. There have been different conventions to deal with various
aspects of these signifi cant ecotones. Also,
there have been many organisations and
societies who deal with various aspects of
wetlands. Thus, with all the valuable uses,
the wetlands provide striking panorama of
aesthetics. Wetlands may be revered for their
manifold functions.
11.8 Origin and Evolution of Wetlands
3. According to Cowardin et al. ( 1979 ),
wetlands are land transitional between terrestrial and aquatic systems, where the water
table is usually at or near the surface.
4. Zoltai ( 1979 ) provided a Canadian defi nition
of wetland as areas where wet soils are prevalent, having a water table near or above the
mineral soil for the most part of the thawed
season, supporting a hydrophytic vegetation.
5. According to US National Academy of
Science, a wetland is an ecosystem which
depends upon constant or recurrent, shallow
inundation or saturation at or near the surface of the substrate. Presence of hydric soil
and hydrophytic vegetation is also common
diagnostic features of wetlands.
6. According to IUCN (Ramsar Convention)
(1971), wetlands are areas of marsh or artifi -
cial, permanent or temporary, with water (static
or fl owing), fresh, brackish or salt, including
areas of marine water, the depth of which at
low tide does not generally exceed 6 m.
7. Two distinct defi nitions of wetlands have
been formulated mainly to take care of situations where wetlands become the bone of
contention amongst different parties in connection with legal battles. Such defi nitions
are based as much on closing the loopholes
as on science. Such legal defi nitions have
been developed for two big users in the USA,
namely,
(a) For the US Army Corps of Engineers,
who may use to enforce its legal
respon sibilities.
(b) For the US Natural Resources Conservation Service to administer wetland protection under the so-called swampbuster
provision of the Food Security Act.
According to former, the term wetland
means, ‘those areas which are inundated
or saturated by a surface or ground water
at a frequency and duration suffi cient to
support and, that under normal circumstances, do support a prevalence of vegetation typically adapted for life in
saturated soil conditions’. According to
the latter, ‘wetlands generally include
swamps, marshes, bogs and similar areas’.
Notwithstanding the above, a choicest
defi nition of wetland is still lacking, although
attempts are being made to formulate a universal defi nition in order to accommodate
the needs of many users.
8. The origin and evolution of wetlands is,
perhaps, still shrouded with mystery. In
the cold belt, origin of wetland involves
receding of glaciers and the debris, which
are washed out of the melting ice, fi ll the
crevices near the edge of the ice sheet and
cover isolated blocks of melting ice. When
these ice blocks melt, the resulting depressions become isolated ‘kettle lakes’, etc .
Wetlands may also be formed by embankment
of valleys surrounded by hillocks. Wetlands
may also be formed by the action of beavers, etc .
9. Notwithstanding the above, Coles and Coles
( 1989 ) have dealt with people who live in
proximity to wetlands and whose culture is
linked to them as ‘wetlanders’. However,
wetlands, sometimes, had been depicted as
sinister and forbidding and as having little
economic value, e.g. in the Divine Comedy ,
Dante described a marsh of the Styx in Upper
Hell as the fi nal resting for the wrathful.
Further, centuries later, Carolus Linnaeus,
crossing the Lapland peatlands, compared
that region to that same Styx of Hell. Also,
people who study and have been associated
with wetlands have been belittled in literature. Hardy went down to botanise in the
swamp, while Meredith climbed towards the
sun. In addition to the above, the English language is fi lled with words which suggest
negative images of wetlands.
10. In addition to the positive and negative aspect
of wetlands, the wetlands still remain as
enigma to the scientists. There have been different conventions to deal with various
aspects of these signifi cant ecotones. Also,
there have been many organisations and
societies who deal with various aspects of
wetlands. Thus, with all the valuable uses,
the wetlands provide striking panorama of
aesthetics. Wetlands may be revered for their
manifold functions.
11.8 Origin and Evolution of Wetlands