373
Vegetation
About 233 species of AM belonging to 62 families have been recorded in Loktak Lake. Some of
these are Eichhornia crassipes, Nymphaea alba,
N. nouchali, N. stellata, Nymphoides indicum,
Nelumbo nucifera, Euryale ferox, Trapa natans,
L. var. bispinosa, Polygonum spp., Scirpus sp.,
Hydrilla verticillata, Ceratophyllum demersum,
Utricularia stellaris, Marsilea quadrifolia , etc .
Loktak also supports rare endemic plants like
Zizania latifolia and Iris bakeli .
Further, a Phumdi is formed by the binding of
accumulated soil particles and vegetable matter
by the roots of various aquatic plants and grasses.
There may be about 65 AM sp. in the formation
of a Phumdi, notably Eichhornia crassipes ,
Phragmites karka , Oryza sativa , Zizania latifolia , Cynodon spp., Limnophila spp., Sagittaria
spp., Saccharum latifolium , Erianthus pucerus ,
Erianthus ravennae , Leersia hexandra , Carex
spp., etc. Of these, Phragmites karka is said to be
the dominant species. In addition, Dinobryon,
Euglena, Ceratium , etc., are some of the abundant phytoplanktonic forms in Loktak.
Fauna
Out of 425 species of animals recorded, 268 species are vertebrates and 157 species are invertebrates. The inventory includes about 83 spp. of
fi shes, 5 spp. of amphibians, 31 spp. of reptiles,
116 spp. of birds and 32 spp. of mammals, including the ‘Sangai’.
Loktak is a wintering ground for about 21 species of migratory waterfowls particularly the
ducks, many of which migrate from different
parts of the Northern Hemisphere beyond the
Himalayas. However, population of migratory
waterfowls are said to be declining due to proliferation of phumdis. Further, trees support birds
of prey like the Milvus migrans lineatus and
Circus aeruginosus . Also, the Brown-backed
Hornbill, Rufous-necked Hornbill, Wreathed
Hornbill, the Pied Hornbill and the Great Pied
Hornbill are sometimes found in Loktak.
Some of the ichthyospecies of Loktak Lake
are the air-breathing fi shes like Channa punctatus, C. striata, Anabas testudineus and Clarias
batrachus . Further, Loktak is said to be a breeding
ground for Osteobrama belangeri, Labeo dero,
Wallago attu, etc. The annual fi sh production
from Loktak is approx. 1,500 tonnes. The State
Fishery Department of Manipur sometimes
releases many fi ngerlings of IMC and exotic
carps into Loktak Lake. A number of minihatcheries of the state government produce about
one million fi ngerlings in a day. Out of this, c
50 % of the fi ngerlings are released into Loktak
Lake, and the remaining are distributed amongst
the fi shermen. The indigenous Channa punctatus , Anabas testudineus , Anguilla , etc., are said to
be on decline.
There are rare animals like the Indian python,
sambar, barking deer, Eld’s Deer, wild bear, rhesus monkey, hoolock gibbon, stump-tailed
macaque, Indian civet, marbled cat and
Temminck’s golden cat. They live mainly in the
Keibul Lamjao National Park.
Further, Diffl ugia, Brachionus, Keratella,
Diaptomus, Crustacean larvae, etc., are some of
the zooplankton found in Loktak Lake.
Economic and Social Values
(a) Loktak Lake is a tourist spot, (b) the lake provides livelihood to more than one lakh people, (c)
its water irrigates about 40,000 ha of agricultural
land, (d) 60 % of the capture fi sh production of
Manipur State comes from Loktak, (e) aquatic
plants are harvested as food and for other commercial values and (f) the HE power project supplies 105 MW power.
Problems, Disturbances and Threats
(a) Loss of vegetal cover in the catchment and
the construction of Ithai barrage in the outlet, (b)
about 4,000 ha of the lake margin have been converted for paddy cultivation, (c) deforestation
and ‘Jhum’ (shifting) cultivation and certain
other land use practices in the catchment area
have accelerated soil erosion resulting in the
lake’s shrinkage due to siltation, (d) the nutrients
from catchment area and domestic sewage from
Imphal City carried by Nambul River into the
lake encourage the growth of water hyacinth and
phumdis, (e) encroachment in the lake area is to
be taken care of and (f) there is lack of integrated
approach. Further, (g) the construction of Ithai
20.2 Wetlands of Northeast India (The Water Wealth of Northeast India)
Vegetation
About 233 species of AM belonging to 62 families have been recorded in Loktak Lake. Some of
these are Eichhornia crassipes, Nymphaea alba,
N. nouchali, N. stellata, Nymphoides indicum,
Nelumbo nucifera, Euryale ferox, Trapa natans,
L. var. bispinosa, Polygonum spp., Scirpus sp.,
Hydrilla verticillata, Ceratophyllum demersum,
Utricularia stellaris, Marsilea quadrifolia , etc .
Loktak also supports rare endemic plants like
Zizania latifolia and Iris bakeli .
Further, a Phumdi is formed by the binding of
accumulated soil particles and vegetable matter
by the roots of various aquatic plants and grasses.
There may be about 65 AM sp. in the formation
of a Phumdi, notably Eichhornia crassipes ,
Phragmites karka , Oryza sativa , Zizania latifolia , Cynodon spp., Limnophila spp., Sagittaria
spp., Saccharum latifolium , Erianthus pucerus ,
Erianthus ravennae , Leersia hexandra , Carex
spp., etc. Of these, Phragmites karka is said to be
the dominant species. In addition, Dinobryon,
Euglena, Ceratium , etc., are some of the abundant phytoplanktonic forms in Loktak.
Fauna
Out of 425 species of animals recorded, 268 species are vertebrates and 157 species are invertebrates. The inventory includes about 83 spp. of
fi shes, 5 spp. of amphibians, 31 spp. of reptiles,
116 spp. of birds and 32 spp. of mammals, including the ‘Sangai’.
Loktak is a wintering ground for about 21 species of migratory waterfowls particularly the
ducks, many of which migrate from different
parts of the Northern Hemisphere beyond the
Himalayas. However, population of migratory
waterfowls are said to be declining due to proliferation of phumdis. Further, trees support birds
of prey like the Milvus migrans lineatus and
Circus aeruginosus . Also, the Brown-backed
Hornbill, Rufous-necked Hornbill, Wreathed
Hornbill, the Pied Hornbill and the Great Pied
Hornbill are sometimes found in Loktak.
Some of the ichthyospecies of Loktak Lake
are the air-breathing fi shes like Channa punctatus, C. striata, Anabas testudineus and Clarias
batrachus . Further, Loktak is said to be a breeding
ground for Osteobrama belangeri, Labeo dero,
Wallago attu, etc. The annual fi sh production
from Loktak is approx. 1,500 tonnes. The State
Fishery Department of Manipur sometimes
releases many fi ngerlings of IMC and exotic
carps into Loktak Lake. A number of minihatcheries of the state government produce about
one million fi ngerlings in a day. Out of this, c
50 % of the fi ngerlings are released into Loktak
Lake, and the remaining are distributed amongst
the fi shermen. The indigenous Channa punctatus , Anabas testudineus , Anguilla , etc., are said to
be on decline.
There are rare animals like the Indian python,
sambar, barking deer, Eld’s Deer, wild bear, rhesus monkey, hoolock gibbon, stump-tailed
macaque, Indian civet, marbled cat and
Temminck’s golden cat. They live mainly in the
Keibul Lamjao National Park.
Further, Diffl ugia, Brachionus, Keratella,
Diaptomus, Crustacean larvae, etc., are some of
the zooplankton found in Loktak Lake.
Economic and Social Values
(a) Loktak Lake is a tourist spot, (b) the lake provides livelihood to more than one lakh people, (c)
its water irrigates about 40,000 ha of agricultural
land, (d) 60 % of the capture fi sh production of
Manipur State comes from Loktak, (e) aquatic
plants are harvested as food and for other commercial values and (f) the HE power project supplies 105 MW power.
Problems, Disturbances and Threats
(a) Loss of vegetal cover in the catchment and
the construction of Ithai barrage in the outlet, (b)
about 4,000 ha of the lake margin have been converted for paddy cultivation, (c) deforestation
and ‘Jhum’ (shifting) cultivation and certain
other land use practices in the catchment area
have accelerated soil erosion resulting in the
lake’s shrinkage due to siltation, (d) the nutrients
from catchment area and domestic sewage from
Imphal City carried by Nambul River into the
lake encourage the growth of water hyacinth and
phumdis, (e) encroachment in the lake area is to
be taken care of and (f) there is lack of integrated
approach. Further, (g) the construction of Ithai
20.2 Wetlands of Northeast India (The Water Wealth of Northeast India)