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Topography and Geology
The Beel is bounded by steep highlands on the
north and south. The Beel and its adjoining areas
were, perhaps, abandoned channels of the
Brahmaputra river system. The Beel soil represents recent alluvium consisting of clay, silt and
sand, while the highlands around the Beel are
made up of gneisses and schists of the Archaean
age.
Hydrometeorology
The climate is hot and humid under the infl uence
of tropical monsoon. The Beel is mainly fed by
the inlets, Basistha and Kalmani rivers and local
monsoon run-off between May and September.
The main outlet is the Khonajan channel, which
drains the Beel water into the Brahmaputra River.
It, thus, acts as a natural storm water reservoir
during the monsoon season for the Guwahati
City. Temperature in the Beel ranges from 9.3 to
38.4 °C. ‘Boro’ paddy is cultivated in the exposed
shoreline (up to about 1 km) of the Beel during
winter. Pre-monsoon showers occur generally
between March and May .
Flora
Eichhornia crassipes, Pistia stratiotes, Ottelia
alismoides, Lemna minor, Potamogeton crispus,
Vallisneria spiralis, Hydrilla verticillata,
Ipomoea reptans, Azolla pinnata, Spirodela
polyrhiza, Eleocharis plantaginea, Nymphaea
alba, Nymphaea rubra, Sagittaria sagittifolia,
Euryale ferox, etc. Euryale ferox , with edible
seeds, earn revenue for the government. Further,
18 genera of phytoplankton occur in the core area
of the Beel ecosystem. Of these, Oscillatoria and
Microcystis are abundant. Other plants along the
lake shore include Eupatorium odoratum ,
Achyranthes aspera , Cyperus esculentus ,
Phragmites karka , Vitex trifolia , Ocimum basilicum , Saccharum spontaneum and Imperata arundinacea. Dominant tree species in the deciduous
forests around the Beel are Tectona grandis ,
Ficus bengalensis , Shorea robusta, Bombax malabaricum , etc. Also, aquarium plants, medicinal
plants and orchids of ornamental and commercial
value are sometimes found.
Avi Fauna
Two hundred and thirty-two species of birds
(which include more than 70 migratory species)
are reported to occur in the Beel area. Sometimes,
19,000 waterbirds are counted in a single day.
Some of the globally threatened species are spotbilled pelican ( Pelecanus philippensis ), lesser
adjutant stork ( Leptoptilos javanicus ), baer’s
Plate 20.44 Deepor Beel
20.2 Wetlands of Northeast India (The Water Wealth of Northeast India)
Topography and Geology
The Beel is bounded by steep highlands on the
north and south. The Beel and its adjoining areas
were, perhaps, abandoned channels of the
Brahmaputra river system. The Beel soil represents recent alluvium consisting of clay, silt and
sand, while the highlands around the Beel are
made up of gneisses and schists of the Archaean
age.
Hydrometeorology
The climate is hot and humid under the infl uence
of tropical monsoon. The Beel is mainly fed by
the inlets, Basistha and Kalmani rivers and local
monsoon run-off between May and September.
The main outlet is the Khonajan channel, which
drains the Beel water into the Brahmaputra River.
It, thus, acts as a natural storm water reservoir
during the monsoon season for the Guwahati
City. Temperature in the Beel ranges from 9.3 to
38.4 °C. ‘Boro’ paddy is cultivated in the exposed
shoreline (up to about 1 km) of the Beel during
winter. Pre-monsoon showers occur generally
between March and May .
Flora
Eichhornia crassipes, Pistia stratiotes, Ottelia
alismoides, Lemna minor, Potamogeton crispus,
Vallisneria spiralis, Hydrilla verticillata,
Ipomoea reptans, Azolla pinnata, Spirodela
polyrhiza, Eleocharis plantaginea, Nymphaea
alba, Nymphaea rubra, Sagittaria sagittifolia,
Euryale ferox, etc. Euryale ferox , with edible
seeds, earn revenue for the government. Further,
18 genera of phytoplankton occur in the core area
of the Beel ecosystem. Of these, Oscillatoria and
Microcystis are abundant. Other plants along the
lake shore include Eupatorium odoratum ,
Achyranthes aspera , Cyperus esculentus ,
Phragmites karka , Vitex trifolia , Ocimum basilicum , Saccharum spontaneum and Imperata arundinacea. Dominant tree species in the deciduous
forests around the Beel are Tectona grandis ,
Ficus bengalensis , Shorea robusta, Bombax malabaricum , etc. Also, aquarium plants, medicinal
plants and orchids of ornamental and commercial
value are sometimes found.
Avi Fauna
Two hundred and thirty-two species of birds
(which include more than 70 migratory species)
are reported to occur in the Beel area. Sometimes,
19,000 waterbirds are counted in a single day.
Some of the globally threatened species are spotbilled pelican ( Pelecanus philippensis ), lesser
adjutant stork ( Leptoptilos javanicus ), baer’s
Plate 20.44 Deepor Beel
20.2 Wetlands of Northeast India (The Water Wealth of Northeast India)