lR;eso t;rs - Ministry of Environment and Forests

join in Bangladesh, and continue to flow as River Padma or
Ganga. The Brahmaputra rises in Tibet, where it is known as
Tsangpo and runs a long distance till it crosses over into India in
Arunachal Pradesh under the name of Dihang. Near Passighat,
Debang and Lohit join river Brahmaputra and together run all
along Assam in a narrow valley. It crosses Bangladesh as a
downstream of Dhubri.
In the Deccan region, most of the major river systems flow in the
eastern direction and fall into the Bay of Bengal. The major Eastflowing
rivers are Godavari, Krishna, Cauvery and Mahanadi.
Narmada and Tapti are the major West-flowing rivers.
River Godavari in the Southern peninsula forms the second
largest river basin, covering ten per cent of the total area of the
country, while the Mahanadi has the third largest basin. River
basin of the Narmada in the uplands of the Deccan, flowing into
the Arabian Sea, and of Cauvery in the south, falling into the Bay
of Bengal is about the same size, though with different character
and shape.
There are numerous coastal rivers, which are comparatively
smaller. While only a handful of such rivers drain into the sea
along the East Coast, there are as many as 600 such rivers on the
West Coast.
CLIMATE
The climate of India may be broadly described as tropical
monsoonal type. There are four seasons:
Swamp Deer in their natural habitat
4
State Of Environment Report-2009
(i) Winter (January-February)
(ii) Hot weather summer (March-May)
(iii) Rainy South-Western monsoon (June-September) and
(iv) Post-monsoon, also known as North-East monsoon in the
southern Peninsula (October-December)
India's climate is affected by two seasonal winds - the North-East
monsoon and the South-West monsoon. The North-East
monsoon, commonly known as the winter monsoon blows from
land to sea, whereas the South-West monsoon, known as the
summer monsoon blows from sea to land after crossing the
Indian Ocean, the Arabian Sea, and the Bay of Bengal. The
South-West monsoon brings most of the rainfall during a year in
the country.
BIODIVERSITY
India, a megadiverse country with only 2.4 per cent of the land
area, accounts for 7-8 per cent of the recorded species of the
world, including over 45,500 species of plants and 91,000
species of animals.
India is situated at the tri-junction of the Afro-tropical, the Indo-
Malayan and the Paleo-Arctic realms, which display significant
biodiversity. Being one of the 17 identified megadiverse
countries, it is home to 8.58 per cent of mammalians, 13.66 per
cent of avians, 7.91 per cent of reptilians, 4.66 per cent of
amphibians, 11.72 per cent of fish, and 11.80 per cent of plant
species documented so far.