Brahamaputra Basin

Brahamaputra Basin
b) Assam - Dispur, northern Cachar hills and Karbi Anglong districts.
c) Meghalaya - Eastern and western garo Hills, Jaintia Hills and eastern and western Khasi
hills.
d) Nagaland -Kohima, Mon, Mokokchung, Phek, Tuensang, Wokha and Zunheboto districts
The agro-climate of the region is characterised by warm summers and cool winters. The mean
annual precipitation varies from 2000 to 3000 mm which exceeds the PET demand in most of the
months in a year, excepting the period of seasonal deficit. Length of growing period > 270 days.The
area represents Udic soil moisture regime. The soil temperature regime varies from Hyperthermic in
valleys to Thermic in higher topographic positions.The major soil formations in the area include
shallow to deep, loamy, red and lateritic and red and yellow soils.The natural vegetation comprises
wet evergreen and tropical moist deciduous forests. Jhum cultivation is common.Other major crops
cultivated in this region are Rice, millets, potato, maize and sesame. Hilly terraces are used for
plantation crops, such as tea, coffee, rubber and horticulture crops, like oranges, pineapple, etc.
ii) Hot subhumid (moist) to humid (inclusion of perhumid) eco-regions with alluvial-derived soils
(Agro-ecoregion - 15): Physiologically these agro-ecoregion comprising the plains pf the
Brahmaputra River, covering parts of the States of Assam and West Bengal including the
southern pockets of assam. States and districts under this ecoregion area.
Assam - Cachar (Silchar), Darrang, Dibrugarh, Dhubri, Golaghat, Goalpara, Jorhat,
Kamrup, Karimganj, non-tarai parts of Kokrajhar, Barpeta and Nalbari, Lakhimpur
(north), Nalbari, Sibsagar and Sonitpur districs.
b. West Bengal - Jalpaiguri (non-Tarai parts), Kochbehar.
The climate of the area is characterised by hot summers and mild to moderately cool winters. The
mean annual rainfall ranges from 1400-2000 mm, potential evapotranspiration is 1000–1400 mm.
The length of growing period (LPG) > 210 days. The soil moisture and temperature regimes are udicustic
(to Udic) and Hyperthermis, respectively. The common soil-scapes of the area are represented
by level to very gently sloping Haplaquepts, Haplaqualfs, Dystrochrepts, Eutrochrepts, Fluvaquents,
and Hapludalfs.The natural vegetation comprises tropical moist and dry deciduous forests. In view of
the high rainfall, the cropping system is rice based. The main crops of rainy season (Kharif) grown
under rainfed condition are rice and jute.In northern foothills of eastern Himalayas, plantation crops,
such as tea and horticultural cropslike pineapple, citrus and banana are grown under favourable
climatic conditions. Rice, jute, pulses, oilseeds (mustard) are grown on storesd/residual soil moisture
in Rabi season.
iii) Warm perhumid ecoregion with red and lateritic soils (Agro-ecoregion - 16): Physiologically
the eastern Himalayan agro-ecoregion encompasses northern hilly parts of West Bengal,
northern parts of Assam, Arunachal Pradesh and Sikkim states. The region occupies an area of
9.6 M. ha, represensting 2.9% of the total geographical area of the country. States and Districts
under this ecoregion area)
Arunachal Pradesh - Dibang Valley, eastern and western parts of Kameng, Lohit, easten
Siang, western Siang, lower and upper subansiri districts.
b) Assam -Tarai parts of Barpeta, Darrang, Kokrajhar and Nalbari districts.
c) Sikkim - Eastern and western parts of Sikkim.
d) West Bengal - Darjeeling and Tarai part of Jalpaiguri districts.
www.india-wris.nrsc.gov.in
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