Brahamaputra Basin

Brahamaputra Basin
• Gullied and ravenous waste lands are found associated with stream courses of the
Brahmaputra and its major tributaries.
f) Waterbodies: Approx. 6 % of the basin is covered by river and waterbodies.
• The river Brahmaputra and its tributaries have the major contribution to this land cover
class.
• Lots of wetlands (lakes) and oxbow lakes of considerable size are spotted in the
Brahmaputra valley region.
g) Snow: The high elevated upper mountainous portion of Arunachal Pradesh and Sikkim is under
the Snow/Glaciers cover accounting 1.6 % of the basin.
The statistics of LEVEL-I landuse/land cover classification of the Brahmaputra basin is shown below
in the Table.4.
1.6 Soils
Table 5. Land use/ Land cover statistics (2005-06)
Sl.No Category Area (Sq. km) % of Total Area
1 Built Up Land 3162.58 1.63
2 Agricultural 50374.57 25.91
3 Forest 107854.27 55.48
4 Grassland 8531.46 4.39
5 Wasteland 10117.28 5.20
6 Waterbodies 11265.77 5.79
7 Snow / Glaciers 3107.07 1.60
Source: India-WRIS
The most predominant soil type found in the basin is the red loamy soil and alluvial soil. Other
important soil types are sandy, loamy, clayey soils, their combinations and laterite soils. The alluvium
derived soils of the Brahmaputra valley have been grouped into new and old alluvium and forest
soils. The upland soils are more developed due to the origin of the alluvium in Pleistocene age,
whereas other soils are less developed due to their origin on younger alluvium.
The available information on soil survey conducted in the basin indicates that red loamy soils are
predominant in the Kameng, Subansiri, Siang, Lohit and Tirap districts of Arunachal Pradesh. Few
places with alluvial and laterite soil is also reported in this region. The Mokokchung, Tuensang and
Kohima region of Nagaland is predominated by red Loam, loams to fairly heavy clay soils.The
Brahmaputra valley of Assam is predominated by the new alluvium soil, sandy to clay loamy soil.In
the North Cachar and Mikir hills red loam and laterial soil is found. The principal soil types of Garo,
Jaintia and Khasi Hills of Meghalaya are Laterite, new alluvium, heavy clay, loamy silt and fine
silt.Koch Behar region of West Bengal is predominated by Alluvium, sand, light loam and black loam.
Soil type of Jalpaiguri and Darjeeling is basically Terai (alluvium of sandy loam) soils.
The cultivable area of the sub-basin is about 12.15 M. ha which is 6.2 % of the culturable area of the
country.
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