Brahamaputra Basin

Brahamaputra Basin
1.5 Land use/land cover
Land cover is the physical coverage on earth system i.e. forest, natural waterbodies etc.whereas land
use is anthropogenic in sense that how people use that land.
The commonly observed components of the land surface of the Brahmaputra basin are the forest
cover, crop fields, grazing land, tea plantations, and water logged swampy areas/wetlands with a
huge network of tributaries. The landuse/ land cover map of Brahmaputra basin is shown in Map
5.depicting the landuse/ land cover scenario of the basin for the year 2005-06; mapped using the IRS
Resourcesat-1, LISS III satellite data. The important landuse classes of this basin are:
a) Builtup: Builtup land covers 1.63 % of the basin. Majority of the builtup areas are rural
settlement. Few mining areas are also spotted.
b) Crop/ Agricultural land: Agricultural land (both standing crop + present fallow) accounts 25.91
% of the total area. Agriculture is basically rainfed.
• The Kharif Rice crop is the predominant crop in the basin. Most of the agriculture fields
found lying in the plain areas of Assam, Meghalaya and West Bengal.
• Riverbed cultivation in the large ‘Char’/Island areas of Brahmaputra River is also
observed along whole course of the river in the lowland.
• Jhum/ Shifting cultivation is the main form of agriculture in the hills and foot hill regions
of the basin practised in varied scale covering 0.69 % area of the basin.
• Large patches of Tea gardens observedmost commonly in the Upper Assam part
(Dibrugarh, Tinsukia, Sibsagar, Golaghar, and Tezpur), Cachar, Silchar, Jalpaiguri and
Darjeling region.This class covers 2.48 % of the total basin area.
c) Forest: The major part of basin is covered with forest accounting to 55.48 % of the total area.
• Most common vegetation of Brahmaputra valley and the low elevation adjoining hills is
the‘deciduous forest’accounting 23.32 % of the basin.
• Evergreen forests in this basin include both coniferous and tropical broad leaved
evergreen species. Semi evergreen forest includes a combination of evergreen and
deciduous species with the former dominating the canopy.This broad class ‘evergreen
and semi-evergreen’forest type is found in the hilly districts of Arunachal Pradesh,
Sikkim, in the frontier districts of Assam (Lakhimpur, Sibsagar and Cachar) in a more or
less continuous narrow belt along the foot of the Himalayas, covering 33.30 % of the
Basin.
• ‘Scrub forest’ in the basin found located on hill/ mountain slopes and some places at
the fringes of dense forest cover.
• Few patches of the forest plantation are also observed.
d) Grass/grazing lands: Grasslands are also commonly observed accounting 4.39 % of the basin.
• Short grass/grazing landfound close to river/ stream, swampy wetlands and hilly slopes.
• The alpine grass/grazing lands are observedin the highaltitude Himalayan range of
Arunachal Pradesh and Sikkim between the evergreen forest and permanent snow
covered areas.
e) Wasteland: Wasteland class covers 5.20 % of the basin.
• Large cover of Scrub lands are observed in the moderate slopes in the plain and foot hills of
Tawang, East & West Kameng, Karbi Anglong and the North Cachar hills district of the basin.
• Few barren, rocky wasteland regions are also observed in the basin.
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