Desert or Great Indian Desert,
extensive region of sandy desert in northwestern
India and eastern Pakistan. The Thar Desert
covers an area of 44.6 million hectare (mha),
of which 27.8 mha lie in India and the rest
The desert is bounded by the Aravalli hills
in the east, by the fertile Indus and the
Nara valleys of Pakistan and the salt marsh
of the Rann of Kutch in the west, and by
the alluvial plains of Haryana and Punjab
in the north.
In India, most of the area of the Thar Desert
is situated in western Rajasthan. Of the
total area of the Thar, nearly 60 per cent
is being farmed, with varying intensities
of cropping, and 30 per cent is open pastureland.
The annual average rainfall is around 500
mm in the east to less than 100 mm in the
west and there is high variability from
year to year. Agriculture in the region
is extremely precarious and four out of
every 10 years on an average, are drought
years. Strong winds blow for four to five
months in a year over a large part of the
desert region. Dust storms during summer
are a common feature.
The region has great diversity
in vegetation. As many as 700 species
of plants are found in the area, of which
107 are of grass alone. These plants are
deep-rooted and tenacious enough to withstand
extended droughts and yet efficient enough
to gain biomass rapidly during a favourable
season. The local grasses are generally
prolific seeders, and most of the species
are palatable, fairly nutritious and rich
in minerals, including trace elements.
The Thar Desert is endowed with some of
the best breeds of livestock in the country.
Nearly 50 per cent of the country's wool
is produced in Rajasthan, and the area
has been the main supplier of bullocks
to the North.
By and large, land-use
in the Thar is dependent on rainfall.
In good rainfall years, large areas are
cropped, cattle thrive on extensive pastures
and substantial amounts of hay are stored
for future use. Rainwater is stored in
ponds and underground tanks. As rainfall
is very erratic, a pattern of mixed farming
has been developed in which human and
animal populations benefit from each other.