2. the thar desert also known as the great Indian
desert or marutsthali is a large ,arid region in
the north-western part of the Indian
subcontinent that forms a natural boundary
between India and Pakistan. It is the worldโs 9th
largest subtropical desert.
3. The Thar Desert extends between the Aravalli
Hills in the north-east, the Great Rann of Kutch
along the coast and the alluvial plains of the
Indus River in the west and north-west. Most
of the desert is covered by huge shifting sand
dunes that receive sediments from the alluvial
plains and the coast. The sand is highly mobile
due to strong winds occurring before the onset
of the monsoon. The Luni River is the only river
integrated into the desert.
4.
5. Stretches of sand in the desert are
interspersed by hillocks and sandy
and gravel plains. Due to the
diversified habitat and ecosystem,
the vegetation, human culture and
animal life in this arid region is very
rich in contrast to the other deserts
of the world. About 23 species of
6.
7. The region is a haven for 141 species of
migratory and resident birds of the desert. One
can see eagles, harriers, falcons, buzzards,
kestrel and vultures. There are short-toed
eagles (Circaetus gallicus), tawny eagles (Aquila
rapax), greater spotted eagles (Aquila clanga),
laggar falcons (Falco jugger) and kestrels. There
are also a number of reptiles.
The Indian peafowl is a resident breeder in the
Thar region. The peacock is designated as the
national bird of India and the provincial bird of
the Punjab (Pakistan). It can be seen sitting on
8. Vegetation
The natural vegetation of this dry
area is classed as Northwestern
thorn scrub forest occurring in
small clumps scattered more or
less openly. Density and size of
patches increase from west to
east following the increase in
rainfall. The natural vegetation of
9. Agriculture
The Thar is one of most heavily populated
desert areas in the world and the main
occupations of people living here are
agriculture and animal husbandry.
Agriculture is not a dependable proposition
in this areaโafter the rainy season, at
least 33% of crops fail. Animal husbandry,
trees and grasses, intercropped with
vegetables or fruit trees, is the most viable
model for arid, drought-prone regions. The
region faces frequent droughts.
10.
11. The Sahara is the largest subtropical
hot desert and third largest desert
after Antarctica and the Arctic. At over
9,400,000 square kilometers
(3,600,000 sq mi), it covers most of
North Africa, making it almost as large
as China or the United States. The
Sahara stretches from the Red Sea in
the east, including parts of the
Mediterranean, to the Atlantic Ocean in
12. The Sahara covers large parts of
Algeria, Chad, Egypt, Libya, Mali,
Mauritania, Morocco, Niger, Western
Sahara, Sudan and Tunisia, extends
over 9 million square kilometers
(3,500,000 sq mi) and it covers about
1โ4 of the African continent. If all
areas with a mean annual precipitation
of less than 250 mm were included,
13. The Sahara is a harsh environment with extreme conditions. It is the
world's largest subtropical hot desert, and the world's hottest desert.
The Sahara has mainly a subtropical, hot desert climate (Kipper climate
classification BWh) with long, prolonged, extremely hot to scorching
summers while the winters stay short, brief, extremely warm to truly
very hot. The climate of this desert is also characterized by a perpetual
clear sky, fair weather and by very low, and even almost non-existent
rainfall but the precipitation is also very irregular and sporadic.
Although the Sahara is located under the Tropic of Cancer in the most
part, this climate is said to be subtropical due to the subtropical high
pressure belt, which is mainly responsible of the hot desert climate.
14. The climate of the Sahara has undergone
enormous variations between wet and dry
over the last few hundred thousand
years. This is due to a 41,000 year cycle
in which the axial tilt of the earth
changes between 22ยฐ and 24.5ยฐ.At
present (2000 CE), the Sahara is in a dry
period, but it is expected that the
Sahara will become green again in 15,000
years (17,000 CE).
15.
16. The Flora of the Sahara is highly diversified based on
the bio-geographical characteristics of this vast
desert. Floristically, the Sahara has three zones based
on the amount of rainfall received โ the Northern
(Mediterranean), Central and Southern Zones. There
are two transitional zones โ the Mediterranean-Sahara
transition and the Sahel transition zone.
The Saharan flora comprises around 2800 species of
vascular plants. Approximately a quarter of these are
endemic. About half of these species are common to
the flora of the Arabian deserts.
17.
18. Several species of fox live in the Sahara,
including the fennec fox, pale fox and Rรผppell's
fox. The addax, a large white antelope, can go
nearly a year in the desert without drinking. The
dorcas gazelle is a north African gazelle that
can also go for a long time without water. Other
notable gazelles include the Rhim gazelle and
dama gazelle.
The Saharan cheetah (northwest African
cheetah) lives in Algeria, Togo, Niger, Mali,
Benin, and Burkina Faso. There remain fewer
than 250 mature cheetahs which are very
