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A home to many
animals, the Australian tropical savanna is one of the
world's largest tropical savannas. The world's other
savannas cover two fifths of Africa and large amounts of
India and South America. The Australian tropical savanna is
an area of dense grass and scattered trees that stretches
across northern Australia from Broome to
Townsville. A savanna is usually
very flat and with few trees and shrubs, this is because the
fires destroy most of the trees and shrubs which usually
aren't fire resistant. This happens frequently during the
summer. This is also because savannas across the world have
a limited water supply and bigger vegetation such as trees
are the first to die out. Most savannas are near the
equator, but the Australian savanna is south of the equator,
which causes this region to have summer while we are having
fall. Savannas usually occur only in a climate that has both
a rainy and dry season. Each of these different seasons is
very extreme. The dry seasons, or
"the dry", of the Australian savanna can last up to five
months, from May to October. With each dry season come
forest fires. These forest fires occur often, and
geographers believe that fire keeps the savanna healthy. The
tropical rain forest trees, that would have otherwise grown
in that climate, don't grow because they are destroyed by
the fires. Though the fires don't destroy all of the
underground grasses, the fires limit the growth of any
vegetation that isn't fire resistant. Usually the
temperatures are cooler, with clear skies and low
humidity. During this time,
water is key. The rainy season, or "the wet", can be pretty
bad too. Some savannas around the world get ten inches of
rain, and some ten full feet. Some pools, ponds, lakes,
rivers, and streams flood. Much of the Australian savanna
rain falls in heavy bursts of thunderstorms and monsoons.
During the wet, which lasts from December to March, it is
hot and humid. Temperatures can get as high as 50°C but
usually stays around 30s (°C). Marsupials dominate
among the animals in this area of Australia. Marsupial's are
mammals whose young are born undeveloped. The premature
marsupial baby spends most of its growing up attached to the
mother's nipple in a pouch. Marsupials are different from
other mammals because they give birth to such undeveloped
offspring while other mammal's young are much more mature.
The animals include the Echidna, Eastern Gray Kangaroo, the
Koala Agile and Whiptale Wallabies, Walaroos, Possums,
Gliders, the Northern Qoull, and the Golden Bandicoot. These
animals live in or near the few trees in this area for
shade, food, and water. In the other parts of the tropical
savanna, the reptiles dominate. The saltwater Crocodile,
which is found here, is the world's largest reptile. It can
grow to be from 7 to 8 meters long. The vegetation in
Australia differs from that of other Savannas. The acacia,
part of the 1,200 members of the pea family, is the most
common tree in other savannas. The acacia tree does grow in
Australia but only in tropical and subtropical areas so,
it's not the most common. Acacia's produce a gum called gum
arabic, this is used in drugs, foods and others. The
acacia's flowers are yellow or white and they grow in
bundles. The most common tree
in Australia is the eucalyptus. They are famous for their
oil, gum, and timber. The eucalyptus grows in warm climates
and they are the most important tree for timber in
Australia. The bark of some of these trees furnishes tannin,
which is used in medicine. There are many
threats to this biome. The foreign pests and weeds that have
been brought to this biome, such as the wetland weed Mimosa,
threaten the survival of the region's ecosystems and native
species. The Australian government has sponsored programs to
clear away brush for agricultural reasons. When some of the
farmers took over land, they brought with them new systems
that caused some species to become endangered. The
Aboriginal people have been stripped of their homes so that
the government can make more room for agriculture. The World
Wildlife Fund (WWF) in Australia is reacting to this
destruction by working with the communities to stop the
clearing programs. This savanna is
unique in many ways, including its climate, its animals, its
vegetation, and its beauty. It's not quite like the other
savannas of the world. It provides a home for the animals we
don't have anywhere else in the world. Its vegetation is
unique too. The area of the world it is in makes its climate
extremely different from the others around the world. The
entire planet would suffer greatly if we destroyed this
biome. Thanks to the WWF,
this ecosystem may survive. Without such intervention, this
world's savannas won't stand a chance. by Alix C.
2001.
bibliography: Strahler, Arthur N.
"Australian Savanna", Elements of Physical Geography,
3rd Edition "Savanna" The
World Book Multimedia Encyclopedia. 2000 ed. "Tropical Savanna",
http://www.wwf.org.au/tsavanna.htm
(31 October, 2000) "Reptiles give new
slant on conservation", http://savanna.ntu.edu.au/publications/savanna_links5/reptile.
html "Savanna Guides -
About Tropical Savannahs",
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