Download Africa: the Plateau Continent

Africa:
the Plateau Continent
The physical geography of
Africa
Vocabulary
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Basin
Nile River
Rift Valley
Mount Kilimanjaro
Escarpment
Plateau
• plateau
– covers most of Africa.
– narrow strip of coastline.
• Throughout the plateau there are several basins.
– Basins – depressions where river systems usually drain.
• Imagine a bowl
5
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625 + miles across
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t
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p
Why is there no
basin here?
Notice the
plateau outline.
The Congo
Basin
•The Congo Basin
•second largest tropical forest,
•700,000 square miles in six countries,
•quarter of the world’s remaining tropical forest.
•over 10,000 species of plants,
•1,000 species of birds,
•400 species of mammals.
•24 million people,
•depend on the forest for their livelihoods.
Rivers
• Since water travels downhill flows into, and
through basins.
– Basins contain giant (size of Texas) swamps
• Lots of water-borne diseases
• As the rivers cut through the edge of basins
toward the sea, they fall over the edge of the
plateaus in a series of waterfalls and rapids
through narrow gorges.
– not useful for navigation because of these
cataracts
The origin of the Nile, where it leaves Lake Victoria and begins its journey northward.
A cataract is
a part of the
river that is
impassable to
ships.
Distinctive African Landforms
• Rift valley – a long thin valley created by the
splitting of the continental plates.
Photo of the Great Rift Valley from the International Space Station
The volcanoes are at the edges of
the plates.
When do you expect Africa to
be ripped completely apart?
What do the red
triangles represent?
Mountains
• Mount Kilimanjaro– Africa’s highest mountain.
– volcanic
• Escarpment – a steep slope with a nearly
flat plateau on top.
• The Great Escarpment
• Southern edge of the continent
Ol Doinyo Lengai volcano,
Tanzania
Minerals and Resources
• Africa produces
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80% of the world’s platinum
30% of the world’s gold
42% of the world’s cobalt
Much of the worlds oil is located in North Africa
• Africa possesses a huge amount of the world’s
minerals
• Why are they still so poor?
Africa in the Early Twentieth Century
Minerals attract others
• Europeans
colonized Africa
in late 1800s.
• Shipped riches
back to Europe
• Left Africa
poorer
Resources
• Oil and Coffee are the most profitable
commodities in Africa.
– Commodity is something that can be sold (specifically
agricultural or mining)
• Lumber is another important commodity.
• 66% of Africans earn their living from farming.
• Subsistence agriculture is the single most important
economic activity in Africa.
Africa: A Land of Extremes
Climate and Vegetation
Deserts
• Sahara-largest desert in the
world
– 3000 miles from Atlantic to
Red Sea
– 20% sand (erg)
– 80% rock formations, gravelly
plains (reg)
– 136° to below freezing
• Kalahari Desert in the south
• Namib Desert in the
southwest
• Aquifers-underground
water
• Oasis-where water comes
to the surface
Tropics
• Between the Tropic of
Cancer and the Tropic
of Capricorn
• No noticeable
difference between
seasons
• Day length equals night
(12 hours day, 12 night)
• 90% of Africa is in the
tropics
• Cooler at night
Rainforest
• Congo Basin
• Madagascar
– Nearly destroyed
through slash and
burn farming
• Canopy
– Uppermost layer of
branches
– 150 feet above the
forest floor
Sunshine and Rainfall
• Congo Basin
rainforest receives
rain year round
• The rest of the
continent has
either no rain or
two seasons – wet
and dry
Tropical Grassland
• Serengeti Plain
– Northern Tanzania
– Hard soil and dry
climate prevent
trees but are good
for grass
– Lots of animals
(think Lion King)
Africa:
Human
Environment
Interaction
Desertification of the Sahel
Desertification
– An expansion of
dry conditions into
moist areas next
to deserts
Before
After
Causes of Desertification
• Human factors
– Over grazing of livestock exposes soil
– Animals trample soil
– Farming
– Increased population
Result of Desertification
Loss of grasslands and farm areas
Stopping Desertification
• Very difficult to slow
this process
– Tree planting
– More efficient use of
farm and forest lands
To fight soil erosion of the land during
the dry season, these women in Burkina
Faso prepare the ground by pounding it
and terracing it in order to catch the
water when the rains finally come.
UN Photo #167616 by J. Isaac
Harming the Environment
in Nigeria
• Oil discovered here in
1956
• 80-90% of national
income
• Most of it purchased by
U.S.
• High oil prices in 1970’s
made Nigeria one of
wealthiest nations in
Africa
So, why are they poor now?
• Government mismanagement and corruption
• Poor planning
• Decline in oil prices
Destroying the Land and People
• 4,000 oil spills in the
Niger Delta in the
past 4 decades
• Slow & non-existent
clean-up
• Fires resulting from
spills have caused
acid rain, massive
deposits of soot
• Increased
respiratory diseases
This type of oil spill is
widespread in the Niger Delta.
Amukpe is near a major city of
Sapele and therefore attracted
attention of the public. In rural
areas, such spills would go on
for months before any action is
taken. The Federal Government
of Nigeria owned the facilities
from which oil gushed into River
Ethiope. Note the immediate
impact of the spill on plants.
The spill's impact on fish life
was probably tremendous. But
it remains unmeasured.
"PPMC's ruptured pipeline empting P.M.S.
(Premium Motor Spirit) into Okpe river for
over one month. Amukpe community,
Sapele L.G.A., Delta State, Nigeria."
Pipeline Exploitation
• “Bandits” and corrupt
government officials (is
there a difference?)
drain the pipelines and
resell the oil
• Villagers collect spilled
oil in small cans and
resell it
Oil emptied
into the Okpe
River just
above the
Niger Delta for
a month before
any effort was
made to stop it.
This spill only
took 1 month
to stop
because it took
place in a
larger
A man washed soot from his face in Lagos, Nigeria, after a
community gas pipeline ruptured by thieves exploded. At least 260
people were killed in the blast, which spewed fire and black
smoke. It was the latest oil-industry disaster in Nigeria,
Africa’s largest petroleum producer.
December 27, 2006
Nile River
Controlling the Nile
• Aswan High Dam
was built in 1970
with Russian
help.
• Created Lake
Nassar
Problems With the Dam
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Relocation of people; altering of traditional lifestyles
Removal of ancient artifacts and cultural treasures
Loss of ancient artifacts (now at the bottom of Lake Nasser)
Decreased soil fertility
Loss of silt deposits
Use of chemical fertilizers
Increased rates of malaria
Satellite image
of the dam