The Savanna of Africa

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The Savanna of Africa

• Can you trace it on a map?

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What is a savanna?

• A savanna is a rolling grassland scattered with
  shrubs and isolated trees, which can be found
  between a tropical rainforest and desert biome.
• Not enough rain falls on a
• savanna to support forests.
• Savannas are also known as tropical grasslands.
• They are found in a wide band on either side of
  the equator on the edges of tropical rainforests.

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Climate on the Savanna

• Savannas have warm temperature year round.
• There are actually two very different seasons in
  a savanna a very long dry season (winter), and a
  very wet season (summer).
• In the dry season only an average of about 4
  inches of rain falls. Between December and
  February no rain will fall at all. Oddly enough,
  it is actually a little cooler during this dry
  season. But don't expect sweater weather it is
  still around 70 F.

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Summertime and the living is rainy

• In the summer there is lots of rain.
• In Africa the monsoon rains begin in May. An
  average of 15 to 25 inches of rain falls during
  this time.
• It gets hot and very humid during the rainy
  season. Every day the hot, humid air rises off
  the ground and collides with cooler air above and
  turns into rain.
• In the afternoons on the summer savanna the rains
  pour down for hours. African savannas have large
  herds of grazing and browsing hoofed animals.
  Each animal has a specialized eating habit that
  reduces competition for food.

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Plant life of the Savanna

• Plants of the savannas are highly specialized to
  grow in this environment of long periods of
  drought.
• They have long tap roots that can reach the deep
  water table, thick bark to resist annual fires,
  trunks that can store water, and leaves that drop
  off during the winter to conserve water.
• The grasses have adaptations that discourage
  animals from grazing on them some grasses are
  too sharp or bitter tasting for some animals, but
  not others, to eat.
• The side benefit of this is that every species of
  animal has something to eat. Different species
  will also eat different parts of the grass. Many
  grasses grow from the bottom up, so that the
  growth tissue doesn't get damaged by grazers.
• Many plants of the savanna also have storage
  organs like bulbs and corms for making it though
  the dry season.
• Baobab trees are found in Africa.

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Wildlife on the savanna

• The savannas we are most familiar with are the
  East African savannas covered with acacia trees.
• The Serengeti Plains of Tanzania are some of the
  most well known. Here animals like lions, zebras,
  elephants, and giraffes and many types of
  ungulates (animals with hooves) graze and hunt.
• Many large grass-eating mammals (herbivores) can
  survive here because they can move around and eat
  the plentiful grasses.
• There are also lots of carnivores (meat eaters)
  who eat them in turn.

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More animal info.

• Most of the animals on the savanna have long legs
  or wings to be able to go on long migrations.
• Many burrow under ground to avoid the heat or
  raise their young.
• The savanna is a perfect place for birds of prey
  like hawks and buzzards. The wide, open plain
  provides them with a clear view of their prey,
  hot air updrafts keep them soaring, and there is
  the occasional tree to rest on or nest in.
• Animals don't sweat to lose body heat, so they
  lose it through panting or through large areas of
  exposed skin, or ears, like those of the elephant.

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People

• How do the people of the savanna live?
• Think about What they do as work
• How do they travel?
• Where and how do they live?

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Living in the Savanna

• Farming and herding are the major ways of living.
• Permanent settlement is limited by the long dry
  season, uncertain rainfall, and poor soils.
• Overgrazing and cultivation of marginal soils
  already low in plant nutrients are destroying
  what were once rich farming lands..

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Slash and Burn

• In the savannas, trees are cut down over a large
  area and then stacked on fields, where they are
  burned. The wood ash adds fertilizer to the soil.
  
• Crops like sorghum, millet, and cassava are grown
  for several years, until the soil is exhausted.
  Then the farmers must move on.

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Herding

• In places where cattle are raised, fertilizer is
  used to prolong the fertility of the soil, but
  pests (Tsetse fly), disease, and drought cause
  many problems.
• Many farmers and herders are moving from the
  savannahs towards the South to port cities in
  search of work.

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Info taken from

• http//www.blueplanetbiomes.org/savanna.htm