Savanna - Tartu Veeriku Kool

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World Biomes
Savannah
Distribution of biome
• 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.
Distribution
Climate
• A tropical wet and dry climate predominates in
areas covered by savanna growth. Mean
monthly temperatures are at or above 18° C
and annual precipitation averages between
750 and 1300 mm. For at least five months of
the year, during the dry season, less than 10
mm a month are received. The dry season is
associated with the low sun period.
Soil
• Soils vary according to bedrock. In general,
low fertility soils can be expected.
Plants I
• 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 of during the winter to
conserve water.
Plants II
• 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 savannah also have
storage organs like bulbs and corms for
making it through the dry season.
Baobab
Elephant Grass
Umbrella Thorn Acacia
Candelabre tree
Animals I
• 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.
Animals II
• Different plant eaters provide a wide range of
food for meat eaters, like lions, leopards,
cheetahs, jackals and hyenas. Each species
has its own preference, making it possible to
live side by side and not be in competition for
food.
African Elephant
Lion
Zebra
Hyena
Emu
Red kangaroo
Black Mamba
Nile Crocodile
Termite mound
Aardvark
People I
People II
Grain sorghums are the
staple food for millions
of people in China,
India, and Africa. It is
the most drought
tolerant grain crop.
People III
Millet is a crop of
vital importance to
millions of African
families living in
semi-arid regions of
the continent. Millet
is one of the world’s
most resilient crops.
In many areas where
millet is the staple
food, nothing else
will grow.
People IV
• Desertification is the process which turns
productive into non- productive desert as a
result of poor land-management.
Desertification occurs mainly in semi-arid
areas (average annual rainfall less than 600
mm) bordering on deserts.
• Overgrazing is the major cause of
desertification worldwide.
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