Desertification:
is the process by which
land becomes desert
Case study: the Sahel
• The Sahel is
becoming more like
desert with thin, dry,
sandy soils
• Soil erosion has
created bare rock
• Vegetation is sparse
The UN environment programme
took up combating desertification as
a major part of its work.
In the 1990s it argued that
desertification threatened nearly a
quarter of the Earth’s land surface.
How have each of these factors
contributed to desertification?
desertification
climate
humans
animals
Climate
•
Drought: low rainfall since 1968.
•
Soils become dry and there is
no water left in wells.
•
Trees die, grass withers and is
replaced by poor desert scrub.
•
Crops fail and cattle feed on
poor pasture.
•
Less roots to protect the
topsoil, less humus; soils
become more sandy and dry.
•
Wind erosion removes the soil,
causing dust storms, leaving
bare rock.
Human activity
•
Population is high and
increasing fast.
•
To increase food supplies more
crops are grown and more
cattle kept leading to overcultivation and over-grazing.
•
Yields decline and cattle are
undernourished and die.
•
Demand increases for water as
population grows.
•
Trees are cut down for fuel
supplies.
•
Less vegetation; more dry, bare
soil; more wind erosion.
Animals/insects
• Locusts destroy the crops.
• Overgrazing means all
vegetation is eaten.
• Animals trample the ground
reducing it to dust.
• Animals die and can’t breed.
What are the effects of
desertification?
Starvation
• Food and water
shortages lead to
malnutrition, famine,
disease and high
death rates.
Aid Programmes
Large numbers of
people become
dependent on
food aid
programmes.
Migration
• From rural to urban
areas causing overpopulation in towns.
• To refugee camps.
Solutions?
How can we solve the
problems of desertification?
Solutions
• In the short-term, provide food aid and water supplies to
prevent suffering.
• Improve water supplies by building large reservoirs and drilling
deeper wells.
• Conserve water in local small-scale schemes eg ‘magic stones’
in Burkino Faso.
• Encourage sustainable farming practices (using locally-made
tools, not tractors).
• Provide drought-resistant seed such as millet (northern
Nigeria). GM crops.
• Tree planting schemes to reduce soil erosion (Mauritania).
• International action to reduce the causes of global warming.
Solving the Problems: the results
Nov 1992
Nov 1998
Before and after
animals have
overgrazed and
trampled the
savanna.
Solving the Problems: the results
Before
After
Which scheme do
you think solved
these problems?
Conservation Projects
Eden Foundation
Founded 1985 in Sweden
•
•
•
•
•
Niger is one of the driest countries in
the world, situated south of the Sahara
desert. The people are poor and have
neither money nor water to spare.
Their solution is to bring trees and
bushes that can grow naturally in this
dry area and give food, even in times
of need.
There are 250,000 known plant
species in the world, but only 20 of
them provide 90% of our food so the
Eden Foundation grow underexploited,
edible trees and bushes to feed the
local people.
Since their arrival, Eden has served
more than 2500 households in the
region.
The seeds are free and they show the
local people how to grow the seed.
They also give health advice.
Eden Foundation
"Thanks to our Eden trees, we've
had food to eat even though the
millet failed. For the last three
years, we haven't had a single
good rain in our village and this
year's harvest lasted less than a
month. Instead, my family has
lived from the Eden fruits on our
field which gives us food for the
day. We depend on it, for there is
nothing else to eat around here."
- Musa Abari from Garin Farara
Charity Events
Band Aid:
20th Anniversary raising
money for the victims of
famine and starvation.
Trying to cancel ‘Third
world’ debt.
Midge Ure and Sir Bob Goldolf
Problems?
• Civil wars, as in
Ethiopia and Sudan
prevent aid reaching
stricken areas and
cause mass
migration to refugee
camps.
• Population growth
continues to
outstrip food
supplies.