Effects of Overpopulation on Resources

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Overpopulation
Impact on Resources
Effects of Overpopulation on
Resources
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Overpopulation can lead to the overuse and
degradation of resources
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Where?
Sahel, Africa.
(Includes parts of Sudan)
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Causes of Desertification
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Human activities; overgrazing, deforestation
(triggered by overpopulation)
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Climate change; drought
Areas affected by Desertification
Overgrazing
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Cattle are a sign of status
More people mean more cattle
Nomads graze more cattle on the land than it can
support
Reduces plant cover
Grasses often do not re-grow
Soil damaged
Infertile, unsuitable for crops
Deforestation
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Trees removed for fuel.
Trees removed to clear land for crops.
Less tress mean reduced transpiration of
moisture from them.
As a result the atmosphere contains less
moisture and there is less rainfall in the region.
Deforestation; Fuel
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Increase in population
High demand for fuel
Forest clearances
Soil exposed to wind and flash floods
Soil erosion
Animal manure may be used as fuel, thus
depriving the soil of fertiliser.
Over-cropping/Over- cultivation
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Pressure to grow cash crops
Cotton, beans, etc
Plantation workers get small tracts of land beside
plantations
To feed their families they grow crops here
continuously
Land cannot be left fallow
Soil loses its nutrients and becomes useless
Desertification
Climate change
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30% decrease in rainfall levels in the Sahel in
20 years.
Drought more frequent
Dry soil leads to soil erosion
Wells have been dug anywhere possible
This dries out the soil even more
Depletion of Resources
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