Soil Problems in Africa

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Soil Problems in Africa

• Eric Battisti ESS 315

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Initial Soil Problems

• Tropical regions in general have less fertile
  soil compared to temperate regions
• Geologic parent material is lacking in essential
  minerals
• High temperatures accelerate chemical weathering
• Humid areas suffer from high acidity and toxic
  levels of aluminum and iron
• Most arable soils are coarse, without enough clay
  to absorb and hold moisture

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Latosols (the original presentation)

• Laterite is reddish to yellow brown iron rich,
  humus-poor soil that hardens irreversibly when
  dried and exposed to air
• Latosols are low in MgO, Sulfates, Nitrogen and
  Phosophorus
• Latosols are found in or near the surface of 15
  of sub-Saharan West African Soils, the highest
  concentration of latosols anywhere in the world
• The process of turning Latosols into arable land
  requires extensive treatments to reduce acidity
  and trace metals

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And on top of that

• Rampant deforestation
• Overgrazing
• Irresponsible irrigation practices
• Lure of cash crops

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Farming and Famine

• Currently 75 of Africas farmlands are severely
  degraded
• Africa looses an estimated 4 Billion of soil
  nutrients a year
• Fertilizer use is lowest in the world
• 85 of African farmland looses nutrients an
  annual rate of 30 kilograms per hectare

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Growth Expectations

• Increase in urbanization as countries develop
  facilitates erosion
• By 2020 continued erosion could lead to an
  estimated drop of 17-30 in crop yields
• Increases in population would lead to an increase
  in imported grain from 43 million tons to 60
  million tons

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Quick Fixes?

• Availability of appropriate fertilizers to
  African farmers
• Global awareness of the problem (dirt isnt media
  friendly)
• Improve tilling techniques and crop rotation
• Stop clearing of new land for farming and
  replenish dead soil with nutrients

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References

• http//www.globalchange.umich.edu/globalchange2/cu
  rrent/lectures/land_deg/land_deg.html
• http//home.windstream.net/bsundquist1/se3.htmlDc
  3
• http//edro.files.wordpress.com/2008/02/once-a-for
  est.jpg
• http//forests.org/archive/africa/afsickea.htm
• http//www.newscientist.com/article/dn8929-soil-he
  alth-crisis-threatens-africas-food-supply.html