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Grazing in the Sahel and Soil degradation

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Grazing in the Sahel and Soil degradation

  1. 1. Topic 3.4: Soil System Topic 3.5: Food Resources Grazing and Soil degradation Farming and Desertification
  2. 2. Topic 3.4: Soil System Topic 3.5: Food Resources Grazing and Soil degradation The Story of the Sahel
  3. 3. Topic 3.4: Soil System Topic 3.5: Food Resources Grazing and Soil degradation The Story of the Sahel • A Region in North Africa between 12 - 18˚N
  4. 4. Topic 3.4: Soil System Topic 3.5: Food Resources Grazing and Soil degradation The Story of the Sahel • A Region in North Africa between 12 - 18˚N • Defined by climate as a transitional zone between the Sahara to the north and more equatorial areas to the south
  5. 5. Topic 3.4: Soil System Topic 3.5: Food Resources Grazing and Soil degradation The Story of the Sahel • A Region in North Africa between 12 - 18˚N • Defined by climate as a transitional zone between the Sahara to the north and more equatorial areas to the south • Drought is common
  6. 6. Topic 3.4: Soil System Topic 3.5: Food Resources Grazing and Soil degradation The Story of the Sahel
  7. 7. Topic 3.4: Soil System Topic 3.5: Food Resources Grazing and Soil degradation The Story of the Sahel Photograph copyright Ewan Robinson
  8. 8. Topic 3.4: Soil System Topic 3.5: Food Resources Grazing and Soil degradation The Story of the Sahel • For the last 5000 years the Sahel region has experienced periods of higher rainfall followed by dryer periods roughly every 1000 years Photograph copyright Ewan Robinson
  9. 9. Topic 3.4: Soil System Topic 3.5: Food Resources Grazing and Soil degradation The Story of the Sahel • For the last 5000 years the Sahel region has experienced periods of higher rainfall followed by dryer periods roughly every 1000 years • 1950’s to early 1970’s saw above average rainfall Photograph copyright Ewan Robinson
  10. 10. Topic 3.4: Soil System Topic 3.5: Food Resources Grazing and Soil degradation The Story of the Sahel • For the last 5000 years the Sahel region has experienced periods of higher rainfall followed by dryer periods roughly every 1000 years • 1950’s to early 1970’s saw above average rainfall • This was followed by drought for the Photograph copyright Ewan Robinson last 30 years
  11. 11. Topic 3.4: Soil System Topic 3.5: Food Resources Grazing and Soil degradation The Story of the Sahel: population effects Photograph copyright Ewan Robinson
  12. 12. Topic 3.4: Soil System Topic 3.5: Food Resources Grazing and Soil degradation The Story of the Sahel: population effects • Population in the region is doubling every 20 years Photograph copyright Ewan Robinson
  13. 13. Topic 3.4: Soil System Topic 3.5: Food Resources Grazing and Soil degradation The Story of the Sahel: population effects • Population in the region is doubling every 20 years • Population growth (3%) exceeds growth in food production (2%) Photograph copyright Ewan Robinson
  14. 14. Topic 3.4: Soil System Topic 3.5: Food Resources Grazing and Soil degradation The Story of the Sahel: population effects • Population in the region is doubling every 20 years • Population growth (3%) exceeds growth in food production (2%) • Poverty is widespread - three of the four poorest countries on Photograph copyright Ewan Robinson Earth are in the region
  15. 15. Topic 3.4: Soil System Topic 3.5: Food Resources Grazing and Soil degradation The Story of the Sahel: Grazing and firewood Photograph copyright Ewan Robinson
  16. 16. Topic 3.4: Soil System Topic 3.5: Food Resources Grazing and Soil degradation The Story of the Sahel: Grazing and firewood • Increasing population has led to Photograph copyright Ewan Robinson
  17. 17. Topic 3.4: Soil System Topic 3.5: Food Resources Grazing and Soil degradation The Story of the Sahel: Grazing and firewood • Increasing population has led to • Overgrazing Photograph copyright Ewan Robinson
  18. 18. Topic 3.4: Soil System Topic 3.5: Food Resources Grazing and Soil degradation The Story of the Sahel: Grazing and firewood • Increasing population has led to • Overgrazing • Removal of trees for firewood Photograph copyright Ewan Robinson
  19. 19. Topic 3.4: Soil System Topic 3.5: Food Resources Grazing and Soil degradation The Story of the Sahel: Grazing and firewood • Increasing population has led to • Overgrazing • Removal of trees for firewood • This is combined with poor farming methods Photograph copyright Ewan Robinson
  20. 20. Topic 3.4: Soil System Topic 3.5: Food Resources Grazing and Soil degradation The Story of the Sahel: Grazing and firewood Increasing population More food required More Increased livestock grazing More fuel Deforestation needed for for firewood cooking Removal of vegetation Soil exposed to wind and water Top soil can blow away SOIL EROSION
  21. 21. Topic 3.4: Soil System Topic 3.5: Food Resources Grazing and Soil degradation The Story of the Sahel: Grazing and firewood Increasing population More food required • Leads to: More livestock Increased grazing More fuel Deforestation needed for for firewood cooking Removal of vegetation Soil exposed to wind and water Top soil can blow away SOIL EROSION
  22. 22. Topic 3.4: Soil System Topic 3.5: Food Resources Grazing and Soil degradation The Story of the Sahel: Grazing and firewood Increasing population More food required • Leads to: More livestock Increased grazing • Fewer plants to hold the soil More fuel Deforestation together needed for for firewood cooking Removal of vegetation Soil exposed to wind and water Top soil can blow away SOIL EROSION
  23. 23. Topic 3.4: Soil System Topic 3.5: Food Resources Grazing and Soil degradation The Story of the Sahel: Grazing and firewood Increasing population More food required • Leads to: More livestock Increased grazing • Fewer plants to hold the soil More fuel Deforestation together needed for for firewood cooking • Soil surface exposed to wind Removal of vegetation Soil exposed to wind and water Top soil can blow away SOIL EROSION
  24. 24. Topic 3.4: Soil System Topic 3.5: Food Resources Grazing and Soil degradation The Story of the Sahel: Grazing and firewood Increasing population More food required • Leads to: More livestock Increased grazing • Fewer plants to hold the soil More fuel Deforestation together needed for for firewood cooking • Soil surface exposed to wind Removal of vegetation Soil exposed • Loose top soil blows away to wind and water Top soil can blow away SOIL EROSION
  25. 25. Topic 3.4: Soil System Topic 3.5: Food Resources Grazing and Soil degradation The Story of the Sahel: Grazing and firewood 20 Area Harvested (million ha) 10 1960 1970 1980 1990 2000 2010 Increase in area of land being harvested each year (UNEP)
  26. 26. Topic 3.4: Soil System Topic 3.5: Food Resources Grazing and Soil degradation The Story of the Sahel: Grazing and firewood 20 • Is grazing really the big problem? Area Harvested (million ha) 10 1960 1970 1980 1990 2000 2010 Increase in area of land being harvested each year (UNEP)
  27. 27. Topic 3.4: Soil System Topic 3.5: Food Resources Grazing and Soil degradation The Story of the Sahel: Grazing and firewood 20 Area Harvested (million ha) 10 1960 1970 1980 1990 2000 2010 Increase in area of land being harvested each year (UNEP)
  28. 28. Topic 3.4: Soil System Topic 3.5: Food Resources Grazing and Soil degradation The Story of the Sahel: Grazing and firewood • Increased population has led to a 20 need to expand agriculture for Area Harvested (million ha) both local use and export 10 1960 1970 1980 1990 2000 2010 Increase in area of land being harvested each year (UNEP)
  29. 29. Topic 3.4: Soil System Topic 3.5: Food Resources Grazing and Soil degradation The Story of the Sahel: Grazing and firewood • Increased population has led to a 20 need to expand agriculture for Area Harvested (million ha) both local use and export • Increase the amount of poor 10 quality land used to grow crops 1960 1970 1980 1990 2000 2010 Increase in area of land being harvested each year (UNEP)
  30. 30. Topic 3.4: Soil System Topic 3.5: Food Resources Grazing and Soil degradation The Story of the Sahel: Grazing and firewood • Increased population has led to a 20 need to expand agriculture for Area Harvested (million ha) both local use and export • Increase the amount of poor 10 quality land used to grow crops • Leads to increased soil 1960 1970 1980 1990 2000 2010 degradation in dry years Increase in area of land being harvested each year (UNEP)
  31. 31. Topic 3.4: Soil System Topic 3.5: Food Resources Grazing and Soil degradation The Story of the Sahel: Additional factors Chad Sudan Central African Republic Conflict in the Dafur region disrupts traditional nomadic migration routes
  32. 32. Topic 3.4: Soil System Topic 3.5: Food Resources Grazing and Soil degradation The Story of the Sahel: Additional factors • Traditional agriculture was dependent on nomadic herding Chad Sudan Central African Republic Conflict in the Dafur region disrupts traditional nomadic migration routes
  33. 33. Topic 3.4: Soil System Topic 3.5: Food Resources Grazing and Soil degradation The Story of the Sahel: Additional factors • Traditional agriculture was dependent on nomadic herding • Post colonial borders cut across migration Chad Sudan paths Central African Republic Conflict in the Dafur region disrupts traditional nomadic migration routes
  34. 34. Topic 3.4: Soil System Topic 3.5: Food Resources Grazing and Soil degradation The Story of the Sahel: Additional factors • Traditional agriculture was dependent on nomadic herding • Post colonial borders cut across migration Chad Sudan paths • Civil war and political unrest in the region Central African Republic leads to migration from rural areas to the towns, intensifying grazing around urban areas Conflict in the Dafur region disrupts traditional nomadic migration routes
  35. 35. Topic 3.4: Soil System Topic 3.5: Food Resources Grazing and Soil degradation The Story of the Sahel: The Results
  36. 36. Topic 3.4: Soil System Topic 3.5: Food Resources Grazing and Soil degradation The Story of the Sahel: The Results • Smaller and smaller areas of grazing have to support larger herds
  37. 37. Topic 3.4: Soil System Topic 3.5: Food Resources Grazing and Soil degradation The Story of the Sahel: The Results • Smaller and smaller areas of grazing have to support larger herds • Cattle more susceptible to disease and death
  38. 38. Topic 3.4: Soil System Topic 3.5: Food Resources Grazing and Soil degradation The Story of the Sahel: The Results • Smaller and smaller areas of grazing have to support larger herds • Cattle more susceptible to disease and death • Famine affects the growing population

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