Desertification in the Sahel

Views:
 
Category: Entertainment
     
 

Presentation Description

No description available.

Comments

Presentation Transcript

PowerPoint Presentation:

Desertification in the Sahel

What is desertification?:

What is desertification? Desertification occurs where land is turned into desert. It occurs mainly in semi-arid lands which border the world ’ s major deserts.

What is The Sahel like?:

What is The Sahel like? Semi-arid area. Periods of rainfall and drought. Supports small bushes. Wind-battered trees.

Sahelian Africa:

Sahelian Africa Sahel: A semiarid region of north-central Africa south of the Sahara Desert

Physical impacts of desertification:

Physical impacts of desertification Soil erosion. Sun baked, cracked soil. Loss of plants and animals. Dry rivers. Growth of desert. Increase in sand storms. Flash floods.

Human impacts of desertification:

Human impacts of desertification Crops and cattle die, resulting in famine. Death. Migrants move to cities, resulting in the growth of informal settlements, shanties, in already massively overpopulated urban areas.

Human reasons for land degradation:

Human reasons for land degradation Traditional nomadic tribes settle in one place. Vegetation no longer protects the soil. Trees provided protection for the soil, from wind and rain. The growing of cash crops, depletes the soil fertility of the area. The soil structure breaks down. Overgrazing. Cutting down trees. Intensive agriculture. ‘Desertification’ - caused by climate change. ‘Land degradation’ - caused by human activity

PowerPoint Presentation:

The Sahel regions are areas which experience desertification.

PowerPoint Presentation:

Why does the Sahel suffer from desertification? DESERTIFICATION Increase in population Increase in cattle Deforestation for fire wood Grassland grazed more intensively Roots no longer hold soil together Roots may be eaten as well as grass Leaves no longer protect soil from weather Less vegetation means less protection from weather Loose top soil blown away by wind (Soil Erosion) = Loose top soil blown away by wind (Soil Erosion) = DESERTIFICATION

INTRODUCTION :

INTRODUCTION Tens of millions of people across more than half the states in sub-Saharan Africa need urgent food aid, but the causes are often complex and varied. Food crises were once primarily triggered by natural disasters like droughts. But according to research by the UN Food and Agriculture Organization, man-made causes are increasingly to blame. These include conflict and poor governance, as well as HIV/Aids. Rural poverty, international trade barriers, overpopulation, deforestation, poor use of land and environmental problems can also be factors.

ETHIOPIA:

ETHIOPIA Estimated population: 77.43m Projected number needing food aid: 1.7m Key underlying reasons: Drought Refugees High food prices Overpopulation Estimated population: 13.95m Projected number needing food aid: 3m Key underlying reasons: After-effects of 2004 drought and locusts NIGER

DEMOCRATIC REP. OF CONGO :

DEMOCRATIC REP. OF CONGO Estimated population: 57.54m Projected number needing food aid: 3m Key underlying reasons: Conflict Refugees War, malnutrition and disease have killed at least 3.8m people in the Democratic Republic of Congo in the last seven years. Estimated population: 36.23m Projected number needing food aid: 6.1m Key underlying reasons: Conflict in western Darfur region has displaced 2m people South recovering from long-running civil war Drought in parts Where farming is taking place, it is on a very small scale with most people cultivating with a simple hand tool called a 'maloda'. SUDAN

Is the Sahel too densely populated?:

Is the Sahel too densely populated? Population density, measured by number of inhabitants per sq km, is low in the Sahel. The Gambia has 85 people per sq km (by comparison, Germany has 223 people per sq km). Senegal has 38, Burkina Faso 34, and the remaining four have an average of less than seven people per sq km. However, only a small portion of the total land area of the Sahel is suitable for ecologically and economically sound agriculture. The ratio of inhabitants to available agricultural land thus presents a much darker picture than the low population density might suggest. The highest population densities relative to cultivable land are 633 people per sq km in Mauritania, 293 in Mali, and 228 in Burkina Faso. In Senegal the rate is lowest at less than 100 people per sq km

Tackling desertification:

Tackling desertification Plant Trees. Roots bind the soil together. Leaves provide shade, and intercept water. Cheap, long term. Provide fuel wood and building materials.

Tackling desertification:

Tackling desertification Terracing. Prevent rainfall from washing away topsoil and nutrients. Cheap to build, only man power needed.

Tackling desertification:

Tackling desertification Magic Stones. Similar to terracing, stones are placed along contours. Topsoil can not be washed past the stones. Water infiltrates, instead of running over the surface. Cheap to build, only man power needed. Effective, shown to increase yields by 50%.

Desertification: click here for animation:

Desertification: click here for animation

authorStream Live Help