Desertification in the Sahel

Views:
 
Category: Entertainment
     
 

Presentation Description

No description available.

Comments

Presentation Transcript

PowerPoint Presentation:

The lives of approximately 300 million people have been affected by intense soil degradation (desertification) in the Sahel. About 3.6 billion hectares of the worlds land mass has been affected by desertification. Desertification is the process whereby a combination of human and climatic changes change fertile farming land into unproductive desert. Only once in the last 3 decades of the twentieth century was the annual rainfall in the Sahel greater than the long term average. The pattern continues now. High temperatures cause a high rate of evapotranspiration and moisture loss from the soil Rainfall is infrequent an intense. Heavy showers cause soil erosion. Timbuktu in Mali receives 70% of its annual rainfall in 2 months. Overgrazing occurs where animal herds are too large and the cattle graze continually on the same piece of land, eating not only the grass but the roots as well. This means that it is not able to re-grow, and the land is therefore not being sustainably developed. As the population increases, overcultivation (the continual use of the soil leading to loss of fertility) occurs. In some areas of the Sahel, people are encouraged to grow cash crops for sale in the city markets and for export. Growing the same crop year after year without any rest leads to rapidly declining soil fertility. This has happened in Chad where the government has tripled the area of cotton cultivation. A growing population requires more fuel wood. This leads to deforestation, leaving the soil more vulnerable to erosion. In Sahel, 80% of domestic energy comes from firewood. The Sahel takes up 650 000 km sq. Malam Garba now farms an area 2 times as big as 40 years ago, but his harvest of millet is of 1/7 of what is used to be. 40 years ago, Malab Garba and his brother harvested 700 baskets of millet from their fields. The National Department of the Environment said that 250 000 hectares of land are being lost each year due to desertification. The population of Sudan and Ethiopia increased by 300% in the past 50 years, contribution to the desertification of the land. The Eden Foundation is a Swedish Aid organisation in Mali. It researched indiginous species of drought resistant trees and bushes. They practice direct seeding of plants as this makes the roots depper. Farms on the downwind side of the project were getting harvests 3 x as much due to protection from erosion by eden bushes. Local farmers saw the benefit and now 2500 of them use these seeds. Fufther benefit is that all produce frutis which can be sold creating extra funds of $150 per family average

PowerPoint Presentation:

The lives of approximately ________ people have been affected by intense soil degradation (desertification) in the Sahel. About _______ hectares of the worlds land mass has been affected by desertification. ___________ is the process whereby a combination of human and climatic changes change fertile farming land into unproductive desert. High temperatures cause a high rate of evapotranspiration and moisture loss from the soil Rainfall is infrequent an intense. Heavy showers cause soil erosion. Timbuktu in Mali receives __% of its annual rainfall in _ months. Overgrazing occurs where animal herds are too large and the cattle graze continually on the same piece of land, eating not only the grass but the roots as well. This means that it is not able to re-grow, and the land is therefore not being sustainably developed. As the population increases, overcultivation (the continual use of the soil leading to loss of fertility) occurs. In some areas of the Sahel, people are encouraged to grow cash crops for sale in the city markets and for export. Growing the same crop year after year without any rest leads to rapidly declining soil fertility. This has happened in _____ where the government has tripled the area of _____ cultivation. A growing population requires more fuel wood. This leads to deforestation, leaving the soil more vulnerable to erosion. In Sahel, __% of domestic energy comes from firewood. The Sahel takes up 650 000 km sq. Malam Garba now farms an area 2 times as big as 40 years ago, but his harvest of millet is of ___ of what is used to be. 40 years ago, Malab Garba and his brother harvested ___ baskets of millet from their fields. The National Department of the Environment said that _______ hectares of land are being lost each year due to desertification. The population of Sudan and Ethiopia increased by ___% in the past 50 years, contribution to the desertification of the land. The Eden Foundation is a Swedish Aid organisation in Mali. It researched indiginous species of drought resistant trees and bushes. They practice________ of plants as this makes the roots deeper. Farms on the downwind side of the project were getting harvests _______ as much due to protection from erosion by eden bushes. Local farmers saw the benefit and now ______ of them use these seeds. Fufther benefit is that all produce frutis which can be sold creating extra funds of _____ per family average Only once in the last 3 decades of the twentieth century was the annual rainfall in the Sahel greater than the long term average. The pattern continues now.

authorStream Live Help