Desertification: is the process by which land becomes desert Case study: the Sahel • The Sahel is becoming more like desert with thin, dry, sandy soils • Soil erosion has created bare rock • Vegetation is sparse The UN environment programme took up combating desertification as a major part of its work. In the 1990s it argued that desertification threatened nearly a quarter of the Earth’s land surface. How have each of these factors contributed to desertification? desertification climate humans animals Climate • Drought: low rainfall since 1968. • Soils become dry and there is no water left in wells. • Trees die, grass withers and is replaced by poor desert scrub. • Crops fail and cattle feed on poor pasture. • Less roots to protect the topsoil, less humus; soils become more sandy and dry. • Wind erosion removes the soil, causing dust storms, leaving bare rock. Human activity • Population is high and increasing fast. • To increase food supplies more crops are grown and more cattle kept leading to overcultivation and over-grazing. • Yields decline and cattle are undernourished and die. • Demand increases for water as population grows. • Trees are cut down for fuel supplies. • Less vegetation; more dry, bare soil; more wind erosion. Animals/insects • Locusts destroy the crops. • Overgrazing means all vegetation is eaten. • Animals trample the ground reducing it to dust. • Animals die and can’t breed. What are the effects of desertification? Starvation • Food and water shortages lead to malnutrition, famine, disease and high death rates. Aid Programmes Large numbers of people become dependent on food aid programmes. Migration • From rural to urban areas causing overpopulation in towns. • To refugee camps. Solutions? How can we solve the problems of desertification? Solutions • In the short-term, provide food aid and water supplies to prevent suffering. • Improve water supplies by building large reservoirs and drilling deeper wells. • Conserve water in local small-scale schemes eg ‘magic stones’ in Burkino Faso. • Encourage sustainable farming practices (using locally-made tools, not tractors). • Provide drought-resistant seed such as millet (northern Nigeria). GM crops. • Tree planting schemes to reduce soil erosion (Mauritania). • International action to reduce the causes of global warming. Solving the Problems: the results Nov 1992 Nov 1998 Before and after animals have overgrazed and trampled the savanna. Solving the Problems: the results Before After Which scheme do you think solved these problems? Conservation Projects Eden Foundation Founded 1985 in Sweden • • • • • Niger is one of the driest countries in the world, situated south of the Sahara desert. The people are poor and have neither money nor water to spare. Their solution is to bring trees and bushes that can grow naturally in this dry area and give food, even in times of need. There are 250,000 known plant species in the world, but only 20 of them provide 90% of our food so the Eden Foundation grow underexploited, edible trees and bushes to feed the local people. Since their arrival, Eden has served more than 2500 households in the region. The seeds are free and they show the local people how to grow the seed. They also give health advice. Eden Foundation "Thanks to our Eden trees, we've had food to eat even though the millet failed. For the last three years, we haven't had a single good rain in our village and this year's harvest lasted less than a month. Instead, my family has lived from the Eden fruits on our field which gives us food for the day. We depend on it, for there is nothing else to eat around here." - Musa Abari from Garin Farara Charity Events Band Aid: 20th Anniversary raising money for the victims of famine and starvation. Trying to cancel ‘Third world’ debt. Midge Ure and Sir Bob Goldolf Problems? • Civil wars, as in Ethiopia and Sudan prevent aid reaching stricken areas and cause mass migration to refugee camps. • Population growth continues to outstrip food supplies.