3.A - desertification

Question 1

definition of desertification

Answer 1

• outcome of persistent land degradation - drylands
• causes reduction in agricultural capacity and productivity
• human causes: deforestation, overgrazing and over-cultivation
• physical causes: soil erosion and salinisation

Question 2

those affected

Answer 2

• 2B people affected
• 168 countries affected
• 74% poorest people directly affected
• located: Sahel, Somalia, Ethiopia and Kenya = weak Govs and drought via climate change

Question 3

change in farming practices - shifting cultivation

Answer 3

• sustainable when population and carrying capacity equal
• when pop pressure exceeds carrying capacity increases need for intensive methods
• no fallow periods = no regeneration of soil
• wind erosion and water erosion = farmers forced on ton fragile soils

Question 4

water scarcity

Answer 4

• increased cultivation in drylands via irrigation projects are unsuitable, poorly managed and underfunded
• eg Lake Chad shrunk by 23,000km2 in 30years by an increased demand for irrigated water and damming of lakes feeding into the lake

Question 5

demand for fuelwood

Answer 5

• firewood demand for cooking and lighting
• major cause of deforestation and desertification
• high dependence: Burkina Faso 90%, Chad 89% and Mali 80%
• nutrients ploughed back into the soil via ash (controversial bc of the release of co2)

Question 6

rainfall patterns

Answer 6

• desertification = negative feedback
• drought = land degradation and desertification increase
• precipitation decrease = drought

Question 7

environmental impacts of desertification

Answer 7

• decrease fertility
• no fallow periods = decrease nutrients and food produce
• wind and water erosion = decrease nutrients and yields
• decreased in biodiversity
• decrease in vegetation = change to ecosystems
• increased dust formation, affects cloud form and rainfall patters
• vulnerable to change = fluctuating harvest

Question 8

economic impacts of desertification

Answer 8

• decrease fuelwood = increase purchase of damaging fuel (kerosene) = increasing prices
• food shortages increase food insecurity and dependency on food aid
• decreased income - pastoralism and cultivation of crops

Question 9

social impacts of desertification

Answer 9

• drylands populations increase poverty, are marginalised and remote
• increased migration, desertification refugees (males > females)
• loss of traditional knowledge and skills = decrease in yields

Question 10

political impacts of desertification

Answer 10

• issues with migration cause conflict and disputes

- eg civil wars

Question 11

spiral of decline resulting in desertification produces what kind of feedback?

Answer 11

positive feedback

Question 12

how to mitigate against spiral of decline

Answer 12

• improve sustainability of farming via irrigation methods and water management
• drought resistant crops
• maintaining soil nutrients via fallow fields, set-a-side and break crops
• non-wood energy = solar, biogas and wind power
• mixed farming methods
• loans and grants remove link between agriculture and income as farmers etc can buy tools/ mobile phone to create microcredit scheme
• contraception and education = increase goals/ ambition and diversify jobs