Desertification Flashcards
Desertification
Persistent degradation of dryland ecosystems by human activity and climate change
Causes of desertification
Climate change
-less and more unpredictable rainfall
-higher temps
-reduced water supply
Human activity
-population growth
-deforestation
-land for agriculture (overcultivation)
Areas at risk of desertification
surrounding desers
Impacts of desertification on ecosystems
-tipping points reached more quickly
-changes in migration patterns
-increased competition due to reduced habitats
Impacts of desertification on populations
-reduced soil fertility (increased salinity, degraded soil etc)= lower crop yield
-drought and famine= malnutrition
-forced migration= increased conflict of land use
Impacts of desertification on landscapes
-increased soil salinity= development of salt crusts
-soil erosion and loss of topsoil
-vegetation damaged by sand blasting
Four routes to dealing with desertification
-global orchestration (an increasingly globalised world where ecosystem management is reactive to current issues focusing on education, infrastructure etc.)
-order from strength (environmental problems as the ‘development’ focus is more bottom-up but concentrates on security and economic growth)
-TechnoGarden (technology is shared to allow populations affected by future desertification to be proactive in prevention by using green technologies)
-Adapting mosaic (bottom-up proactive scenario where the emphasis is on empowering the development of local adaptations and learning)
changing extent and distribution of hot deserts over the last 10,000 years
Changes in Earth-Sun geometry
Changes in solar output
Changes in volcanic emissions
Continental drift
Changes in albedo
Human responses to desertification
-HIC=Murray-Darling basin, Australia
Partial root zone irrigation to grow wine grapes in desert, higher tech mitigation
-LIC=Adrar Algeria, tunnels to harvest groundwater, Intermediate-tech mitigation
