Droughts and Desertification

why do droughts occur (5)

-not enough water to support vegetation

-low rainfall

-not enough water to sustain ground water and river levels

-ENSO

-change in ocean temperature or wind

environmental impacts of drought (7)

-less water for crops and livestock

-low water table, plants can't get as much water

-increase in salinity

-less evaporation -> less precipitation

-veld fires

-erosion of topsoil -> dust storms -> desertification

-destroyed ecosystems

economical impacts of drought (5)

-poor quality items = lower selling price = less profit

-food shortages = high prices

-malnutrition and poverty increase

-unemployment increase

-farmers struggle

societal impacts of drought (5)

-water shortages lead to conflict

-food insecurity -> mass urban migration

-excess stress on urban areas

-health risks

-water restrictions

impact of drought on developed countries (6)

-more equipped to cope with impacts

-have funding for reservoirs

-have resources for prep and management

-better education

-better infrastructure

-more urban water systems

impact of drought on developing countries (5)

-can't afford to build reservoirs

-no planning, poor management

-high reliance on rainfall for crops (no irrigation systems)

-can't afford awareness or education schemes

-high population = high demand

prevention of drought (7)

-inter-basin transfers

-water storage units for rainfall collection

-boreholes

-early warning systems

-drought resistant crops

-seawater desalination

-fog collection with mesh sheets and catchment

what is desertification?

loss of fertile soil in areas with very low rainfall

contributors to desertification (8)

-farming in fragile areas

-poor agricultural management

-deforestation

-bad soil management

-erosion

-surface mining

-increased population

-no government support

effects of desertification (4)

-food and water shortage -> famine, disease, death

-increased dependence in food aid

-mass migration to cities

-mass migration to other nations' refugee camps

prevention and management of desertification (6)

-hedges/trees around fields = windbreakers to prevent erosion

-terraced slopes to decrease runoff and keep soil moist

-organic filter use

-use braces (not whole trees) for fuel

-allow land to rest after harvesting (crop rotation)

-plant more trees than you destroy

meteorological drought

total rainfall is below average for an extended period

agricultural drought

low rainfall causes fewer crops and a soil water deficiency

hydrological drought

low rainfall causes groundwater to decrease, leading to reduced resevoirs

ecological drought

vegetation suffers from too little rain

socio-economic drought

people and the economy affected by low rainfall