Causes of soil erosion

Table sort task

Causes of degredationOvergrazing and

agricultural mis- management affect more than 12 million km2 world wide

Worse in Africa and Asia where 20% of worlds pasture has been damaged.

Effects of loss of soil• Increased surface runoff and flooding• Reduced infiltration so groundwater is not replenished - Springs and

wells dry up• Desertification: ‘becoming desert’ - dry land becomes increasingly

arid, losing water/vegetation/wildlife• Development of erosion gullies• Change in surface microclimate – alters albedo and increased dryness• Reduced germination of plants

in most vulnerable areas - FAMINE

Effects of soil erosion……

Desertification: Dust Storms: Topsoil Erosion: Reduced Crop Yields: Conflict:Famine: Increased Use of Chemicals:

Malnutrition – people don’t have enough to eat

refugees – people move to new areas

Famine – people starve

Reduced agricultural output – fewer crops can be grown

Overcultivation, overgrazing and deforestation

Research & Present Soil Degradation Management (Choose Below).Egypt, Turkey, Ethiopia, Chile, China, Nicaragua• Using research, the textbook and your partner, plan a 5 minute presentation

on soil degradation to be presented Wed (2nd half class).

• You will choose one country and illustrate the model:TYPES-CAUSES-EFFECTS-MANAGEMENT STRATEGIES

• You can use only a Powerpoint to explain yourself. You will work in class.

• Same rubric as last time; this time – think about flow, timing and how to speak well using your body, eye contact, gestures and enthusiasm.