What are the types of soil erosion?

Question 1

When does soil erosion become a problem?

Answer 1

• when it occurs more rapidly than soil formation

Question 2

Explain wind erosion and its problems?

Answer 2

• dry, low clay content soils are likely to be loose with little cohesion
• if it is windy and soil is unprotected then it may blow away
• when soil is deposited after it may cover crops or land in urban areas

Question 3

Explain rain splash erosion?

Answer 3

• soil particles are dispersed in all directions

- over time, can cause downhill movement of large amounts of soil

Question 4

Explain surface run off erosion ?

Answer 4

• caused when infiltration capacity of soil has been exceeded
• occurs when rainfall is heavy or prolonged
• occurs when soil is relatively impermeable

Question 5

Explain slumping and landslides

Answer 5

• soil on slopes becomes very wet
• increased mass and lubrication of water makes downward movement of large amounts of soil more likely
• occurs when deep soil on steep soils becomes less stable following deforestation
• roots that held soil together decompose ( landslides occur )

Question 6

Name an example of an area with seasonal rainfall?

Answer 6

• Sub-Saharan Africa
• wind erosion during the dry season
• rainfall erosion during the wet season

Question 7

How does vegetation reduce the rate of soil erosion?

Answer 7

• acts as a natural windbreak ( reduces wind velocity and therefore the kinetic energy to carry away soil particles )
• vegetation cover and leaf litter reduce the impact of raindrops ( soil particles are less likely to be dislodged )
• soil organic matter helps to bind soil particles together
• plant roots hold soil together
• plants increase infiltration of water into soil ( reduces rate of run off which reduces soil erosion )