7.5 Reducing desertification in hot deserts

Question 1

What is irrigation?

Answer 1

➢ Water from underground sources or from rivers and canals can be sprayed onto crops or used to flood fields

Question 2

Salinization is caused by too much irrigation - what is the problem of salinization?

Answer 2

➢ High rate of evaporation due to too much irrigation can cause a build up of salts on the surface
➢ This means soil fertility is reduced - and can cause plants to die

Question 3

How can tree planting reduce erosion?

Answer 3

➢ The tree roots bind the soil together and the leaves and branches provide shade - grazing for animals and fuelwood

Question 4

How can Magic stones in West Africa reduce soil erosion?

Answer 4

➢ The stones are used as low stone walls

➢ When rain washes down the hillside the walls trap water and soil