Chapter 9 - 'Introduction'

Question 1

State what land and its surface layer of soil is significantly linked with.

Answer 1

Water cycle - Filtering, Storing, Releasing water.

Climate regulation - Absorbing/re-radiating Suns energy, storing carbon.

Question 2

State the percentage of food kilojoules provided from land supplies.

Answer 2

99.7%

Question 3

State the depth of the Earths crust.

Answer 3

Up to 40km

Question 4

State wether soil is regarded as renewable or not.

Briefly describe the length of natural soil formation.

Answer 4

Soil is a renewable resource.

The natural process can take up to 500 years to replace just 25cm of topsoil.

Question 5

State the predicted increase of the worlds demand for food compared to today.

Answer 5

By 2030 it is predicted it will increase by 50%

Question 6

State the loss of soil in agricultural regions compared to the rate of soil formation.

Answer 6

10 - 40 times faster

Question 7

State the different types of land degradation:

Answer 7

Wind and water erosion.
Soil salinity.
Water logging.
Deforestation.
Pest invasions.
Soil/water pollution.
Weed infestation.
Desertification.

Question 8

State the amount of land degraded globally.

How much people does this affect.

Answer 8

1. 9 billion hectares.

1. 5 billion people.

Question 9

Describe the spatial association with a counties economy and scale of soil degradation.

Answer 9

There is a strong spatial association between countries of low economic development and large scale land degradation.

Question 10

Define desertification.

Answer 10

The loss of previously productive land in specific dry land regions of the world. It is the process of land becoming more arid and desert like.

Question 11

State the amount of countries affected by desertification.

Answer 11

169

Question 12

Define a ‘Dryland’ region.

Answer 12

Regions that are climatically zoned as arid, semiarid and dry sub humid.