Deck 12: Arid Lands, Winds, and Desertification

Question 1

Which of the following is NOT part of the definition of a desert?

A) high temperatures
B) mean annual rainfall of less than 25 centimeters per year
C) capability to evaporate more water than falls as precipitation
D) incapable of supporting abundant life
E) sparse vegetation

Answer 1

high temperatures

Question 2

The five kinds of desert regions include all but which of the following?

A) polar
B) subtropical
C) tropical
D) midlatitude
E) coastal

Answer 2

tropical

Question 3

What type of desert region includes the Sahara Desert of north Africa?

A) polar
B) subtropical
C) rain shadow
D) midlatitude
E) coastal

Answer 3

subtropical

Question 4

Which type of desert region includes the largest dry expanses on Earth?

A) polar
B) subtropical
C) rain shadow
D) midlatitude
E) coastal

Question 5

What is the name given to a desert that lies on the leeward side of a mountain range?

A) over the hill
B) rain shadow
C) intermountain
D) steppe
E) plateau

Question 6

What is thought to be the cause of drought conditions over the past decade in the Southwestern United States?

A) Warmer sea-surface temperatures in the Pacific Ocean
B) Increased rain shadow effect due to uplift of the Sierra Nevada
C) A decrease in the thickness of the ozone layer
D) Deforestation in the Pacific Northwest from logging
E) Dust storms in China causing global dimming

Question 7

What is natural sand blasting by sand grains called?

A) abrasion
B) bump and grind
C) desertification
D) wearing
E) deterioration

Question 8

What is the removal of sediment by blowing it away called?

A) abrasion
B) deflation
C) blow hole
D) sink hole
E) sedimentation

Question 9

What characteristic of a sand dune causes the greatest problems?

A) It is difficult to walk across.
B) It absorbs heat.
C) It migrates.
D) You cannot grow anything on it.
E) It provides poor traction.

Question 10

Which of the following deserts owes its existence to being located far from the ocean in a continental interior?

A) The Gobi
B) Death Valley
C) The Saharan
D) The Atacama
E) The Kalahari

Question 11

What type of desert is associated with upwelling ocean currents?

A) polar
B) subtropical
C) rain shadow
D) midlatitude
E) coastal

Question 12

About what percentage of the Earth's surface is covered by midlatitude deserts and semiarid grasslands?

A) 14%
B) 23%
C) 32%
D) 41%
E) 55%

Question 13

About how much of the Earth's surface is covered by deserts exclusive of semiarid grasslands?

A) 10%
B) 33%
C) 66%
D) 75%
E) 90%

Question 14

Which of the following is NOT one of the ways trees help to stave off desertification?

A) Reduction in the reflectance of solar energy hitting the earth
B) Transpiration of water into the atmosphere
C) Biological weathering by the tree roots
D) Serving as natural windbreaks
E) Pumping deep groundwater with their roots

Question 15

What was the key factor in the natural recovery of desert lands that happened in Kuwait?

A) enforcement of public policies
B) re-planting the area
C) decreased use of groundwater
D) fear of land mines
E) changing rainfall patterns

Question 16

Judge the following sentence according to the criteria given below: The frequency of dust storms impacting Beijing, China, has been increasing BECAUSE fallout of herbicides and pesticides in the Arctic is common.

A) The assertion and the reason are both correct, and the reason is valid.
B) The assertion and the reason are both correct, but the reason is invalid.
C) The assertion is correct, but the reason is incorrect.
D) The assertion is incorrect, but the reason is correct.
E) Both the assertion and the reason are incorrect.

Question 17

Judge the following sentence according to the criteria given below: Desertification results from the expansion of existing deserts BECAUSE dryland ecosystems are extremely vulnerable to inappropriate land use.

A) The assertion and the reason are both correct, and the reason is valid.
B) The assertion and the reason are both correct, but the reason is invalid.
C) The assertion is correct, but the reason is incorrect.
D) The assertion is incorrect, but the reason is correct.
E) Both the assertion and the reason are incorrect.

Question 18

Read carefully through the following sentence and decide which of the options is correct. Analysis of sea surface temperatures in the Indian Ocean indicates that changes in land-use practices in the Sahel of Africa were sufficient to cause desertification.

A) The word "temperatures" should be replaced by "salinities."
B) The word "Indian" should be replaced by "Atlantic."
C) The word "land-use" should be replaced by "farming."
D) The word "sufficient" should be replaced by "insufficient."
E) The word "desertification" should be replaced by "drought."

Question 19

Which of the following is not responsible for the slow recovery of ecosystems from desertification?

A) slight rainfall
B) low species diversity
C) little soil bacterial activity
D) slow plant growth rates
E) frequent flash floods

Question 20

Which of the following is NOT an appropriate measure for reversing desertification?

A) developing drip-irrigation systems
B) keeping grazing stock moving
C) planting drought-tolerant trees
D) establishing wind breaks
E) removing boulders from sand dunes

Question 21

Deserts are not defined on the basis of temperature.

Question 22

The Antarctic and Greenland are true deserts.

Question 23

South America's western deserts are not true deserts because they lie near the ocean.

Question 24

There is a strong concentration of deserts around 30 degrees north and south of the equator.

Question 25

Wind erosion includes both abrasion and deflation.

Question 26

Death Valley is an example of a rain-shadow desert.

Question 27

The rapid growth of large desert cities, such as those in the southwestern U.S., actually helps to reverse desertification by bringing in water from wells and aqueducts.

Question 28

The major causes of desertification are overgrazing and trampling of soil by livestock.

Question 29

Replacement of native vegetation in semiarid regions with cultivated crops helps reverse the effects of desertification.

Question 30

Windblown African dust is a nuisance, but is not a health problem.

Question 31

Desertification is irreversible.

Question 32

China has 20% of the world's population but only 2% of the world's arable land.

Question 33

Sahel is the name given to a certain kind of desert ravine.

Question 34

Oceanic upwelling is caused by density differences in the water mass.

Question 35

Deserts may be classified into categories based on climate belts and an additional category based on human misuse.

Question 36

Increased asthma in Barbados has been correlated with drought-induced dust storms in China.

Question 37

Desertification begins at the edges of a nearby desert.

Question 38

China's "Green Wall"is a belt of large irrigated rice fields that runs parallel to the Great Wall.

Question 39

Natural processes, especially windblown sand, rapidly repair damage to the desert caused by off-highway vehicles.

Question 40

The United Nations recognizes that the causes of desertification are straightforward and can easily be prevented by proper policy.

Question 41

How does the intertropical convergence zone (ITCZ) relate to deserts?

Question 42

What are some ways that sand dunes can be stabilized?

Question 43

What facilitated the natural recovery of desert land in Kuwait?

Question 44

A severe reduction in wetlands in the San Joaquin Valley of California played a significant role in the severity of the 1977 duststorm. What caused the reduction of wetlands?

Question 45

Why has the Sahel been a focus of attention in recent times?

Question 46

Why is South America the recipient of North African dust rather than the other way around?

Question 47

Explain how coastal dune fields need not originate in desert climates.

Question 48

What are some of the potential health hazards from windblown dust, apart from respiratory and eye irritation?

Question 49

What is the best program for reversing desertification?