Question 1

Discuss the various causes of desertification and then evaluate how extensive the problem is and what has been done to alleviate it.

Accepted Answer

Desertification is the process by which fertile land becomes desert, typically as a result of drought, deforestation, or inappropriate agriculture. There are several causes of desertification, including:

1. Overgrazing: When livestock graze on vegetation excessively, it can lead to soil erosion and loss of plant cover, making the land more susceptible to desertification.

2. Deforestation: Clearing forests for agriculture, logging, or fuelwood can lead to soil erosion and loss of biodiversity, ultimately contributing to desertification.

3. Climate change: Changes in temperature and precipitation patterns can lead to increased aridity and drought, which can exacerbate desertification.

4. Unsustainable agricultural practices: Intensive farming, excessive irrigation, and the use of chemical fertilizers and pesticides can degrade soil quality and contribute to desertification.

5. Urbanization: The expansion of cities and infrastructure can lead to soil sealing, which prevents water infiltration and contributes to desertification.

The problem of desertification is extensive, affecting over 250 million people worldwide and threatening the livelihoods of millions more. It is estimated that around 12 million hectares of productive land are lost to desertification each year.

Efforts to alleviate desertification have included the implementation of sustainable land management practices, such as agroforestry, soil conservation, and water harvesting techniques. International agreements, such as the United Nations Convention to Combat Desertification (UNCCD), have also been established to promote cooperation and action to address desertification at a global level.

Additionally, reforestation and afforestation programs have been implemented to restore degraded land and combat desertification. These efforts aim to improve soil fertility, increase vegetation cover, and mitigate the impacts of desertification.

Despite these efforts, desertification remains a significant environmental and socio-economic challenge, particularly in arid and semi-arid regions. Continued investment in sustainable land management practices, as well as increased awareness and education about the causes and consequences of desertification, are essential to effectively alleviate this pressing issue.

Question 2

The Grand Erg Oriental is an example of a

Accepted Answer

A) gibber plain. 
B) reg desert. 
C) sand sea. 
D) sand desert in China. 
E) desert pavement 
A) gibber plain. 
B) reg desert. 
C) sand sea. 
D) sand desert in China. 
E) desert pavement C

Question 3

Relatively small dunes that are crescentic in shape are termed ________ dunes.

Accepted Answer

A) barchan 
B) star 
C) longitudinal 
D) seif 
E) dome 
A) barchan 
B) star 
C) longitudinal 
D) seif 
E) dome A

Question 4

A 50 km · h⁻¹ wind blowing for 24 hours moves how much sand over 1m²

Accepted Answer

A) 10 kg 
B) 50 kg 
C) 500 kg 
D) 1000 kg 
E) 2000 kg 
A) 10 kg 
B) 50 kg 
C) 500 kg 
D) 1000 kg 
E) 2000 kg

Question 5

A crescent-shaped dune with anchoring vegetation is called a

Accepted Answer

A) barchanoid ridge. 
B) longitudinal dune. 
C) parabolic dune. 
D) reversing dune. 
E) dome dune 
A) barchanoid ridge. 
B) longitudinal dune. 
C) parabolic dune. 
D) reversing dune. 
E) dome dune

Question 6

Significant loess deposits are found in the

Accepted Answer

A) Mississippi delta. 
B) Cascade Mountains,Washington state. 
C) Ukraine in the former Soviet Union. 
D) Great Lakes lowlands. 
E) north of the Arctic Circle. 
A) Mississippi delta. 
B) Cascade Mountains,Washington state. 
C) Ukraine in the former Soviet Union. 
D) Great Lakes lowlands. 
E) north of the Arctic Circle.

Question 7

Which of the following is true?

Accepted Answer

A) Playas are located in horsts. 
B) Bajadas are located in horts. 
C) Bolsons run from graben to graben 
D) Horsts are found in bolsons. 
E) Alluvial fans can coalesce to form bajadas. 
A) Playas are located in horsts. 
B) Bajadas are located in horts. 
C) Bolsons run from graben to graben 
D) Horsts are found in bolsons. 
E) Alluvial fans can coalesce to form bajadas.

Question 8

The major erosional processes in the desert are eolian.

Accepted Answer

A) True 
 B)False

Question 9

The smallest features shaped by individual saltating grains are

Accepted Answer

A) ripples. 
B) dunes. 
C) sand seas. 
D) reg deserts. 
A) ripples. 
B) dunes. 
C) sand seas. 
D) reg deserts.

Question 10

Which is true of water use on the Colorado River?

Accepted Answer

A) California has never fully used its share of water. 
B) less water is absorbed by the rocks and evaporates the surface of reservoirs than is alloted to Mexico. 
C) the Colorado River still flows to the ocean. 
D) there are currently eight major dams on the river. 
E) the amount ideally allocated to the United States and Mexico is equal to the average flow. 
A) California has never fully used its share of water. 
B) less water is absorbed by the rocks and evaporates the surface of reservoirs than is alloted to Mexico. 
C) the Colorado River still flows to the ocean. 
D) there are currently eight major dams on the river. 
E) the amount ideally allocated to the United States and Mexico is equal to the average flow.

Question 11

Which of the following is true of eolian ripples?

Accepted Answer

A) they are generally positioned parallel with the direction of the effective wind. 
B) their spacing is controlled by the moisture content of the sand. 
C) they are oriented transversely,or at right angles,to the direction of the wind. 
D) they form reg deserts made up of lag gravels. 
E) exact wind speed can be calculated from their spacing. 
A) they are generally positioned parallel with the direction of the effective wind. 
B) their spacing is controlled by the moisture content of the sand. 
C) they are oriented transversely,or at right angles,to the direction of the wind. 
D) they form reg deserts made up of lag gravels. 
E) exact wind speed can be calculated from their spacing.

Question 12

Which of the following grain sizes is most readily moved by the wind?

Accepted Answer

A) large 
B) intermediate 
C) small 
A) large 
B) intermediate 
C) small

Question 13

What size material comprises the dust in a dust storm that extends thousands of feet above the ground?

Accepted Answer

A) sand 
B) silt and clay 
C) gravel 
D) sand and gravel 
E) sand and clay 
A) sand 
B) silt and clay 
C) gravel 
D) sand and gravel 
E) sand and clay

Question 14

Which of the following is true of alluvial fans?

Accepted Answer

A) they are poor sources of groundwater. 
B) they frequently occur in eastern North America. 
C) the largest sized sediment is found near the top of the fan,and the smallest near the bottom. 
D) they are erosional features. 
E) they develop because of the continuous flow of stream water over their surface. 
A) they are poor sources of groundwater. 
B) they frequently occur in eastern North America. 
C) the largest sized sediment is found near the top of the fan,and the smallest near the bottom. 
D) they are erosional features. 
E) they develop because of the continuous flow of stream water over their surface.

Question 15

Dry,arid climates occupy approximately what percentage of Earth's land surface?

Accepted Answer

A) 5 percent 
B) 10 percent 
C) 26 percent,and as much as 35 percent if all semiarid climates are considered 
D) 65 percent 
E) 84 percent 
A) 5 percent 
B) 10 percent 
C) 26 percent,and as much as 35 percent if all semiarid climates are considered 
D) 65 percent 
E) 84 percent

Question 16

Which of the following is true?

Accepted Answer

A) Playas are located in bolsons. 
B) Bolsons are located in playas. 
C) Bolsons and playas are geographically separate landforms that bear no topographic relationship to one another. 
A) Playas are located in bolsons. 
B) Bolsons are located in playas. 
C) Bolsons and playas are geographically separate landforms that bear no topographic relationship to one another.

Question 17

The spatial distribution of Earth's dry regions are attributable to

Accepted Answer

A) subtropical high-pressure cells between 15° and 35° N and S latitudes. 
B) rain shadows windward of mountain ranges. 
C) the equatorial low-pressure region and the ITCZ. 
D) proximity to moisture-bearing air masses. 
A) subtropical high-pressure cells between 15° and 35° N and S latitudes. 
B) rain shadows windward of mountain ranges. 
C) the equatorial low-pressure region and the ITCZ. 
D) proximity to moisture-bearing air masses.

Question 18

The lowering of the land surface by the lifting and removal of material is termed ________,whereas the grinding of rock surfaces with a "sandblasting" action is ________.

Accepted Answer

A) abrasion deflation 
B) deflation abrasion 
C) saltation abrasion 
D) mass wasting deflation 
E) aggradation diminution 
A) abrasion deflation 
B) deflation abrasion 
C) saltation abrasion 
D) mass wasting deflation 
E) aggradation diminution

Question 19

The Basin and Range Province was formed by

Accepted Answer

A) earthquakes. 
B) tensional forces resulting from the fact that North America overrode a subducted ocean plate and was raised and stretched in the process. 
C) compressional forces resulting from the collision of North America with a microplate,and which resulted in the creation of a folded mountain belt. 
D) landslides. 
E) volcanic activity. 
A) earthquakes. 
B) tensional forces resulting from the fact that North America overrode a subducted ocean plate and was raised and stretched in the process. 
C) compressional forces resulting from the collision of North America with a microplate,and which resulted in the creation of a folded mountain belt. 
D) landslides. 
E) volcanic activity.

Question 20

The skipping and bouncing action of saltation accounts for

Accepted Answer

A) hydraulic lifting by air movements. 
B) the transport of very small grains,smaller than 0.01 mm in diameter. 
C) about 80 percent of wind transported particles. 
D) little or no surface creep. 
E) is directly related to the suspension of particles in the air. 
A) hydraulic lifting by air movements. 
B) the transport of very small grains,smaller than 0.01 mm in diameter. 
C) about 80 percent of wind transported particles. 
D) little or no surface creep. 
E) is directly related to the suspension of particles in the air.

Exam 15: Eolian Processes and Arid Landscapes

Discuss the various causes of desertification and then evaluate how extensive the problem is and what has been done to alleviate it.

The Grand Erg Oriental is an example of a

Relatively small dunes that are crescentic in shape are termed ________ dunes.

A 50 km · h⁻¹ wind blowing for 24 hours moves how much sand over 1m²

A crescent-shaped dune with anchoring vegetation is called a

Significant loess deposits are found in the

Which of the following is true?

The major erosional processes in the desert are eolian.

The smallest features shaped by individual saltating grains are

Which is true of water use on the Colorado River?

Which of the following is true of eolian ripples?

Which of the following grain sizes is most readily moved by the wind?

What size material comprises the dust in a dust storm that extends thousands of feet above the ground?

Which of the following is true of alluvial fans?

Dry,arid climates occupy approximately what percentage of Earth's land surface?

Which of the following is true?

The spatial distribution of Earth's dry regions are attributable to

The lowering of the land surface by the lifting and removal of material is termed ________,whereas the grinding of rock surfaces with a "sandblasting" action is ________.

The Basin and Range Province was formed by

The skipping and bouncing action of saltation accounts for

Essentials of Geography

Solar Energy to Earth and the Seasons

Earth's Modern Atmosphere

Atmosphere and Surface Energy Balances

Global Temperatures

Atmospheric and Oceanic Circulations

Water and Atmospheric Moisture

Weather

Water Resources

Climate Systems and Climate Change

The Dynamic Planet

Tectonics, Earthquakes, and Volcanism

Weathering, Karst Landscapes, and Mass Movement

River Systems and Landforms

The Oceans, Coastal Processes, and Landforms

Glacial and Periglacial Processes and Landforms

The Geography of Soils

Ecosystem Essentials

Terrestrial Biomes

Earth and the Human Denominator

Filters

The lowering of the land surface by the lifting and removal of material is termed ,whereas the grinding of rock surfaces with a "sandblasting" action is .