2. What does the pattern of soil erosion by water across the United States suggest is the most important factor influencing soil erosion?
Choice 1 Topography.
 Choice 2 Land use.
 Choice 3 Rainfall intensity.
 Choice 4 Wind power.

REVIEW QUESTIONS FOR SOIL EROSION

Instructions: underlined and colored text is linked to an image that will help explain the concept in question. These images are popup windows that should be closed when you are done. To choose an answer, click the mouse on a blue button. A popup message will appear to indicate whether your choice is correct or not. Sometimes a popup message will also take you to another image when you click on OK. To escape these images, you must close the popup window.

 

 

 

 

 

 

 

 

 

 

1. Which of the following conditions would lead to the most soil erosion from a single storm?

Choice 1 Heavy rainfall in an area of low average annual rainfall.
 Choice 2 Steep slopes in a tropical rainforest.
 Choice 3 An agricultural region where soil conservation practices have been implemented.
 Choice 4 An area that has been urbanized for several decades.
Choice 4 All of the above would produce roughly the amount of soil erosion.


 

 

 

 

 

 

 

 

 

 

3. Why are agricultural areas especially susceptible to soil erosion?
Choice 1 Agricultural areas typically occur in regions of high annual rainfall.
 Choice 2 Agricultural areas typically occur in regions of moderately steep slopes.
 Choice 3 Farms are typically located near streams.
 Choice 4 Farming often involves plowing the soil.


 

4. What does the term "sediment yield" refer to?
Choice 1 The amount of soil eroded from hillslopes each year by water.
 Choice 2 The amount of soil eroded from the land each year by wind.
 Choice 3 The amount of soil eroded each year by either wind or water.
 Choice 4 The amount of sediment leaving a drainage basin each year in a stream.
 Choice 4 None of the above is correct.

 

 

 

 

5. Why is sediment yield often less than soil erosion in a given drainage basin?
Choice 1 Because streams often cannot carry all of the soil that is eroded.
 Choice 2 Because sediment yield is totally unrelated to soil erosion.
 Choice 3 Because streams naturally evolve towards a graded condition.
 Choice 4 Because a stream's bed load usually exceeds its suspended load.
 Choice 4 Because most drainage basins occur in areas of high annual rainfall.

 

 

 

6. Why were soil conservation efforts in Coon Creek Valley, Wisconsin not successful in reducing Coon Creek's sediment yield?
Choice 1 Because the soil conservation efforts were ineffective in reducing soil erosion.
Choice 2 Because Coon Creek adjusted to the reduced soil erosion by eroding sediments from the valley bottom.
 Choice 3 Because the soil conservation efforts were not implemented throughout the entire drainage basin.
 Choice 4 Because sediment yield is not related to soil erosion.
 Choice 4 This mystery has never been solved.

 

7. Why might a river's suspended-sediment yield not be a good measure of of the total soil erosion from that river's drainage basin?
Choice 1 Because some suspended sediment might come from other sources (i.e., the valley bottom).
 Choice 2 Because the river might not be able to carry all of the soil that is eroded.
 Choice 3 Because the river might not be graded at the time when the suspended-sediment measurements were made.
 Choice 4 All of the above are possible.