REVIEW QUESTIONS FOR FINAL EXAM
1. Which of the following conditions would lead to the most soil erosion from a single storm?
a. Heavy rainfall in an area of low average annual rainfall.
b. Steep slopes in a tropical rainforest.
c. An agricultural region where soil
conservation practices are implemented.
d. Steep slopes in an urban area.
e. All of the above would produce roughly
the same amount of erosion.
2. Why do agricultural areas often experience the greatest amount of soil erosion?
a. Because they
typically occur in areas of high rainfall.
b. Because they typically occur in areas of
moderately steep slopes.
c. Because farming typically involves
plowing the soil to plant seeds.
d. Because farmers typically remove trees
from their fields.
e. Because farms are typically located near
streams.
3. What does the term "sediment yield" refer to?
a. The amount of
sediment eroded from hill slopes by water.
b. The amount of sediment eroded from the
land by wind.
c. The amount of sediment eroded by either
water or wind.
d. The amount of sediment leaving a
drainage basin in a stream.
e. None of the above is true.
4. Why is sediment yield often less than soil erosion in a given drainage basin?
a. Because streams usually
cannot carry all of the sediment that is eroded.
b. Because sediment yield is totally unrelated to
soil erosion.
c. Because streams naturally evolve towards a graded
condition.
d. Because a stream's bed load usually exceeds
its suspended load.
e. Because most drainage basins occur in areas of
high rainfall.
5. Why were soil conservation efforts in Coon Creek
Valley, Wisconsin not
successful in reducing Coon Creek's sediment yield?
a. Because the soil
conservation efforts were ineffective.
b. Because Coon Creek adjusted to the reduced
soil erosion by eroding
sediments from the valley
bottom.
c. Because the soil conservation efforts were not
implemented throughout
the entire drainage
basin.
d. This mystery has never been solved.
e. Because sediment yield is not related to soil
erosion.
6. Why might a river's suspended-sediment yield not be
a good measure of the
total soil erosion in that river's drainage
basin?
a. Because some suspended
sediment might come from other sources.
b. Because the river might not be able to carry
all of the soil that is eroded.
c. Because the river might not be graded
at the time when the suspended-
sediment yield
measurements are made.
d. All of the above are possible.
e. None of the above.
7. What is a drainage basin?
8. What characteristics of a drainage
basin affect its response to rainfall? In
particular, what characteristics make a drainage basin inefficient?
9. What effect does urbanization have on flood recurrence intervals?
10. What does lag time refer to in the context of flooding?
11. What are the negative consequences to the various flood-control measures?
12. Regulatory floodplains:
a.
are typically defined based on the 100-year flood elevation.
b. are never flooded more than once
in a 100-year period.
c. have a 1% chance of being flooded
in any 100-year period.
d. All of the above are true.
e. None of the above are true.
13. Channelization and flood-control dams:
a.
disrupt a stream's graded condition.
b. require periodic maintenance to be
effective flood-control measures.
c. have been widely used to control
flooding along the Mississippi River.
d. All of the above are true.
e. None of the above are true.
14. True or false: rivers tend to
naturally meander back and forth across their floodplains.
15. Which of the following slope movements would be most likely to occur
as a result of adding weight to the
"head" of the slope?
a)
A slump.
b) A block glide.
c) Soil creep.
d) A debris avalanche.
e) A mudflow.
16. Under what conditions could the addition of weight to a slope trigger a block glide?
a)
When the slope is composed of unconsolidated material.
b) When there is cohesion present
along the potential slip plane.
c) When the potential slip plane is
oriented away from the valley.
d) When the slope has just
experienced a fire.
e) None of the above.
17. Which of the following slope movements could be triggered by heavy rainfall or snowmelt?
a)
A slump.
b) A block glide.
c) A mudflow.
d) A debris avalanche.
e) All of the above.
18. True or false: removing vegetation (and thus weight) from a slope increases its stability.
19. The Portuguese Bend Landslide:
a)
was, technically speaking, not a true landslide.
b) occurred as a result of
above-average rainfall.
c) was proven to be the result
of road construction.
d) might have occurred
even if Crenshaw Blvd. had not been built.
e) occurred as a result of
below-average rainfall.
20. How does a debris flow differ from soil erosion by water?
a)
They differ primarily by the amount of water involved in the process.
b) Soil is not considered
"debris".
c) Soil erosion is much faster
process than is a debris flow.
d) Debris flows only occur
on ash-covered volcanic slopes.
e) Actually, there is no
difference between these processes.
21. Soil creep:
a)
occurs only on moderate to steep slopes.
b) is important mostly because
of the damage it causes to human structures.
c) creates "tracks"
or "chutes" along hill slopes.
d) is most effective in
desert environments.
e) All of the above are true
statements.
22. Debris flows:
a)
can be triggered by periods snowmelt in the spring.
b) typically have a threshold
relationship with rainfall duration.
c) often occur after forest
fires move through mountainous areas.
d) are more likely to
occur along slopes that have little or no vegetation.
e) All of the above are true
statements.
23. True or false: all sinkholes form suddenly, without warning.
24. Collapse sinkholes:
a) can form naturally as subsurface cavities grow larger through time.
b) can form as a result of
human activities, such as groundwater withdrawal.
c)
can form naturally during periods of below-average rainfall.
d) all of the above are true.
25. What factors could
influence the likelihood of sinkhole collapse occurring in an area underlain by
soluble
bedrock?
a) The depth to a subsurface cavity.
b) The type of material present
at the land surface.
c)
Natural variations in rainfall.
d) Groundwater withdrawal for
human use.
e) All of the above.
26. What aspect of a wave form influences its erosive power?
a) Its wave length.
b) Its wave height.
c)
Its wave base.
d) All of the above.
e) None of the above.
27. Why do tsunamis grow so large as they approach the shoreline?
28. True or false: wave refraction causes a concentration of energy in bays.
29. True or false: the distance from a wave crest to its trough is known as the wave base.
30. Which of the following human activities can affect the rate of coastal erosion?
a)
Pumping groundwater from a confined aquifer near the coast.
b) Constructing a dam along a river
that leads to the ocean.
c) Employing soil conservation
practices in a watershed adjacent to the coast.
d) All of the above.
e) None of the above.
31. Why do engineering structures not provide a permanent solution to coastal erosion?
32. At which of the following locations would you expect coastal erosion?
a)
The "upcurrent" side of a groin, jetty or breakwater.
b) An area of shoreline with a
negative sediment budget.
c) At the mouth of a river that
empties into a bay.
d) All of the above.
e) None of the above.