First Exam, Spring 1997

Define the following terms (2 points each):
- stand
- biome
- acclimation
- physiognomy
- nitrogen use efficiency
- ecotype
Vegetation management is "site specific." We manage vegetation at a definite spatial scale. Why is this important when deciding on the ecological processes to manipulate/alter in a management plan? Provide one example from class that was used to illustrate this point. (8 points)
We learned (I hope) that grasses with the C4 photosynthetic pathway can produce more biomass in summer here in southeastern Arizona than can those with the C3 photosynthetic pathway. How would you expect the seasonal contribution of C3 vs C4 biomass production on southeastern AZ rangelands to change in the next century, and why? (8 points)
We often observe that several different tree species can occur within a particular forest habitat, but only one or two dominate the mature community. Explain this observation in terms of physiological shade tolerance among forest trees. In your answer provide a graph relating photosynthesis to light intensity. (8 points)
Considering the seemingly overwhelming constraints on vegetation management, why do we bother? Why don't we let nature take care of itself? In other words, what is the overall rationale behind vegetation management? List several specific objectives of vegetation management in your response. (10 points)
Rincon Creek appears to flow less frequently than it did in the past. According to Mark Briggs, what are the primary reasons for the reduction in flow? (4 points)
List three of the four classes of management zones used by the National Park Service. Give an example of at least one of the zones that we observed on the field trip to Saguaro National Park. (5 points)
Answer one of the following. (5 points)
- Describe the general pattern of livestock grazing before and after prescribed fire is used on the King Anvil Ranch.
- Briefly describe the response of mesquite, half-shrubs, and perennial grasses to prescribed fire on the King Anvil Ranch, as explained by Dan Robinett.
Describe the plant with the following seedling description code: 1-0 DF P-45-8-3.5. Would you plant this seedling on a southwestern aspect at 2000 m (6600') in the Santa Catalina Mountains? Why or why not? (6 points)
Graduate:
Think back to the first stop on the field trip to Rincon Creek. Assume that you are responsible for restoring a naturally regenerating riparian gallery forest on this site (just on the floodplain, not in the channel). What kinds of things should you consider? Describe specific steps you would use to create and maintain a gallery forest on the site. (30 points)
Graduate:
Ecosystem health and ecosystem integrity are common phrases in natural resource management. Can we manage for these attributes? If so, how? Incorporate the ideas of at least 2 of the following in your response: (a) Mark Briggs, (b) Holling & Meffe (1996), (c) Dan Robinett, and (d) Mark Pater. (20 points)