Environmental History of the Southwest
Study Guide for Exam #3 (our Final Exam)Modern Issues
NOTE: The exam will be made up of multiple-choice, true-false, fill-in, and short-answer questions.
Anglo Settlement of the SW
- When did the United States make the Gadsden Purchase? When did the railroad connect through the SW?
- Describe impacts of livestock grazing on ecosystems of the Southwest.
- Define arroyos. How do they form? Where do they typically occur?
- Describe impacts of arroyos on the environment.
- Explain arguments for and against the notion that early Anglo livestock overgrazing contributed to the late 1800s episode of arroyo cutting in the Southwest.
- Explain arguments for and against the notion that climatic variation contributed to the late 1800s episode of arroyo cutting in the Southwest.
- Name modern strategies for improved range (livestock) management.
- Discuss the types of evidence used to identify changes in natural fire regimes. How are fire-scarred trees evidence of a surface fire regime?
- What is a "fire history graph" and how can it be used to understand fire history?
- What trends are evident in total area burned per year in the Southwest since the late 1900s? What factors have contributed to this trend?
- Distinguish typical fire frequency and intensity in southwestern ponderosa pine forests before and after the late 1800s-early 1900s.
- What is the prominent natural ignition source of fire in the Southwest? Has natural ignition of fire always been a possibility in the Southwest?
- How did early historic grazing affect fire regimes?
- Contrast surface fires and crown fires. What is the difference between the fuels that create a surface fire and those that create the conditions for crown fire?
- What is forest fuel loading and what is its role in fire regimes?
- Discuss forest fire management strategies to return wildfire to a more natural role in forests. Give pros and cons.
- Wildfire disturbance: Good, bad, or unavoidable phenomenon of environmental life? How can modern society live safely with fire, avoiding its bad aspects while capitalizing on its good side?
- What does "forest health" mean?
- Are defoliating insects a natural part of forest ecosystems? If so, what about them is different today from the past?
- Describe the role of spruce budworm in SW forest fuel loading.
- Describe the role of dendrochronology in studying past insect outbreaks.
- How do different species of trees serve as a "control group" in the study of insect outbreaks in the tree-ring record? How can outbreaks be distinguished from background climatic variation?
- Know the concept of treatment versus control in research.
- Contrast spruce budworm outbreaks of the 20th Century versus those prior to 1900.
- Is there any association between large recruitments of new trees and climate? How does fire fit in?
- Describe multiple lines of evidence of changes in fire occurrence, changes in tree recruitment, and repeat photography of Southwest ponderosa pine forests.
- Forest insect disturbance: Good, bad, or unavoidable phenomenon of environmental life? How can modern society live safely with defoliators, avoiding their bad aspects while capitalizing on their good side?
- Describe Southwestern washes with respect to entrenchment and migrating banks.
- Define river discharge.
- Define drainage basin. What's another term for drainage basin?
- Be familiar with reading a flood hydrograph. Discuss environmental and human factors that influence how flashy or sluggish flooding might be.
- Describe the pluses and minuses of bank reinforcement as a strategy to reduce flooding impacts.
- What causes Southwestern floods to differ from one another (e.g., seasonal timing, style of storm, etc.)?
- Describe recent changes in the occurrence of floods in the Santa Cruz River; don't forget skew.
- Distinguish between the mean and median of a distribution. Which of these values is immune to effects of outlying values?
- How does dendrochronology apply to studying past flooding?
- Flooding disturbance: Good, bad, or unavoidable phenomenon of environmental life? How can modern society live safely with flooding, avoiding its bad aspects while capitalizing on its good side?
- Define drought.
- Describe relative importance of precipitation and temperature in deriving drought indices.
- Describe drought in terms of duration, magnitude, and spatial extent.
- What climatological conditions lead to drought generally?
- Identify different types of droughts depending on the affected system.
- Put the 1950s SW drought in perspective spatially and temporally.
- Put the current SW drought in perspective spatially and temporally.
- How are droughts of the past known?
- Be able to name droughts in SW history (last 1000 years) that impacted human systems somehow; describe their impacts.
- What modern ocean phenomenon seems to associate with occurrence (or not) of multi-year drought in the American Southwest?
- Know basics of the carbon cycle, i.e., relative magnitudes of pools and fluxes.
- Compare today's atmospheric CO2 concentration with that of the pre-industrial past.
- Explain and compare two main human contributions to CO2 flux into the atmosphere.
- Describe the atmospheric greenhouse effect.
- Describe the relationship between atmospheric CO2 and global temperature.
- Put the warming of the instrumental record in context of the last 1000 years.
- How might vegetation of the Southwest migrate with the climate change projected for the future? Desert and/or mountain ecosystems? How is this possible change known?
- What does "ecosystem goods and services" mean? What are some examples?
- How do you personally affect the grand carbon equation of life (i.e., which direction)?
Water: Groundwater, Colorado River, and CAP
- Describe the hydrologic cycle; don't worry about absolute values, just relative sizes of "pools" and fluxes.
- What is significant about the 100th Meridian?
- What is an aquifer?
- List inflows and outflows for Tucson's groundwater budget.
- What are some consequences of overdraft of groundwater?
- What is ground subsidence? Why is subsidence a problem? Is subsidence the same as arroyo formation?
- Is Tucson in imminent danger of running out of groundwater?
- When, what, and where of the Colorado River Compact?
- How might the Colorado River compact negotiators have used tree-ring data in their decision making, if only those data had existed at that time?
- Describe the Central Arizona Project (CAP). What might southern Arizonans do with their CAP allotment?
- In terms of the state-wide water budget, how does Arizona use water?
- Evapotranspiration: Good, bad, or unavoidable phenomenon of environmental life?