1. A certain fictional country called Industria is tracking its population data. In 1855, the first year vital statistics were reported for the country, the population was 1.6 million, with a crude birth rate of 43 per 1,000. At that time the population of Industria was growing quite slowly, because of the high death rate of 41 per 1,000. In 1875 the population began to grow very rapidly as the birth rate remained at its 1855 level, while the crude death rate dropped dramatically to 20 per 1,000. Population growth continued to increase in the small country into the late 1800’s, even though birth rates began to decline slowly. In 1895 the crude birth rate have dropped to 37, and the death rate to 12 per 1,000. In that year (1895) a complete census revealed that the population of Industria had grown to 2.5 million. By 1950 population growth gradually began to decline as the death rate remained at its 1895 level, while the birth rate continued to decline to 22 per 1,000. In 1977 vital statistics revealed that the death rate was 10 per 1,000, and that the population growth had slowed even more to an an annual rate of 0.4%. By 1990 Industria had reduced its birth rate to that of its now constant, low death rate, and the population transition was complete. a. Plot the crude birth rate data from 1855 to 1990. On the same graph plot the crude death rate data and clearly label the axes and the curves. b. What was the annual growth rate of Industria in 1950? What was the birth rate in Industria in 1977? c. Indicate TWO factors that might have accounted for the rapid decline in the decline in the death rate in Industria between 1855 and 1895. Indicate one specific reason why the birth rate might have been so high in 1855 and was so slow to decrease between 1855 and 1950. d. Determine what the population size of Industria would have been in 1951 if the population had continued to grow at the annual rate of growth recorded for Industria in 1895. 2.
a. As mentioned in the article, there are several possible explanations for the increase in mountain pine beetles. Provide one reason why fire-suppression policies lead to increased beetle activity. i. Reduced winter mortality of beetle larvae is likely a consequence of global climate change. ii. Describe TWO ways that the activities of the beetles might enhance climate change. b. The widespread death of trees leads to a series of changes in a forest ecosystem. Identify TWO physical changes that occur in the forest ecosystem as the result of the death of mature trees. For each physical change you identify, describe an impact of that change on the forest ecosystem. c. As the article states, the number of managed honeybee colonies has dropped significantly over the past few decades. Describe TWO specific economic consequences of the collapse of the managed honeybee colonies. d. Pollination by native insects is considered an ecosystem service. Identify a different ecosystem service and explain how that service benefits human society.
3. As the world’s population increases and availability of new arable land decreases, providing sufficient food for the world’s human population is becoming increasingly difficult. The table below shows the area of land needed to feed the world’s population from 1900 projected to the year 2060. a. On the graph below, plot the data from the table above and draw a smooth curve.
b. Assume that the maximum arable land area on Earth is 4.00 billion hectares. Using the smooth curve that you created above, determine the year in which the human population is likely to run out of arable land for agriculture. c. Soil quality is a critical factor in agriculture. Identify TWO physical and/or chemical properties of soils and describe the role of each property in determining soil quality. d. Describe TWO viable strategies for reducing the amount of land needed for agriculture. e. One problem that can result from agriculture is soil salinization. (i) Describe how salinization occurs. (ii) Describe one method to prevent or remediate soil salinization. 4. For decades, forest fires in the United States have been suppressed. In 2003 legislation was passed under the Healthy Forests Initiative (HFI) in response to the record-breaking wildfires that had occurred in the early 2000s. Some environmental and conservation groups fear that negative impacts could result if timber companies are encouraged to harvest medium- and large-size trees in federally owned forests while clearing away the smaller trees and underbrush. a. Identify TWO characteristics of forests that develop when fires are suppressed, and explain why the practice of fire suppression does not reduce, but actually increases, the risk of intense and extensive forest fires. b. The effects of the HFI are expected to extend beyond fire reduction. Excluding fire reduction, describe ONE positive and ONE negative effect likely to result from the implementation of the provisions of the HFI. c. Describe TWO ecosystem services provided for humans by forests. Explain how clear-cutting would affect each ecosystem service you describe. d. Identify a specific type of plant community or biome (other than a forest) that is naturally maintained by fire. Explain how the fire maintains the community or biome. 5. Between 1950 and 2000, global meat production increased from 52 billion kilograms to 240 billion kilograms. During this period, the global human population increased from 2.6 billion to 6.0 billion. a. Calculate the per capita meat production in 1950 and in 2000 b. Use the values from part (a) to calculate the change in global per capita meat production during this 50 year period as a percentage of the 1950 value. c. Discuss why it is more efficient to produce grain for human consumption than to produce meat for human consumption. In your answer, consider both land use and energy use. d. Describe TWO environmental consequences of the increase in the production of meat for human consumption. e. Identify and explain one potential advantage and one potential disadvantage for human health of a diet that contains very little meat.
The zebra mussel, a mollusk native to Eurasia, was first discovered in the Great Lakes of North America in 1988. Zebra mussels attach to solid substrates and are filter feeders. Adult zebra mussels can survive for several days or even weeks out of water if the temperature and humidity are favorable. An adult female zebra mussel can produce as many as one million eggs per year. The recent range of occurrence of zebra mussels in the United States is indicated by shading in the map above. a. Why are zebra mussels located primarily in areas in the eastern United States rather than in the western United States? b. How are zebra mussels introduced into isolated lakes? Describe one viable method for preventing the spread of zebra mussels into isolated lakes. c. Identify and explain one impact that zebra mussels can have on aquatic ecosystems. d. Identify another invasive species, either terrestrial or aquatic, and describe one negative impact it has had. e. One strategy for controlling an invasive species has been to introduce another nonnative species to control it; this strategy can often have unintended results. Give a specific example of the use of this strategy and discuss a negative impact of introducing a nonnative species to control an invasive species. f. Discuss TWO specific characteristics of invasive species that enable them to thrive in new environments. 7.
The graph above shows the decline in the catch of ground fish (such as cod, haddock, and flounder) from Georges Bank from 1965 to 1995. This decline in the fish harvest resulted in the closure of large portions of the fishery. a. Identify the five-year period during which the greatest rate of decline in the fish harvest took place. For that fiveyear period, calculate the rate of decline in the fish harvest, in metric tons per year. Show clearly how you determined your answer. b. Choose any TWO commercial fishing practices from the list below. For each of your choices, describe the practice and explain the role it plays in the depletion of marine organisms.
i. Bottom trawling Using sonar ii. Long-line fishing Using drift nets/ gill nets/ purse seines c. Identify one international regulation or United States federal law that applies to the harvesting of marine food resources and explain how that regulation or law helps to manage marine species. d. The oceans of the world are often referred to as commons. Give an example of one other such commons, explain how human activities affect the commons, and suggest one practical method for managing that commons. 8.
a. Describe what an El Nino is and clearly indicate where it occurs. b. Describe the connection between the climate change associated with El Nino and the transmission of diseases. Explain whether the article is correct in its reporting of the various disease epidemics that occur in response to an El Nino. c. People in what part of the world would be most likely to be affected by this link between El Nino and disease? d. Clearly describe two other important environmental problems associated with ENSOs.
9. The Alaskan National Wildlife Refuge (ANWR) on Alaska’s North Slope is frequently in the news because petroleum geologists estimate that there are billions of barrels of economically recoverable oil beneath the surface of its frozen tundra. According to a 1998 United States Geological Survey (USGS) estimate, ANWR could contain up to 10 billion barrels of technically recoverable oil. Oil company officials advocate openining the refuge to oil exploration and the subsequent development of its petroleum resources. Environmentalists argue that oil exploration and development will damage thie fragile ecosystem and urge Congrress to protect ANWR by designating it as a wilderness area. a. The Unite States consumes approximately 20 million barrels of oil per day. According to the USGS estimate, for how many days would the technically recoverable oil resource in ANWE supply the total United States demand for oil? b. Describe TWO charateristis of artic tundra that make it fragil and explain how these two charcterists make the tundra particularly suceptible ot damage from human impacts. c. Indentify TWO activities that would be associated with the development of ANWR petroleum resources and describe a substasntial environmental impact of EACH in ANWR. d. Indentify and describe TWO major end uses of the 20 million barrels of oul that the United States consumes each day and for each use describe a conservation measure that would substantially reduce United Staes consumption.
a. Support Dr. Tate’s assertion that “the leaf litter is critical to the survival of local species of forest plants. Include in your discussion the roles of leaf litter in a deciduous forest ecosystem. b. Describe THREE abiotic changes that would be likely to result if the exotic worms consumed all the leaf litter in a single year. c. For one of the changes you identified in part (b), explain how the change could set the stage for the takeover of Japanese silt grass or other exotic species. d. Design a controlled experiment to determine whether the worms, in fact, do change the forest ecosystem. Identify the environmental factor you will measure, and include the specific hypothesis you will test and data you will collect.