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Closing Questions

THEME: Comparing two aquatic systems - the similarities and differences

  1. Of all the data that were collected, list those data that show the greatest similarities between the two aquatic systems. List those data that show the greatest differences between the two systems. After reviewing all these data, describe in your own words, why you think these aquatic systems are different?
  2. Can you explain why two different aquatic systems share some similarities?
  3. What is the trophic status (eutrophic, mesotrophic, oligotrophic) of the places you sampled?

CYCLES: Local hydrologic cycle

  1. In which watershed do you live? What is the name of the nearest creek or stream to your home? What is the name of the largest stream or river in your watershed?
  2. What kinds of industrial, agricultural or other human activities occur in your area that might show up in the examination of water from your watershed as it is about to enter Lake Michigan?
  3. When it rains or snows in your area, where does the water eventually go? What kinds of things are carried along in the water? Where does the water you drink come from and where does the wastewater go?
  4. While you were on the vessel did you see any indications of water conditions that may have resulted from influences that entered the water long before you tested it?

CYCLES: Life cycles

  1. Describe the life cycle of the zebra mussel and explain why exotics like this are very difficult to control.
  2. Describe the life cycle of a midge (bloodworm). Explain how the typical bloodworm fits into the food chain.


  1. Using the data collected on the vessel, plot the temperature at each sampling site. Compare the graphs and point out similarities and differences. Try to explain these similarities and differences.
  2. Develop a chart that will allow you to show the types and relative abundance of benthic organisms that were collected from each sampling site.
  3. Develop a chart that will allow you to show the type and relative abundance of planktonic organisms for each of the sampling sites.


  1. Diagram the planktonic food chain for each of the sampling sites. How are they the same and how are they different.
  2. Diagram a benthic food chain for each of the sampling sites. How are they the same and how are they different?
  3. How have exotic species influenced food chains and food webs?

Questions for Students to Research

  1. What are the five Great Lakes? Which has the greatest surface area? Which is the deepest? Which has the least surface area? Which is the shallowest? How deep is Lake Michigan?
  2. How long is the Grand River or the Muskegon River? What percentage of the State of Michigan does the Grand River or the Muskegon River drain? Where does the river start? Where does it end?
  3. What is the name of the watershed where your home is located? Where do you get the water for your house? Where does your wastewater go?
  4. What size freighters come into the harbor? What size are the largest freighters on the Great Lakes? What modifications have been made to the harbor to accommodate the large freighters that enter this port? What do freighters deliver and what do they take out?
  5. What environmental issues arise from the transportation of petroleum by water? What do we obtain from petroleum?
  6. When a power plant burns coal, how is the coal soot prevented from escaping the smokestack? What does escape from the stack? Why is water taken by power plants from the river or lake? When water is returned to the river or lake, what precautions must be taken?
  7. What are the various materials stored at the commercial docks along the water (black, gray, brown, orange, white, in the silos)? Why are some materials stored under a tarp? What are two possible properties of materials covered by the tarp? Which water quality parameter would change with leakage of this material to the lake or river?
  8. Why are sand dunes so important? Why are they such fragile ecosystems? How were sand dunes formed? Why are they so pure (e.g., no gravel)? What do we make with sand? Why do we permit sand dunes to be mined? What advantages are there to sand dune mining? Disadvantages?
  9. How has shoreline development such as marinas, hotels, condominiums, and houses impacted the aquatic ecosystem? What has been done in the area to promote tourism? How have these things impacted the area?
  10. How large is Spring Lake or Muskegon Lake? Describe the bottom sediments from this lake. Why are these sediments like this? What organisms live in these sediments? How are they able to exist at such low oxygen levels?
  11. Describe the bottom sediments from Lake Michigan. What organisms were found in these sediments? How does this differ from Spring Lake or Muskegon Lake?
  12. What is biodiversity? What types of organisms live in the water of Lake Michigan? Spring Lake? Muskegon Lake? a River? What is the biodiversity of Lake Michigan as compared to the other bodies of water sampled?
  13. What kinds of fish will you find in Lake Michigan? Why? What kinds of fish will you find in Spring Lake or Muskegon Lake? Why? How does dissolved oxygen relate to the fish?
  14. What is the turbidity in NTUs for a vial of pure water? If you are given a vial of water from Lake Michigan, one from the Grand River, and one from Spring Lake, which will have the highest turbidity? Why? Which will have the lowest turbidity? Why?
  15. What things will cause conductivity readings to be high? What range of conductivity should we expect in Lake Michigan? a river?
  16. What is the plume line? What causes this line? How do the winds affect its size, shape, and sharpness?
  17. Why are all of the pH readings taken in Lake Michigan above 7.0 (not acidic)? What happens to the acid rain that falls into Lake Michigan? Would the same be true in all of Michigan?
  18. What is a thermocline? How do we find the depth of the thermocline? What causes the fall and spring turnovers of lakes?
  19. What non-native species (both plant and animal) have entered the Great Lakes ecosystem? How did they arrive? From where did they come? What problems do they cause? Why do they cause such problems?
  20. What is the Great Lakes Water Quality Agreement? What are Areas of Concern in the Great Lakes? What are PCBs? What is the Lake Michigan Lakewide Management Plan (LaMP)? What is the Lake Michigan Mass Balance Study?
  21. The following are basic questions frequently asked by the public about the Great Lakes that the U.S. Environmental Protection Agency and Environment Canada have identified in the annual State of the Great Lakes Report:
    • Can we swim, eat the fish that we catch, and drink the water?
    • Are the Lakes affecting human health?
    • Are the Lakes getting better?
    • Are the fish and birds healthy?
    • How are endangered species doing?
    • What are we doing about exotic (non-native) species?