Fecal Coliforms in Antarctica

Part III—“Data Prediction”

by
Stephen C. Nold
Fecal Coliforms in Antarctica
University of Wisconsin-Stout

Sally had spent the day drilling 56 holes through two meters of sea ice to collect her water samples (see her sampling scheme below). Sally needed to quickly return to the station before her samples froze so she could filter the water, place the filters on Petri dishes, and incubate them. Right now, though, she needed help. The snow machine, her only transportation, wouldn’t start in the bitter cold. She was three kilometers out and the temperature was quickly dropping. Luckily, the two-way was working when she called for helicopter support to bring her and her valuable samples to the lab. Two days later, Sally counted the colonies growing on her Petri dishes.

Sample Location Map

Questions

  1. Why did Sally sample the sites you see on the map in the figure?
  2. Using the scheme, fill in the sampling sites with the number of fecal coliforms you think Sally found.
  3. What would you consider to be the “Action Level” of fecal coliform contamination in McMurdo Sound? At what levels would you like to see the National Science Foundation take remedial action?

Go to Part IV—“Decision Time”


Originally published at http://www.sciencecases.org/coliforms/coliforms2.asp

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