Microbiology Lesson

 

Focus Question- How does agricultural runoff effect the bacteria present in water?

 

Background info:

 

There are many types of bacteria present in water, but most of these are nonpathogenic. The ones that we as humans need to concern our selves with are those present in animal waste.  The bacteria that are found in waste are Entercoccus and E.coli.

 

Inquiry Questions-

What are the types of bacteria that are harmful?

What are the sources of these harmful bacteria?

How do you test for these bacteria?

 

Materials:

Water collection bottles

Water samples

Bacteria testing kits- available from Micrology Labs (www.micrologylabs.com). Get the ones in the educational section that test for water quality.

Data from Cold Water Creek and Pond Creek  and GIS map of the area land use

 

Lab Component-

Procedure-

  1. Distribute water samples. (all samples that are collected ahead of time must be chilled)
  2. Follow the instructions in the Micrology Lab Kits.
  3. Collect and compile data.
  4. Graph and map if available

 

Questions

  1. What bacteria were present and how many colonies of each?
  2. Based on data available from health resources on bacterial safe levels, what does your analysis indicate about the safety of the water from which your sample came?
  3. How can these bacteria affect humans?
  4. How can they affect fish populations?
  5. How do you treat or prevent these bacterial problems?
  6. How do the water samples from your area compare to the samples taken from Coldwater and Pond Creeks?
  7. Using the land use map can you draw some conclusions about how land use contributes to bacterial contamination of water?
  8. If there is no agricultural land near your sample water, what are the possible sources of your bacteria?

  

Place students in the role of agents of the EPA .  They are to make recommendations about what to do about the creeks and about the tested water samples. Include health implications from these bacteria.

 

SSS Standards-

 

Enviro                    

D.2.4.5                   

D. 2.4.6

G.2.4.10

G.2.4.6