[biofilms & biodiversity]

Let's Calculate Biodiversity
You're The Expert

It is your turn to determine the biodiversity of an area that interests you. In this exercise, you will be applying what you have learned about species richness and other measures of biodiversity in the previous exercises.
  1. The first step is to choose an area of study.

    For example, you might examine the biodiversity of:

    • Biofilm-forming organisms living in a nearby creek, stream, river or bay
      (learn how to make your own biofilm rack).
    • The plant species on the school grounds or at a botanical garden.
    • Microorganisms found in water, soil or air samples.
    • Something about the students in your class. you could study hair color, types of pets (none, breed of dog or cat, fish, birds) or types of pens and pencils (brand, how they work).
    • Your own research project (use your imagination).

  2. Identify and count the number of different items.

    Remember, the underlying assumptions are:

    1. The categories are well known.
    2. All categories are equally different.
    3. Use a measure of species importance.
    4. The community under study is well defined.
    A complete explanation may be found in our discussion about biodiversity.

  3. To begin analyzing your data, please answer the following questions:

    1. Please give a descriptive title for your study.

      (While this is optional, it is a very good idea to use a title. If the data came from a biofilm study discussed in this unit, the entry could be something like Inner Harbor Biofilm Study - August 25, 1997.)
    2. Please give the names of your research group.

      (While this is optional, it is a very good idea to list everyone so they get credit for their work. Using the above example, the entry could be something like Mrs. Smith's 10th grade class.)
    3. How many categories?
    4. What biodiversity measure(s) would you like to have computed?
      Species Richness (S)
      Simpson's Index (D)
      Index Of Similarity (1 - D)
      Reciprocal Index (1/D)
      Shannon-Wiener Index (H)
      Evenness (E)