Introduction: If you are located near a river, stream, estuary, or lake, this activity will help you
determine how abiotic factors affect river biodiversity.

Materials: DO kit, pH kit, phosphate kit, nitrate kits, thermometer, Secchi disc, ping pong ball,
timer, Krymerer tool, field guides for invertebrates and aquatic plants, bamboo rakes, plastic grid,
water collecting bags, fecal coliform media. Note: Not all materials are needed.

Procedure:
Chemical data that may be collected: Dissolved oxygen content, pH levels, phosphate levels, and
nitrate levels.  Kits by Hach or Lemott are easy to follow and may be used on site if desired.

Physical data that may be collected: Temperature, water clarity using a homemade Secchi disc, current
speed using a ping pong ball and timer over a measured distance, and water depth using a Krymerer tool.
 

Biological data that may be collected: Submerged aquatic vegetation, macroinvertebrates, and fecal coliform counts. For submerged aquatic vegetation, you will need some type of rake. Bamboo rakes are the best because they are flexible, but nets also work. You need to look for plants in water that is typically 3-6 feet deep. Typically, a river may have an indicator species that is sensitive to changes inwater chemistry. You may also find non-native speciesaffecting the health of the river.  Your local county should have keys to help you identify aquatic plants. Try calculating the population density of the submerged aquatic vegetation. Macroinvertebrates can usually be found under rocks. Samples may be collected and identified on site using a homemade plastic grid to calculate the relative numbers. Fecal coliforms counts require removing water samples and running most probable number tests.

Once you have collected and analyzed your data, get political! Have students propose and research the feasibility of solutions to inhibitors of biodiversity affecting your area. Students may propose writing a letter to a local politician or newspaper informing the public of the problem, especially those that live in the watershed area, or they may choose to label sewer drains as “drains to the river” to encourage the use of bio-friendly products for washing the car, and alternatives to fertilizers.

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