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Eutrophication Lab

For Environmental Science Classes

Purpose: To simulate the effects of different amounts of fertilizers spilled in a Fresh water area with viable life forms over a period of time.

Background: It is important for plants to receive the proper nutrients to survive, such as Nitrogen and Phosphorus. However, excessive amounts of fertilizer can cause Eutrophication to occur. Too many nutrients cause the algae and plants to grow too fast and cause them to die. Then, when the microorganisms decompose the plant and algae material, they deplete all the dissolved Oxygen in the water causing to the death of all life in the water that require dissolved oxygen. Eutrophication commonly occurs in areas where fertilizers, animal waste, and detergents with phosphates spill into bodies of water.

Materials: pond water samples, glass jars, fertilizer, stirring rods, microscopes, microscope slides, cover slips, pipettes/dropper, lens paper, grow light, paper, colored pencils, test strips for Phosphate, Nitrite, Nitrate, and pH,and pens/pencils

Procedures:

Day 1

  1. Obtain a jar with your group number. A control jar will be made by the teacher.
  2. Each group will receive a numbered jar with pond water. Students are responsible to remember the jar number for your group.
  3. Students are to go to the proper station to obtain a pipette/dropper, microscope, microscope slide and cover.
  4. Make a wet mount slide-Place one small drop of pond water on the microscope slide and then place a cover slide over the sample. Rinse and the pipette out each time.
  5. Look for microscopic organisms
  6. Draw each microorganism and count how many of each species
  7. Color each organism by its true color
  8. Identify each with a cell phone/I pad/ or computer
  9. Wash out pipette/dropper, microscope slide and cover and then dry the slide and cover with lens paper each time they are used and return to teacher when you are done
  10. Record all information under Raw Data
  11. Get fertilizer from the teacher (teacher will state amount to measure out) and place that amount into the jar and stir thoroughly with a stirring rod for two minutes. Rinse and dry off the stirring rod each time.
  12. The teacher will assist you with the Chemistry portion. You will be checking the Phosphate, Nitrite, Nitrate, and pH levels.
  13. After you are finished with the jar, place in the plastic bin labeled with your block number
  14. Observe changes over the next two weeks every class.

Each class afterwards for the remainder of the two/three weeks

  1. Check for visible differences in your jars-Write down findings under Observations each class (date, appearance, color, odor, and any other observations).
  2. At the end of the two/three weeks check for microscopic life and chemistry again.
  3. Write Lab report (See Rubric below) and answer the following Analysis and Conclusion Questions in appropriate areas:

Analysis Questions:

  1. What was the variable (independent and dependent) in the experiment?
  2. What changes did you observe? Explain
  3. What caused the growth changes?
  4. Did you observe any other organisms other than algae being affected?
  5. Was your group able to stimulate Eutrophication? Explain
  6. What two cycles are involved in Eutrophication?
  7. What changes took place in the chemistry part of the pond water?

Conclusion: Summarized what occurred during the time frame to the control and the jar with the excess fertilizer. Why did you see differences?

Lab Report Directions/Rubric-Worth a Quiz grade

  • ______(10 points)Title of Lab Report top center of paper and then Group member names directly under the title
  • ______(5 points) Scientific Method steps in the correct order
  • ______(10 points) for Identification of microscopic organisms
  • ______(20 points) Daily Observations with dates
  • ______(20 points) Raw data (Chemistry part)
  • ______(20 points) Results (Makea chart with a title of the Raw Data)
  • ______(10 points) Analysis Questions (Written questions and then the answers)
  • ______(5points) Conclusion

This Lab was modified by Mrs. Epperley from online materials from Holt Environmental Science Teacher Resource pages