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P.D. Schreuders

crayfish picIntroduction

The crayfish class project combines the biological and engineering sciences to create a self-contained ecosystem. This system must be able to support the lives of 3-4 crayfish by providing the appropriate nutrients. The tank is sealed for periods of one, two, and four weeks during which no modifications may be made to the tank.

A stable living environment for the crayfish is a proper balance between the living and non-living components found within the system. The biological systems that make up the ecosystem include crayfish, plants, water, and bacteria. The interactions between the systems inside the ecosystem must be studied to begin the project (Biota). With this biological knowledge in mind, the students can begin to design and build the ecosystem. The project is a repeating process of data collection, analysis, and tank modification. Students monitor the ecosystem through water testing, data recording, and crayfish observation. Once sufficient data is collected, the students analyze the data to determine what is occurring within the system. Modifications are made based on the data, once the sealing period ends, to correct any problems in the initial ecosystem design . This process is repeated until the students create a self-sustaining ecosystem that keeps the crayfish alive and healthy.

This webpage will offer detailed project information that can be used to conduct a similar experiment, whether developed as a class project or as a personal venture.

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crayfish picInstructions

The goal of this project is to develop a method for creating and sustaining a sealed self contained ecosystem. The class should be split up into 5 groups with one tank of 3-4 crayfish per group. The tank is sealed for periods of one, two, and four weeks. During the sealing periods various tests are run on the tank ecosystem to get information on how the various cycles are being represented within the tank and to see if the ecosystem is stable.

Once a sealing period is over, students are allowed to make modifications to the system based on the results of their tests. By the end of the project, the groups should have developed an ecosystem that can survive and function on its own without being dependant on humans to alter it.

The purpose of this project is to develop a process involved in maintaining a closed self-sustained ecosystem. The students will learn about the maintenance of a sustainable environment and about the requirement of stable environmental conditions for living organisms. Also, the tank ecosystem is modeled as a biosphere. Therefore, by applying the study and analysis of the smaller tank environment, large-scale environmental predictions can be made.

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crayfish picSummary

The goals of this project are ?

  • To design and build a self-contained ecosystem that allows 3-4 crayfish to live and grow healthy.
  • To maintain the appropriate environmental and water quality standards to sustain crayfish life during three sealing periods: one week, two weeks, and four weeks.
  • To compare each ecosystem according to recorded data and crayfish observations so that necessary improvements on the tank design can be made.
  • To improve the tank environmental design after each sealing period so that an optimum ecosystem for the crayfish is achieved.
  • To provide a fun learning experience for the students on ecosystems and biological engineering.
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