• Students begin Ecosystems by setting up a terrarium in which they grow grass, mustard, and alfalfa plants. Then they add crickets and isopods. They also set up an aquarium into which they introduce snails, guppies, elodea, algae, and duckweed. By connecting the terrarium and aquarium, students are able to observe the relationship between the two environments and the organisms living within them. Using test ecocolumns that contain only plants, students simulate the effects of pollutants—such as road salt, fertilizer, and acid rain—on an environment.

    Students then use a food-chain wheel to make inferences about the effects these pollutants might have on their own miniature ecosystems. Later, students read about, explore, and discuss the Chesapeake Bay as a model ecosystem. They analyze this ecosystem from the viewpoint of various users—waterman, dairy farmer, land developer, recreational boater, and resident—and present their findings to the class. The activity enables students to appreciate the trade-offs that must be made to reach mutually acceptable solutions to environmental problems.