Matter Routes at Cedar Cove Canoe Camp

A Change at Cedar Cove

Cedar Cove Canoe Camp sits beside a quiet pond. Pondweed grows in the shallow water near the dock. Mallard ducks paddle through the pond and sometimes nibble pondweed. Small organisms such as fungi and bacteria live in the wet mud and on dead material. Camp naturalists observed the cove for ten days without removing plants, ducks, or mud.

At the beginning, the naturalists marked one patch with 30 pondweed leaves. During the next few days, sunlight reached the patch and rainwater entered the pond. New leaves appeared. Ducks ate some leaves, and the naturalists found duck droppings near the patch. Later, several older leaves broke off and sank into the mud.

The naturalists placed 30 grams of dead pondweed in a vented mesh bag on the muddy bottom. The bag let water and tiny organisms pass through but held larger pieces. They weighed the pieces after five and ten days. The same bag type, starting mass, pond location, and weighing method were used each time.

The record showed that the dead pondweed pieces became smaller and lighter. After ten days, a thin coating of fungi covered some pieces. The naturalists also found tiny fragments mixed into the mud. Water moved through the mud during the observation. These observations did not show that matter vanished; they showed that the pieces changed and that some material moved into other parts of the cove.

The camp team used the observations to plan a matter model. Their model needed to include a plant, an animal, decomposers, and the nonliving environment. An arrow in the model meant that some matter could move from one part to another. Sunlight could be shown as energy entering the pondweed, but sunlight itself was not matter added to the plant.