Updates from the Field

Activities: Songnen Plain

Science: Wetlands as Filters

This week's field update introduces the wetlands of Northeast China and their importance to cranes and people in this region. Wetlands not only provide important habitat for cranes and many other animals, but they also help absorb excess water to lesson flooding and clean and filter water for both wildlife and people. This week's activity focuses on the role of wetlands as filters and can be done in the classroom using tap water (just add soil to the water for the experiment) or outdoors using water from a nearby river, lake or wetland. The activity was developed by Amy Fare, a teacher at Hawley Environmental School in Milwaukee, WI. Mrs. Fare led this activity (right) at the student environmental camp held at Xianghai Nature Reserve this summer.

Materials: plastic bottles (such as liter soda bottles or smaller beverage bottles), sand, rocks, coffee filters, and other items that can be easily found, such as grass, leaves, etc.

Procedure: Cut the plastic bottles for the experiment in half (depending on the age of your students, you may choose to do this ahead of time) - for this experiment you will use the top half of each bottle. Explain to your students that they will be layering different materials in the bottle to represent the layers of vegetation, sediment and rock in a natural wetland. Give each student or group of students the top half of a bottle and ask them to layer the coffee filter, sand, rock and other materials inside the container. Using the collected water samples (or simply using tap water with soil added), ask students to pour the water through their filter (the water should exit out of the top opening of the bottle) into a clear or light colored container. Students should observe that the water is cleaner as it filters through the materials in the bottle. After completing the experiment, review the role of wetlands as nature's natural water filter and the importance of wetlands in keeping our water clean.