Yesterday, Nick from King County Solid Waste joined us as a guest speaker. Nick brought biospheres, fully-enclosed glass spheres filled with water (and a little air). In the water were tiny shrimp, bacteria, algae, rocks, coral, and the occasional shell. Nick explained that the organisms in the biosphere have been alive for a few years now, and the biotic and abiotic factors present within the sphere, along with sunlight, are all the factors needed to keep the organisms thriving. He explained how matter circulates within the biosphere, and then asked students to contrast a biosphere with our planet. Students then participated in a sorting activity where they learned which items can be reused, recycled, composted, thrown away, or perhaps should not be purchased in the first place. The biospheres provided an excellent way to visualize the concept that the amount of matter in an ecosystem does not change, although the form that matter takes does change.
Biospheres, or ecospheres, are available for purchase, including online through Amazon.com.