(Courtesy of Tom Hanson, University of Delaware)
In this activity, students mix mud, water, a carbon source, and a sulfur source together in a clear bottle. The mud and water contain many different types of bacteria, while the carbon and sulfur serve as "food" for bacteria to grow. After the bottles are left in the sun for several weeks, distinct layers of bacterial colonies in become visible. Each colony fills a specific niche within the bottle ecosystem, generally following each bacteria type's
Winogradsky Lesson: The "General Biology of the Column" section gives a great in-depth explanation of what each type of bacteria does (probably too advanced for students but will help teachers understand these processes in depth).
Winogradsky Website from the University of Delaware
K-12 Unifying Concepts and Processes
9-12 A Science as Inquiry
9-12 B Physical Science
9-12 C Life Science