In this activity, students investigate microbial presence in soil by building a habitat suitable for their growth.
Known as Winogradsky columns, mud, newspaper and eggs create a variety of habitats that promote the growth of soil bacteria and algae. With time, sulfur and oxygen gradients form and a diversity of microorganisms grow in response to these conditions, often forming distinctive colour bands.
By the end of this activity, students should be able to:
- demonstrate that the soil is home to many microorganisms.
- explain that microbes grow in response to different needs such as light, oxygen, no oxygen and various energy sources.
Download the Word file for:
- introduction/background notes
- what you need
- what to do
- discussion questions
- student handout.
