Description
Intermediate – Easy to perform; requires some basic training in microbiology.
For a class of 30. Lichens are extremely sensitive to air pollution. Their decreasing numbers in a particular location are an indication of increasing air pollution. Students stain a lichen sample and then subject it to various cation solutions. The speed with which the dye is leached out of the lichen correlates with the speed at which these cations from polluted air are taken up by lichen in nature.
The exercise can be completed in 2 class periods. A paper punch is needed but not included. With teacher instructions.