A Pollution Intensity Map

Laying out a grid of multiple transects permits a more systematic sampling of an area, which can then generate a map with regions of lichen dominance displayed in zones. You might have your class draw a grid on a map of the area to be surveyed, and assign students to various squares. Irish studies assign 5 km (rural) and 1 km (urban) squares to students, ask them to log 10 mature trees within "their" squares, avoiding coniferous trees. If your class is near or in a city, try to include some of the the city center and some of the surrounding countryside.

The first steps of the procedure are the same as above.

Steps 1-6. Same as Transect Activity, but ruled as a grid.

Step 7. Record on your map's squares whether or not they are primarily:
• F3, in which all three forms of lichens are present
• F2, in which crustose and foliose are present
• F1, in which only crustose is present
• F0, in which no lichens are present

Step 8. Display the results; students should color their squares as follows:
• F3 blue
• F2 green
• F1 yellow
• F0 red

Step 9. Evaluating your data. The extent of your local pollution should be clear from the arrangement of colors.
Zone 1 (F0-red) Inner zone, the "lichen desert"
Zone 2 (F1 yellow and F2 green)Transitional, intermediate zone
1. (F1-yellow) Only crustose present
2. (F2-green) Foliose present, as well as crustose
Zone 3 (F3-blue) Outer zone Fruticose present, as well as crustose and foliose.

Back to Classroom Activities
Back to Lichens Index

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