PHOTO: PIXABAY
They may seem insignificant, those small patches on trees and stones, but lichens are fascinating symbioses that reveal a surprising amount about air quality. In this fieldwork assignment from Veldwerk in de stad, pupils in years 10 and 11 investigate the distribution of lichens in their local environment. By comparing two locations, identifying species and analysing the relationship with nitrogen deposition, they bring ecological concepts such as symbiosis, biodiversity and the nitrogen cycle to life. Theory becomes practice, with real observations and real data. The assignment is fully worked out, including practical tools such as identification aids and an assessment rubric, and can be carried out flexibly within three to five lesson hours. The project is also well suited to extension as an extended research project. The teacher and pupil guides are available at tinyurl.com/bdhatdsz and tinyurl.com/4538rz7j. (Milena Vlot)