Lichen based index to nitrogen air quality guide
The Lichen based index to nitrogen air quality guide is a modern update of this fieldwork classic.
- Uses a small number of readily-identified lichen species
- Concentrates on lichens growing on oak and birch, common and easily identified trees
- Ideal for small-scale scientific investigations
Lichens are excellent natural indicators because they react quickly to subtle changes in air quality. In the past, sulphur dioxide from coal burning and industry was the main pollutant, driving acid rain. Today, nitrogen compounds from intensive farming and vehicle exhausts have taken over as the leading threat.
While many lichens suffer or disappear due to pollution, some tolerate or even thrive in these conditions. This guide highlights which lichens withstand nitrogen pollution, and which signal clean, unpolluted air.
Students, amateur naturalists and community groups can easily monitor local lichen populations to track atmospheric nitrogen pollution. By comparing lichens on trunks with those on twigs, it is possible to spot changes in air quality over time. Even small-scale studies can uncover clear patterns about local pollution and broader environmental trends.
Field Studies Council worked with the UK Centre for Ecology and Hydrology, Natural History Museum and the University of Nottingham to produce this guide.
