Abstract
Eutrophication is the process of nutrient enrichment of an ecosystem. The chemicals most responsible for eutrophication are compounds of nitrogen and phosphorus.
The effect of nitrogen compounds in the air and their combination with phosphorus on epiphytic lichens is considered. It is universally acknowledged that with a rising concentration of nitrogen there is gradual decrease in the number of acidophytes and increase of nitrophytes.
In extreme cases, with increasing concentrations of nitrogen even the nitrophytes will be adversely impacted and eventually there will be a complete loss of a lichen cover. However a balanced supply of nitrogen and phosphorus compounds can lead to a higher growth of cyanolichens.
Good indicators of eutrophication include the lichens Physconia grisea, Phaeophyscia orbicularis and Xanthoria parietina.