About half of the Netherlands is covered by an acid eolian sand layer
deposited in the early quartenery. Lots of lichen rich inland dunes
can be found on these acid soils when dominated by Corynephorus canescens
grasslands. These lichen vegetations seem
to be quite stable during the last 40 years, but deposition of nitrogen caused a decline. Not all species have been
affected by this form of pollution, but species that (almost)
disappeared since 1960 are Cl. cornuta, Cl.
phyllophora, Cl. squamosa, Cetraria
islandica and Stereocaulon saxatile.