Veranderingen in de korstmos-vegetatie van het Wekeromse Zand (II): een vergelijking tussen 1994 en 2004

In the previous review (period 1984-1994) the subject of discussion was a decrease of the quantity of lichens in the nature reserve of 190 ha inland sand-dune landscape in the Veluwe region of Gelderland, while the species diversity remained high. In 1992- 1993 management measures in this reserve, such as the cutting and removing of 35 ha pine-trees and sod-cutting, were implemented in order to regain an open inland sand-dune landscape. In 2003 it became apparent that too much erosion had harmed the lichen-steppe in the northern part, which had changed into a pioneer vegetation with the moss Polytrichum piliferum. In the southern part with fewer dynamics, the influence was visible of the aerial nitrogen deposition. For the reserve as a whole the lichen diversity remained high, but since 1994 the quantity has decreased even more.