The Dutch dunes are a unique area both on a national and a European level. But during the previous century the dunes underwent dramatic changes.

Decreasing dynamism

First of all, this had to do with protecting the coast against the sea. Around 1900, artificial dune rows were built on a large scale; first by private individuals, later on by Rijkswaterstaat (Dutch Directorate for Public Works and Water Management).

To fix the dunes, Staatsbosbeheer planted woodlands. Although these measures were effective, they also caused a decrease in dynamism.

Dune ageing

Wind and water could no longer affect the dunes. This caused the dunes to become overgrown. Older vegetation left less space for younger vegetation with mosses and small species of plant, insects and insect eating birds. Exceptional dune types in particular suffered from this development which is referred to as dune ageing.

Tourism

Ageing was also caused by changes in dune usage which started in the early 20th century. Up until then, farmers and other coastal inhabitants had ensured the rejuvenation of the dunes through turf cutting, mowing, burning and livestock grazing. However, they increasingly retreated from the dune areas. The tourism that replaced them had much less effect on the area.

Drinking water

A third factor which harmed the dunes from the close of the 19th century onwards, was the collection of groundwater for use as drinking water. To compensate for the water removed, river water was pumped into the dunes, however this was far too nutrient rich. This created far too much vegetation which led to further ageing. Furthermore, the dunes desiccated anyway. Since the 1980s, environmentally friendly methods of water collection have been employed. However, the dunes have not yet fully recovered.

Acid rain

Finally, acid rain also causes ageing. The precipitation of nitrogen promotes the strong growth of some plants at the expense of others.