The Amsterdam Dunes are located on the Dutch mainland coast south of Zandvoort. In this unique 35 km2 dune reserve, Waternet purifies 2/3 of the drinking water for the city of Amsterdam. Water treatment, nature and recreation are balanced and co-exist side by side. Waternet started the LIFE+ project in 2011 to restore 350 hectare of dune habitat.
The Amsterdam Dunes are owned by the Municipality of Amsterdam. Since 1850 the area of the habitat types deteriorated notably in size and quality from desiccation due to water extraction, from air pollution and acidification and eutrophication (nitrogen deposition). This has led to widespread grass and shrub encroachment and accumulation of nitrogen-rich organic matter in the topsoil.
In recent decades this negative environmental impact decreased: the method of water production in the area has changed and the groundwater of the area is rising again, the nitrogen deposition has been reduced by national and international (generic) measures in industry and transport. To reach the N2000 goals and to stimulate nature recovery, it is necessary that the effects of desiccation and eutrophication be addressed by removing the nitrogen-rich top layer of soil and other nature management measures. Special attention has to be addressed to the recent expansion of the invasive alien species Prunus serotina (black cherry).
The aim of the project is rehabilitation and improvement of 350 hectare of characteristic and priority habitat types in the Amsterdam Dunes, which are part of the Natura 2000 area 'Kennemerland Zuid.' More specifically the goals are:
expansion and quality improvement for the priority habitat type 'Fixed coastal dunes with herbaceous vegetation' (H 2130, Grey Dunes);
expansion and quality improvement of the habitat type 'Dunes with Hippophae rhamnoides' (H2160, thickets of sea buckthorn);
expansion and quality improvement of the habitat type 'Humid dune slacks' (H2190); this will include habitat designed for the close whorl snail (H1014) and the mottled white-faced darter (H1042).
The implementation of the project will focus on the removal of the disturbed vegetation and soil organic matter and consequences at the start of recovery management. Measures will also be taken to avoid the risk of recurrence of the invasive species Prunus serotina (black cherry). The measures consist of the following activities:
mowing of vegetation and removal of organic material in the dune slacks;
removing the organic top soil layer in dune slacks and dune grassland and turfing;
excavation of old blow-outs;
lifting and removal of shrubs and trees, in particular the invasive exotic species of Prunus serotina and a Pinus nigra stand;
turfing former thickets of Prunus serotina, including the seed bank (following activity 4);
rehabilitation of ponds by the removal of bank vegetation and dredging.